Crown Castle
Annual Report 2017

Plain-text annual report

UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549___________________________________FORM 10-K __________________________xANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934For the fiscal year ended December 31, 2017or oTRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934For the transition period from to Commission File Number 001-16441 __________________________CROWN CASTLE INTERNATIONAL CORP.(Exact name of registrant as specified in its charter) __________________________ Delaware 76-0470458(State or other jurisdictionof incorporation or organization) (I.R.S. EmployerIdentification No.) 1220 Augusta Drive, Suite 600, Houston Texas 77057-2261(Address of principal executive offices) (Zip Code)(713) 570-3000(Registrant's telephone number, including area code) Securities Registered Pursuant toSection 12(b) of the Act Name of Each Exchangeon Which RegisteredCommon Stock, $0.01 par value New York Stock Exchange6.875% Mandatory Convertible Preferred Stock, Series A, $0.01 par value New York Stock ExchangeSecurities Registered Pursuant to Section 12(g) of the Act: NONE. ______________________________________Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes x No oIndicated by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes o No xIndicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes x No oIndicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted andposted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit andpost such files). Yes x No oIndicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant'sknowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. o Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a small reporting company or an emerging growthcompany. See definitions of a "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in rule 12b-2 of the Exchange Act. Large accelerated filer x Accelerated filer o Non-accelerated filer o (Do not check if a smaller reporting company) Smaller reporting company o Emerging growthcompany oIf an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financialaccounting standards provided pursuant to Section 13(a) of the Exchange Act oIndicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes o No xThe aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant was approximately $36.5 billion as of June 30, 2017, the lastbusiness day of the registrant's most recently completed second fiscal quarter, based on the New York Stock Exchange closing price on that day of $100.18 per share.Applicable Only to Corporate RegistrantsAs of February 21, 2018, there were 406,906,992 shares of common stock outstanding.Documents Incorporated by ReferenceThe information required to be furnished pursuant to Part III of this Form 10-K will be set forth in, and incorporated by reference from, the registrant's definitive proxystatement for the annual meeting of stockholders ("2018 Proxy Statement"), which will be filed with the Securities and Exchange Commission not later than 120 days after the end ofthe fiscal year ended December 31, 2017.CROWN CASTLE INTERNATIONAL CORP.TABLE OF CONTENTS Page PART I Item 1. Business 1Item 1A. Risk Factors 9Item 1B. Unresolved Staff Comments 20Item 2. Properties 20Item 3. Legal Proceedings 20Item 4. Mine Safety Disclosures 20 PART II Item 5. Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities 21Item 6. Selected Financial Data 24Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations 26Item 7A. Quantitative and Qualitative Disclosures About Market Risk 45Item 8. Financial Statements and Supplementary Data 48Item 9. Changes in and Disagreements With Accountants on Accounting and Financial Disclosure 91Item 9A. Controls and Procedures 91Item 9B. Other Information 92 PART III Item 10. Directors and Executive Officers of the Registrant 92Item 11. Executive Compensation 92Item 12. Security Ownership of Certain Beneficial Owners and Management 92Item 13. Certain Relationships and Related Transactions 92Item 14. Principal Accounting Fees and Services 92 PART IV Item 15. Exhibits, Financial Statement Schedules 93Item 16. Form 10-K Summary 101 Signatures 104Cautionary Language Regarding Forward-Looking StatementsThis Annual Report on Form 10-K contains forward-looking statements that are based on our management's expectations as of the filing date of thisreport with the Securities and Exchange Commission ("SEC"). Statements that are not historical facts are hereby identified as forward-looking statements. Inaddition, words such as "estimate," "anticipate," "project," "plan," "intend," "believe," "expect," "likely," "predicted," "positioned" and any variations of thesewords and similar expressions are intended to identify forward-looking statements. Such statements include plans, projections and estimates contained in"Item 1. Business," "Item 3. Legal Proceedings," "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations"("MD&A"), and "Item 7A. Quantitative and Qualitative Disclosures About Market Risk" herein. Such forward-looking statements include (1) expectationsregarding anticipated growth in the wireless industry, carriers' investments in their networks, tenant additions, customer consolidation or ownership changes,and demand for our communications infrastructure (as defined below), (2) expectations regarding non-renewals of tenant contracts, (3) availability andadequacy of cash flows and liquidity for, or plans regarding, future discretionary investments, including capital expenditures, (4) potential benefits of ourdiscretionary investments, including acquisitions, (5) anticipated growth in our financial results, including future revenues, Adjusted EBITDA, segment siterental gross margin, segment network services and other gross margin, segment operating profit and operating cash flows, (6) expectations regarding ourcapital structure and the credit markets, our availability and cost of capital, and our ability to service our debt and comply with debt covenants and the plansfor and the benefits of any future refinancings, (7) expectations related to remaining qualified as a real estate investment trust ("REIT"), and the advantages,benefits or impact of, or opportunities created by, our REIT status and the impact of the Tax Cuts and Jobs Act ("Tax Reform Act"), (8) the realization andutilization ofour net operating loss carryforwards ("NOLs"), and (9) our dividend policy, and the timing, amount, growth or tax characterization of any dividends.Such forward-looking statements should, therefore, be considered in light of various risks, uncertainties and assumptions, including prevailing marketconditions, risk factors described under "Item 1A. Risk Factors" herein and other factors. Should one or more of these risks or uncertainties materialize, orshould underlying assumptions prove incorrect, actual results may vary materially from those expected.InterpretationAs used herein, the term "including," and any variation thereof, means "including without limitation." The use of the word "or" herein is not exclusive.Unless this Form 10-K indicates otherwise or the context otherwise requires, the terms, "we," "our," "our company," "the company" or "us" as used in this Form10-K refer to Crown Castle International Corp. and its predecessor (organized in 1995), as applicable, each a Delaware corporation (together, "CCIC"), andtheir subsidiaries. Additionally, unless the context suggests otherwise, references to "U.S." are to the United States of America and Puerto Rico, collectively.PART IItem 1. BusinessOverviewWe own, operate and lease shared communications infrastructure that is geographically dispersed throughout the U.S., including (1) approximately40,000 towers and other structures, such as rooftops (collectively, "towers"), and (2) approximately 60,000 route miles of fiber primarily supporting small cellnetworks ("small cells") and fiber solutions. Our towers, fiber and small cells assets are collectively referred to herein as "communications infrastructure," andour customers on our communications infrastructure are referred to herein as "tenants." Our core business is providing access, including space or capacity, toour shared communications infrastructure via long-term contracts in various forms, including lease, license, sublease and service agreements (collectively,"contracts"). We seek to increase our site rental revenues by adding more tenants on our shared communications infrastructure, which we expect to result insignificant incremental cash flows due to our low incremental operating costs.Below is certain information concerning our business:•Over the last two decades, we have assembled a leading portfolio of towers predominately through acquisitions from large wireless carriers or theirpredecessors. More recently, through both acquisitions (see note 4 to our consolidated financial statements) and new construction of small cellsand fiber, we have extended our communications infrastructure presence by investing significantly in our Fiber segment. Through our productofferings of towers and small cells, we seek to provide a comprehensive solution to enable our wireless customers to expand coverage and capacityfor wireless networks. Furthermore, within our Fiber segment, we are able to generate cash flow growth and stockholder return by deploying ourfiber for both small cells' and fiber solutions' customers.•As a result of our 2017 Acquisitions of fiber assets as further described in note 4 to our consolidated financial statements, we changed the name ofour "Small Cells" operating segment to "Fiber." We changed the name of this segment to reflect our strategy of utilizing the same fiber assets toprovide both small cells and fiber solutions to our customers. The name change did not impact the composition or the previously-reportedoperating results of the Fiber segment. As such, our operating segments are now referred to as "Towers" and "Fiber." Our Towers segment and Fibersegment accounted for 79% and 21% of our 2017 site rental revenues, respectively. See note 16 to our consolidated financial statements.•Below is certain information regarding our Towers segment:◦Approximately 56% and 71% of our towers are located in the 50 and 100 largest U.S. basic trading areas ("BTAs"), respectively. Ourtowers have a significant presence in each of the top 100 BTAs.◦We derive in excess of one-third of our Towers site rental gross margin on land and other property interests (collectively, "land") that weown, including fee interests and perpetual easements, and we derive approximately two-thirds of our Towers site rental gross margin fromland that we lease, sublease, manage or license.◦The contracts for the land under our towers have an average remaining life in excess of 30 years (including renewal terms at our option),weighted based on Towers site rental gross margin.•Below is certain information regarding our Fiber segment:◦The majority of our small cells and fiber are located in major metropolitan areas, including a presence within every major U.S. market.◦The vast majority of our fiber assets are located on public rights-of-way.•We operate as a REIT for U.S. federal income tax purposes. See "Item 1. Business—2017 Industry Highlights and Company Developments—REITStatus" and note 11 to our consolidated financial statements.Certain information concerning our customers and site rental contracts is as follows:•Our customers include AT&T, T-Mobile, Verizon Wireless and Sprint, which collectively accounted for 83% of our 2017 site rental revenues.•Site rental revenues represented 84% of our 2017 consolidated net revenues.•The vast majority of our site rental revenues are of a recurring nature, and typically in excess of 90% have been contracted for in a prior year.•Our site rental revenues derived from wireless customers typically result from long-term contracts with (1) initial terms of five to 15 years,(2) multiple renewal periods at the option of the customer of five to ten years each, (3) limited termination rights for our customers, and (4)contractual escalations of the rental price and, in some cases, an additional upfront payment.1•Our site rental revenues derived from our fiber solutions business (including from organizations with high-bandwidth and multi-locationdemands), typically result from contracts with (1) initial terms that generally vary between three to 20 years and (2) a fixed monthly recurring feeand, in some cases, an additional upfront payment.•Exclusive of renewals at the customers' option, our customer contracts have a weighted-average remaining life of approximately five years andrepresent $22 billion of expected future cash inflows.As part of our effort to provide comprehensive communications infrastructure solutions, we also offer certain network services primarily relating to ourtowers and small cells, predominately consisting of (1) site development services relating to existing or new tenant equipment installations, including: siteacquisition, architectural and engineering, or zoning and permitting (collectively, "site development services") and (2) tenant equipment installation orsubsequent augmentations (collectively, "installation services"). The large majority of our network services and other revenues relate to our Towers segment.StrategyAs a leading provider of shared communications infrastructure in the U.S., our strategy is to create long-term stockholder value via a combination of (1)growing cash flows generated from our portfolio of communications infrastructure, (2) returning a meaningful portion of our cash provided by operatingactivities to our stockholders in the form of dividends and (3) investing capital efficiently to grow cash flows and long-term dividends per share. Our U.S.focused strategy is based, in part, on our belief that the U.S. is the most attractive market for shared communications infrastructure investment with thegreatest long-term growth potential. We measure our efforts to create "long-term stockholder value" by the combined payment of dividends to stockholdersand growth in our per share results. The key elements of our strategy are to:•Grow cash flows from our communications infrastructure. We seek to maximize our site rental cash flows by working with our customers toprovide them quick access to our communications infrastructure and entering into associated long-term contracts. Tenant additions ormodifications of existing customer equipment (collectively, "tenant additions") enable our customers to expand coverage and capacity in order tomeet increasing demand for data, while generating high incremental returns for our business. We believe our product offerings of towers and smallcells provide a comprehensive solution to our wireless customers' growing network needs through our shared communications infrastructuremodel, which is an efficient and cost-effective way to serve our customers. Additionally, we believe our ability to share our fiber assets acrossmultiple customers to deploy both small cells and offer fiber solutions allows us to generate cash flows and increase stockholder return. We alsobelieve that there will be considerable future demand for our communications infrastructure based on the location of our assets and the rapidgrowth in demand for data.•Return cash provided by operating activities to stockholders in the form of dividends. We believe that distributing a meaningful portion of ourcash provided by operating activities appropriately provides stockholders with increased certainty for a portion of expected long-term stockholdervalue while still retaining sufficient flexibility to invest in our business and deliver growth. We believe this decision reflects the translation of thehigh-quality, long-term contractual cash flows of our business into stable capital returns to stockholders.•Invest capital efficiently to grow cash flows and long-term dividends per share. We seek to invest our available capital, including the net cashprovided by our operating activities and external financing sources, in a manner that will increase long-term stockholder value on a risk-adjustedbasis. Our historical investments have included the following (in no particular order):◦acquisitions or construction of towers, fiber and small cells;◦acquisitions of land interests under towers;◦improvements and structural enhancements to our existing communications infrastructure◦purchases of shares of our common stock from time to time; and◦purchases, repayments or redemptions of our debt.Our strategy to create long-term stockholder value is based on our belief that additional demand for our communications infrastructure will be createdby the expected continued growth in the demand for data. We believe that such demand for our communications infrastructure will continue, will result ingrowth of our cash flows due to tenant additions on our existing communications infrastructure, and will create other growth opportunities for us, such asdemand for new communications infrastructure.2Company Developments, REIT Status and Industry UpdatesCompany Developments. See "Item 1. Business—Overview," "Item 1. Business—The Company," "Item 7. MD&A" and our consolidated financialstatements for a discussion of certain recent developments, activities, and results, including (1) the increase in our quarterly common stock dividend, (2) ourrecent debt and equity financing activities, and (3) our January 2017 acquisition of FPL FiberNet Holdings, LLC and certain other subsidiaries of NextEraEnergy, Inc. ("FiberNet Acquisition"), our June 2017 acquisition of Wilcon Holdings LLC ("Wilcon Acquisition") and our November 2017 acquisition ofLTS Group Holdings LLC ("Lightower Acquisition") (collectively, "2017 Acquisitions").REIT Status. We commenced operating as a REIT for U.S. federal income tax purposes effective January 1, 2014. As a REIT, we are generally entitled toa deduction for dividends that we pay and therefore are not subject to U.S. federal corporate income tax on our net taxable income that is currently distributedto our stockholders. We may also be subject to certain federal, state, local, and foreign taxes on our income or assets, including (1) alternative minimum taxes(repealed effective January 1, 2018), (2) taxes on any undistributed income, (3) taxes related to our taxable REIT subsidiaries ("TRSs"), (4) franchise taxes, (5)property taxes and (6) transfer taxes. In addition, we could, in certain circumstances, be required to pay an excise or penalty tax, which could be significant inamount, in order to utilize one or more relief provisions under the Internal Revenue Code of 1986, as amended ("Code"), to maintain qualification fortaxation as a REIT.The recently-enacted Tax Reform Act makes substantial changes to the Code. Among the many changes impacting corporations are a significantreduction in the corporate income tax rate, repeal of the corporate alternative minimum tax for years beginning in 2018 and limitations on the deductibilityof interest expense. In addition, under the Tax Reform Act, qualified REIT dividends (within the meaning of Section 199A(e)(3) of the Code) constitute a partof a non-corporate taxpayer's "qualified business income amount" and thus our non-corporate U.S. stockholders may be eligible to take a qualified businessincome deduction in an amount equal to 20% of such dividends received from us. Without further legislative action, the 20% deduction applicable toqualified REIT dividends will expire on January 1, 2026. We do not expect the Tax Reform Act to materially impact us.The vast majority of our assets and revenues are in the REIT, including a substantial amount of our assets and revenues from our 2017 Acquisitions. Seenotes 4 and 11 to our consolidated financial statements. Additionally, we have included in TRSs certain other assets and operations. Those TRS assets andoperations will continue to be subject, as applicable, to federal and state corporate income taxes or to foreign taxes in the jurisdictions in which such assetsand operations are located.Our foreign assets and operations (including our tower operations in Puerto Rico) most likely will be subject to foreign income taxes in the jurisdictionsin which such assets and operations are located, regardless of whether they are included in a TRS.To remain qualified and be taxed as a REIT, we will generally be required to annually distribute to our stockholders at least 90% of our REIT taxableincome, after the utilization of our NOLs, (determined without regard to the dividends paid deduction and excluding net capital gain) (see notes 2 and 11 toour consolidated financial statements). Our quarterly common stock dividend will delay the utilization of our NOLs and may cause certain of the NOLs toexpire without utilization.Industry Update. During 2017, consumer demand for data continued to grow due to increases in data consumption and increased penetration ofbandwidth-intensive devices. This increase in data consumption is driven by growth in factors such as (1) mobile entertainment (such as mobile video,mobile applications, and social networking), (2) mobile internet usage (such as email and web browsing), (3) machine-to-machine applications or the"Internet of Things" (such as smart city technologies), and (4) the adoption of other bandwidth-intensive applications (such as cloud services and videocommunications). As a result, consumer wireless devices are trending toward bandwidth-intensive devices, including smartphones, laptops, tablets and otheremerging devices.We expect the following anticipated factors to contribute to potential demand for our communications infrastructure:•Consumers' growing wireless data consumption likely resulting in major wireless carriers continuing to upgrade and enhance their networks,including through the use of both towers and small cells, in an effort to improve network quality and capacity and customer retention or satisfaction;•Prior and future potential spectrum auctioned, licensed or made available by the Federal Communications Commission ("FCC") enabling additionalwireless carrier network development (such as FirstNet);•Next generation technologies and new uses for wireless communications may potentially result in new entrants or increased demand in the wirelessindustry, which may include companies involved in the continued evolution and deployment of the Internet of Things (such as connected cars,smart cities and virtual reality); and•The continued adoption of bandwidth-intensive applications could result in demand for high-capacity, multi-location, fiber-based networksolutions.3The CompanyVirtually all of our operations are located in the U.S. Our operating segments consist of Towers and Fiber. For more information about our operatingsegments, see "Item 7. MD&A—General Overview" and note 16 to our consolidated financial statements. Our core business is providing access, includingspace or capacity, to our shared communications infrastructure in the U.S. We believe our communications infrastructure is integral to our customers'networks and organizations. See "Item 1. Business—Strategy."Towers Segment. We believe towers are the most efficient and cost-effective solution for providing coverage and capacity for wireless carrier networkdeployments. We acquired ownership interests or exclusive rights to the majority of our towers directly or indirectly from the four largest wireless carriers (ortheir predecessors) through transactions consummated since 1999, including transactions with (1) AT&T in 2013 ("AT&T Acquisition"), (2) T-Mobile in2012 ("T-Mobile Acquisition"), (3) Global Signal Inc. in 2007 ("Global Signal Acquisition"), which had originally acquired the majority of its towers fromSprint, (4) companies now part of Verizon Wireless during 1999 and 2000 and (5) companies now part of AT&T during 1999 and 2000.We generally receive monthly rental payments from our Towers tenants, payable under long-term contracts. We generally negotiate initial contractterms of five to 15 years, with multiple renewal periods of five to 10 years each at the option of the tenant, and our contracts typically include fixedescalations (which generally exceed expected non-renewals, as discussed below) and, in some cases, an additional upfront payment. We continue to endeavorto negotiate with our existing customer base for longer contractual terms, which often contain fixed escalation rates.Our Towers tenant contracts have historically had a high renewal rate. With limited exceptions, our Towers tenant contracts may not be terminated priorto the end of their current term, and non-renewals have averaged approximately 2.5% of site rental revenues over the last five years (inclusive of non-renewalsas a result of the decommissioning of the former Leap Wireless, MetroPCS and Clearwire networks ("Acquired Networks")). In general, each tenant contractwhich is renewable will automatically renew at the end of its term unless the tenant provides prior notice of its intent not to renew. See note 15 to ourconsolidated financial statements for a tabular presentation of the minimum rental cash payments due to us by tenants pursuant to lease agreements withoutconsideration of tenant renewal options.The average monthly rental payment from a new tenant added to towers can vary based on (1) aggregate tenant volume, (2) the different regions in theU.S., or (3) the physical size, weight and shape of the antenna installation or related equipment. When possible, we seek to receive rental payment increases inconnection with contract amendments, pursuant to which our tenants add additional antennas or other equipment to our towers on which they already haveequipment pursuant to preexisting contracts.As of December 31, 2017, the average number of tenants (calculated as a unique license together with any related amendments thereto) per tower isapproximately 2.2. The following chart sets forth the number of existing tenants per tower as of December 31, 2017 (see "Item 7. MD&A—Accounting andReporting Matters—Critical Accounting Policies and Estimates" for a discussion of our impairment evaluation and our towers with no tenants).4Fiber Segment. Our Fiber segment includes both small cells and fiber solutions.•We offer certain fiber solutions to organizations with high-bandwidth and multi-location demands, such as enterprise, government, education,healthcare and wholesale customers. Our fiber solutions provide essential connectivity resources needed to create integrated networks and supportorganizations.•Our small cells offload data traffic from towers and bolster capacity in the areas of wireless networks where data demand is the greatest. Our smallcells are typically attached to public right-of-way infrastructure, including utility poles and street lights.Our fiber assets include those acquired from: (1) NextG Networks, Inc. in 2012 ("NextG Acquisition"), (2) Quanta Fiber Networks, Inc. in 2015 ("SunesysAcquisition") and (3) the 2017 Acquisitions.We generally receive monthly recurring payments from our Fiber tenants and, in some cases, receive upfront payments, payable pursuant to contracts.The amount of the monthly payments can also be influenced by the amount or cost of (1) construction for initial and subsequent tenants, (2) fiber strandrequirements and supply, (3) equipment at the site and (4) any upfront payment received.For both of our Towers and Fiber (primarily small cells) segments, we have existing master agreements with our largest customers, including AT&T, T-Mobile, Verizon Wireless and Sprint; such agreements provide certain terms (including economic terms) that govern our tenants' right to utilize ourcommunications infrastructure entered into by such carriers during the term of their master agreements.Approximately 55% of our direct site operating expenses consist of Towers ground lease expenses, and the remainder includes fiber access expenses(primarily leases of fiber assets and other access agreements to facilitate our communications infrastructure), property taxes, repairs and maintenance,employee compensation or related benefit costs, and utilities. Assuming current leasing activity levels, our cash operating expenses generally tend to escalateat approximately the rate of inflation. The addition of new tenants is achieved at a low incremental operating cost, delivering high incremental returns to ourbusiness. Our communications infrastructure portfolio requires minimal sustaining capital expenditures, including maintenance or other non-discretionarycapital expenditures, which are typically approximately 2% of net revenues. See note 15 to our consolidated financial statements for a tabular presentation ofthe rental cash payments owed by us to landlords pursuant to our contractual agreements.Network Services. As part of our effort to provide comprehensive communications infrastructure solutions, we also offer certain network servicesprimarily relating to our towers and small cells, predominately consisting of (1) site development services and (2) installation services. The large majority ofour network service and other revenues relate to our Towers segment. For 2017, approximately 65% of our network services and other revenues related toinstallation services, and the remainder predominately related to site development services. We seek to grow our network service and other revenues bycapitalizing on increased volumes that may result from carrier network upgrades, promoting site development services, expanding the scope of our services,and focusing on customer service and deployment speed. We have the capability and expertise to install, with the assistance of our network of subcontractors,equipment or antenna systems for our customers. We do not always provide the installation services or site development services for our customers on ourcommunications infrastructure as third parties also provide these services (see also "—Competition" below). These activities are typically non-recurring andhighly competitive, with a number of local competitors in most markets. Typically, our installation services are billed on a cost-plus profit basis and sitedevelopment services are billed on a fixed fee basis.Customers. Our Towers customers are primarily comprised of large wireless carriers that operate national networks.Our Fiber customers are generally large wireless carriers and organizations with high-bandwidth and multi-location demands, such as enterprise,government, education, healthcare and wholesale customers.5Our four largest customers are AT&T, T-Mobile, Verizon Wireless and Sprint. Collectively, these four customers accounted for 83% of our 2017 siterental revenues. Also see "Item 1A. Risk Factors" and note 16 to our consolidated financial statements. For 2017, our site rental revenues by customer were asfollows:Sales and Marketing. Our sales organization markets our towers, small cells and fiber with the objective of contracting access with customers to existingcommunications infrastructure or to new communications infrastructure prior to construction. We seek to become the critical partner and preferredindependent communications infrastructure provider for our customers and increase customer satisfaction relative to our peers by leveraging our (1) existingunique communications infrastructure footprint, (2) customer relationships, (3) process-centric approach, (4) technological tools and (5) constructioncapabilities and expertise.Our sales team is organized based on a variety of factors, including customer type (such as wireless carriers and organizations) and geography. A team ofnational account directors maintains our relationships with our largest customers. These directors work to develop communications infrastructure contracts,as well as to ensure that customers' communications infrastructure needs are efficiently translated into new contracts on our communications infrastructure.Sales personnel in our local offices develop and maintain relationships with our customers that are expanding their networks, entering new markets, seekingnew or additional communication infrastructure offerings, bringing new technologies to market or requiring maintenance or add-on business. In addition toour full-time sales or marketing staff, a number of senior-level employees spend a significant portion of their time on sales and marketing activities and callon existing or prospective customers.Competition. We face competition for site rental tenants from various sources, including (1) other independent communications infrastructure owners oroperators, including competitors that own, operate, or manage towers, rooftops, broadcast towers, utility poles, fiber (including non-traditional competitorssuch as cable providers) or small cells, or (2) new alternative deployment methods for communications infrastructure.Some of the larger companies with which we compete for Towers segment business opportunities include American Tower Corporation and SBACommunications Corporation. Our Fiber segment business competitors can vary significantly based on geography. Some of the larger companies with whichwe compete for Fiber segment business opportunities include other owners of fiber, as well as new entrants into small cells and fiber solutions. We believethat location, existing communications infrastructure footprint, deployment speed, quality of service, expertise, reputation, capacity and price have been andwill continue to be the most significant competitive factors affecting our businesses. See "Item 1A. Risk Factors."Competitors to our network services offering include site acquisition consultants, zoning consultants, real estate firms, right-of-way consulting firms,construction companies, tower owners or managers, radio frequency engineering consultants, telecommunications equipment vendors who can provideturnkey site development services through multiple subcontractors or our customers' internal staff. We believe that our customers base their decisions on theoutsourcing of network services on criteria such as a company's experience, record of accomplishment, reputation, price and time for completion of a project.EmployeesAt January 31, 2018, we employed approximately 4,500 people. We are not a party to any collective bargaining agreements. We have not experiencedany strikes or work stoppages, and management believes that our employee relations are satisfactory.6Regulatory and Environmental MattersWe are required to comply with a variety of federal, state, and local regulations and laws in the U.S., including FCC and Federal AviationAdministration ("FAA") regulations and those discussed under "—Environmental" below. To date, we have not incurred any material fines or penalties orexperienced any material adverse effects to our business as a result of any domestic or international regulations. The summary below is based on regulationscurrently in effect, and such regulations are subject to review or modification by the applicable governmental authority from time to time. If we fail to complywith applicable laws and regulations, we may be fined or even lose our rights to conduct some of our business.Federal Regulations. Both the FCC and the FAA regulate towers used for wireless communications, radio, or television broadcasting. Such regulationscontrol the siting, lighting, or marking of towers and may, depending on the characteristics of particular towers, require the registration of tower facilities withthe FCC and the issuance of determinations confirming no hazard to air traffic. Wireless communications devices operating on towers are separately regulatedand independently licensed based upon the particular frequency used. In addition, the FCC and the FAA have developed standards to consider proposals fornew or modified tower or antenna structures based upon the height or location, including proximity to airports. Proposals to construct or to modify existingtower or antenna structures above certain heights are reviewed by the FAA to ensure the structure will not present a hazard to aviation, which determinationmay be conditioned upon compliance with lighting or marking requirements. The FCC requires its licensees to operate communications devices only ontowers that comply with FAA rules and are registered with the FCC, if required by its regulations. Where tower lighting is required by FAA regulation, towerowners bear the responsibility of notifying the FAA of any tower lighting outage and ensuring the timely restoration of such outages. Failure to comply withthe applicable requirements may lead to civil penalties.Local Regulations. The U.S. Telecommunications Act of 1996 amended the Communications Act of 1934 to preserve state and local zoning authorities'jurisdiction over the siting of communications towers and small cells. The law, however, limits local zoning authority by prohibiting actions by localauthorities that discriminate between different service providers of wireless communications or ban altogether the provision of wireless communications.Additionally, the law prohibits state and local restrictions based on the environmental effects of radio frequency emissions to the extent the facilities complywith FCC regulations.Local regulations include city and other local ordinances (including subdivision and zoning ordinances), approvals for construction, modification andremoval of towers and small cells, and restrictive covenants imposed by community developers. These regulations vary greatly, but typically require us toobtain approval from local officials prior to tower construction. Local zoning authorities may render decisions that prevent the construction or modificationof towers or place conditions on such construction or modifications that are responsive to community residents' concerns regarding the height, visibility, orother characteristics of the towers. Over the last several years, there have been several developments related to FCC regulations and legislation that assist inexpediting and streamlining the deployment of wireless networks, including establishing timeframes for reviews by local and state governments.Notwithstanding such legislative and FCC actions, decisions of local zoning authorities may also adversely affect the timing or cost of communicationsinfrastructure construction or modification.Certain of our Fiber related subsidiaries hold authorizations to provide intrastate telecommunication services as competitive local exchange carriers("CLEC") in numerous states and to provide domestic interstate telecommunication services as authorized by the FCC. These Fiber subsidiaries are primarilyregulated by state public service commissions. CLEC status, in certain cases, helps promote access to public rights-of-way, which is beneficial to thedeployment of our small cells on a timely basis. Status as a CLEC often allows us to deploy our small cells in locations where zoning restrictions mightotherwise delay, restrict, or prevent building or expanding traditional wireless tower sites or traditional wireless rooftop sites. See "Item 1A. Risk Factors."Environmental. We are required to comply with a variety of federal, state, and local environmental laws and regulations protecting environmentalquality, including air and water quality and wildlife protection. To date, we have not incurred any material fines or penalties or experienced any materialadverse effects to our business as a result of any domestic or international environmental regulations or matters. See "Item 1A. Risk Factors."The construction of new towers and small cells or, in some cases, the modification of existing towers in the U.S. may be subject to environmental reviewunder the National Environmental Policy Act of 1969, as amended ("NEPA"), which requires federal agencies to evaluate the environmental impact of majorfederal actions. The FCC has promulgated regulations implementing NEPA, which require applicants to investigate the potential environmental impact of theproposed tower or small cells construction. Should the proposed tower or small cells construction present a significant environmental impact, the FCC mustprepare an environmental impact statement, subject to public comment. If the proposed construction or modification of a tower may have a significant impacton the environment, the FCC's approval of the construction or modification could be significantly delayed.Our operations are subject to federal, state, and local laws and regulations relating to the management, use, storage, disposal, emission, or remediationof, or exposure to, hazardous or non-hazardous substances, materials, or wastes. As an owner, lessee, or operator of real property, we are subject to certainenvironmental laws that impose strict, joint-and-several liability for the7cleanup of on-site or off-site contamination relating to existing or historical operations; or we could also be subject to personal injury or property damageclaims relating to such contamination. In general, our customer contracts prohibit our customers from using or storing any hazardous substances on ourcommunications infrastructure sites in violation of applicable environmental laws and require our customers to provide notice of certain environmentalconditions caused by them.As licensees and communications infrastructure owners, we are also subject to regulations and guidelines that impose a variety of operationalrequirements relating to radio frequency emissions. As employers, we are subject to Occupational Safety and Health Administration and similar guidelinesregarding employee protection from radio frequency exposure. The potential connection between radio frequency emissions and certain negative healtheffects, including some forms of cancer, has been the subject of substantial study by the scientific community in recent years.We have compliance programs and monitoring projects to help assure that we are in substantial compliance with applicable environmental laws andregulations. Nevertheless, there can be no assurance that the costs of compliance with existing or future environmental laws will not have a material adverseeffect on us.Other Regulations. We hold, through certain of our subsidiaries, licenses for common carrier microwave service, which are subject to additionalregulation by the FCC. We also hold a nationwide FCC license relating to the 1670-1675 MHz spectrum ("1670-1675 Spectrum"), which we have leased to athird party through 2023, subject to the lessee's option to purchase the 1670-1675 Spectrum.8Item 1A. Risk FactorsYou should carefully consider all of the risks described below, as well as the other information contained in this document, when evaluating yourinvestment in our securities.Risks Relating to Our BusinessOur business depends on the demand for our communications infrastructure, driven primarily by demand for data, and we may be adversely affected by anyslowdown in such demand. Additionally, a reduction in the amount or change in the mix of network investment by our customers may materially andadversely affect our business (including reducing demand for tenant additions or network services).Customer demand for our communications infrastructure depends on the demand for data. The willingness of our customers to utilize ourcommunications infrastructure, or renew or extend existing contracts on our communications infrastructure, is affected by numerous factors, including:•consumers' and organizations' demand for data;•availability or capacity of our communications infrastructure or associated land interests;•location of our communications infrastructure;•financial condition of our customers, including their profitability and availability or cost of capital;•willingness of our customers to maintain or increase their network investment or changes in their capital allocation strategy;•need for integrated networks and organizations;•availability and cost of spectrum for commercial use;•increased use of network sharing, roaming, joint development, or resale agreements by our customers;•mergers or consolidations by and among our customers;•changes in, or success of, our customers' business models;•governmental regulations and initiatives, including local or state restrictions on the proliferation of communications infrastructure;•cost of constructing communications infrastructure;•our market competition;•technological changes, including those (1) affecting the number or type of communications infrastructure needed to provide data to a givengeographic area or which may otherwise serve as substitute or alternative to our communications infrastructure or (2) resulting in the obsolescenceor decommissioning of certain existing wireless networks; and•our ability to efficiently satisfy our customers' service requirements.A slowdown in demand for data or our communications infrastructure may negatively impact our growth or otherwise have a material adverse effect onus. If our customers or potential customers are unable to raise adequate capital to fund their business plans, as a result of disruptions in the financial andcredit markets or otherwise, they may reduce their spending, which could adversely affect our anticipated growth or the demand for our communicationsinfrastructure or network services.The amount, timing, and mix of our customers' network investment is variable and can be significantly impacted by the various matters described inthese risk factors. Changes in customer network investment typically impact the demand for our communications infrastructure. As a result, changes incustomer plans such as delays in the implementation of new systems, new and emerging technologies (including small cells and fiber solutions), or plans toexpand coverage or capacity may reduce demand for our communications infrastructure. Furthermore, the industries in which our customers operate(particularly those in the wireless industry) could experience a slowdown or slowing growth rates as a result of numerous factors, including a reduction inconsumer demand (including demand for wireless connectivity) or general economic conditions. There can be no assurances that weakness or uncertainty inthe economic environment will not adversely impact our customers or their industries, which may materially and adversely affect our business, including byreducing demand for our communications infrastructure or network services. In addition, a slowdown may increase competition for site rental customers ornetwork services. Such an industry slowdown or a reduction in customer network investment may materially and adversely affect our business.9A substantial portion of our revenues is derived from a small number of customers, and the loss, consolidation or financial instability of any of suchcustomers may materially decrease revenues or reduce demand for our communications infrastructure and network services.Our four largest customers are AT&T, T-Mobile, Verizon Wireless and Sprint. Collectively, these four customers accounted for 83% of our 2017 siterental revenues. The loss of any one of our large customers as a result of consolidation, merger, bankruptcy, insolvency, network sharing, roaming, jointdevelopment, resale agreements by our customers or otherwise may result in (1) a material decrease in our revenues, (2) uncollectible account receivables, (3)an impairment of our deferred site rental receivables, communications infrastructure assets, intangible assets, or (4) other adverse effects to our business. Wecannot guarantee that contracts with our major customers will not be terminated or that these customers will renew their contracts with us. In addition to ourfour largest customers, we also derive a portion of our revenues and anticipated future growth from (1) fiber solutions customers and (2) new entrants offeringor contemplating offering wireless services. Such customers (including those dependent on government funding) may be smaller or have less financialresources than our four largest customers, may have business models which may not be successful, or may require additional capital. See also "Item 1.Business—The Company" and note 16 to our consolidated financial statements.Consolidation among our customers will likely result in duplicate or overlapping parts of networks, for example, where they are co-residents on a tower,which may result in the termination or non-renewal of tenant contracts and negatively impact revenues from our communications infrastructure. Due to thelong-term nature of tenant contracts, we expect that any termination of tenant contracts as a result of this potential consolidation would be spread overmultiple years. Such consolidation may result in a reduction in such customers' future network investment in the aggregate because their expansion plansmay be similar. Customer consolidation could decrease the demand for our communications infrastructure, which in turn may result in a reduction in ourrevenues or cash flows.See note 15 to our consolidated financial statements.The expansion or development of our business, including through acquisitions, increased product offerings or other strategic growth opportunities, maycause disruptions in our business, which may have an adverse effect on our business, operations or financial results. Additionally, we may fail to realize allof the anticipated benefits of the Lightower Acquisition, or those benefits may take longer to realize than expected.We seek to expand and develop our business, including through acquisitions, increased product offerings (such as small cells and fiber solutions), orother strategic growth opportunities. In the ordinary course of our business, we review, analyze and evaluate various potential transactions or other activitiesin which we may engage. Such transactions or activities could cause disruptions in, increase risk or otherwise negatively impact our business. Among otherthings, such transactions and activities may:•disrupt our business relationships with our customers, depending on the nature of or counterparty to such transactions and activities;•divert the time or attention of management away from other business operations, including as a result of post-transaction integration activities;•fail to achieve revenue or margin targets, operational synergies or other benefits contemplated;•increase operational risk or volatility in our business;•not result in the benefits management had expected to realize from such expansion and development activities, or those benefits may take longerto realize than expected;•impact our cost structure and result in the need to hire additional employees;•increase demands on current employees or result in current or prospective employees experiencing uncertainty about their future roles with us,which might adversely affect our ability to retain or attract key employees; or•result in the need for additional TRSs or contributions of certain assets to TRSs, which are subject to federal and state corporate income taxes.With respect to our recent Lightower Acquisition (see note 4 to our consolidated financial statements), we may encounter significant difficulties inintegrating Lightower's business. Our ability to realize the anticipated benefits of the Lightower Acquisition will depend, to a large extent, on our ability tointegrate the Lightower business into ours. The integration of an independent business into our business is a complex, costly and time-consuming process. Asa result, we will be required to devote significant management attention and resources to integrate Lightower's business practices and operations with ours,including a larger fiber solutions business than we currently manage. The integration process may disrupt the businesses and, if implemented ineffectively,would reduce the realization of the full expected benefits. The failure to meet the challenges involved in integrating Lightower's business and to realize theanticipated benefits of the transaction could cause an interruption of, or a loss of momentum in, the activities of our Company and could adversely affect ourresults of operations. In addition, we could encounter additional10transaction-related costs or other factors, which could delay our realization of the expected benefits of the Lightower Acquisition and negatively impact ourbusiness.Our Fiber segment has expanded rapidly, and the Fiber business model contains certain differences from our Towers business model, resulting in differentoperational risks. If we do not successfully operate our Fiber business model or identify or manage the related operational risks, such operations mayproduce results that are less than anticipated.In recent years, we have allocated a significant amount of capital to our Fiber business, which is a much less mature business for us than our Towersbusiness (which we have operated since 1994). Our Fiber segment represented 21% and 12% of our site rental revenues for the years ended December 31,2017 and 2016, respectively. The business model for our Fiber operations contains certain differences from our business model for our Towers operations,including certain differences relating to customer base, competition, contract terms (including requirements for service level agreements regarding networkperformance and maintenance), upfront capital requirements, landlord demographics, ownership of certain network assets, operational oversightrequirements, government regulations, growth rates and applicable laws.While our Fiber operations have certain risks that are similar to our Towers operations, they also have certain operational risks that are different from ourTowers business, including:•the use of public rights-of-way and franchise agreements;•use of poles and conduits owned solely by, or jointly with, third parties;•risks relating to overbuilding;•risks relating to the specific markets that we choose to operate in or plan to operate in;•construction management risks;•risks relating to wireless carriers building their own small cell networks, or customers utilizing their own or alternative fiber assets;•risk of failing to optimize the use of our finite supply of fiber strands;•damage to our assets and the need to maintain, repair, upgrade and periodically replace our assets;•the risk of failing to properly maintain or operate highly specialized hardware and software;•network data security risks;•the risk of new technologies that could enable customers to realize the same benefits with less utilization of our fiber;•potential damage to our overall reputation as a communications infrastructure provider; and•the use of competitive local exchange carrier status, which we refer to as "CLEC" status.In addition, the rate at which customers adopt or prioritize small cells and fiber solutions may be lower or slower than we anticipate or may cease toexist altogether. Our Fiber operations will also expose us to different safety or liability risks or hazards than our Towers business as a result of numerousfactors, including the location or nature of the assets involved. There may be risks and challenges associated with small cells and fiber solutions beingcomparatively new and emerging technologies and continuing to evolve, and there may be other risks related to small cells and fiber solutions of which weare not yet aware.Failure to timely and efficiently execute on our construction projects could adversely affect our business.Our construction projects, some of which are long-term and complex in nature, can be challenging to execute. The quality of our performance on suchconstruction projects depends in large part upon our ability to manage (1) the associated customer relationship and (2) the project itself by timely deployingand properly managing appropriate internal and external project resources. In connection with our construction projects, we generally bear the risk of costover-runs, labor availability and productivity, and contractor pricing and performance. Additionally, contracts with our customers for these projects typicallyspecify delivery dates, performance criteria and penalties for our failure to perform. Our failure to manage such customer relationships, project resources, andproject milestones in a timely and efficient manner could have a material adverse effect on our business.Our substantial level of indebtedness could adversely affect our ability to react to changes in our business, and the terms of our debt instruments and our6.875% Convertible Preferred Stock limit our ability to take a number of actions that our management might otherwise believe to be in our best interests.In addition, if we fail to comply with our covenants, our debt could be accelerated.We have a substantial amount of indebtedness (approximately $16.2 billion as of February 21, 2018). See "Item 7. MD&A—Liquidity and CapitalResources" for a tabular presentation of our contractual debt maturities. As a result of our substantial indebtedness:•we may be more vulnerable to general adverse economic or industry conditions;•we may find it more difficult to obtain additional financing to fund discretionary investments or other general corporate requirements or torefinance our existing indebtedness;11•we are or will be required to dedicate a substantial portion of our cash flows from operations to the payment of principal or interest on our debt,thereby reducing the available cash flows to fund other projects, including the discretionary investments discussed in "Item 1. Business" and "Item7. MD&A—Liquidity and Capital Resources";•we may have limited flexibility in planning for, or reacting to, changes in our business or in the industry;•we may have a competitive disadvantage relative to other companies in our industry with less debt;•we may be adversely impacted by changes in interest rates;•we may be adversely impacted by changes to credit ratings related to our debt instruments;•we may be required to issue equity securities or securities convertible into equity or sell some of our assets, possibly on unfavorable terms, in orderto meet payment obligations;•we may be limited in our ability to take advantage of strategic business opportunities, including communications infrastructure development ormergers and acquisitions; and•we could fail to remain qualified for taxation as a REIT as a result of limitations on our ability to declare and pay dividends to stockholders as aresult of restrictive covenants in our debt instruments or the terms of our 6.875% Mandatory Convertible Preferred Stock, Series A, par value $0.01per share ("6.875% Convertible Preferred Stock").Currently we have debt instruments in place that limit in certain circumstances our ability to incur additional indebtedness, pay dividends, create liens,sell assets, or engage in certain mergers and acquisitions, among other things. In addition, the credit agreement governing our senior unsecured credit facility("2016 Credit Facility") contains financial maintenance covenants. Our ability to comply with these covenants or to satisfy our debt obligations will dependon our future operating performance. If we violate the restrictions in our debt instruments or fail to comply with our financial maintenance covenants, we willbe in default under those instruments, which in some cases would cause the maturity of a substantial portion of our long-term indebtedness to be accelerated.Furthermore, if the limits on our ability to pay dividends prevent us from satisfying our REIT distribution requirements, we could fail to remain qualified fortaxation as a REIT. If these limits do not jeopardize our qualification for taxation as a REIT but nevertheless prevent us from distributing 100% of our REITtaxable income, we will be subject to federal and state corporate income taxes, and potentially a nondeductible excise tax, on our undistributed taxableincome. If our operating subsidiaries were to default on their debt, the trustee could seek to foreclose the collateral securing such debt, in which case we couldlose the communications infrastructure and the revenues associated with such communications infrastructure. See "Item 7. MD&A—Liquidity and CapitalResources—Debt Covenants" for a further discussion of our debt covenants.CCIC is a holding company that conducts all of its operations through its subsidiaries. Accordingly, CCIC's sources of cash to pay interest or principalon its outstanding indebtedness are distributions relating to its respective ownership interests in its subsidiaries from the net earnings and cash flowsgenerated by such subsidiaries or from proceeds of debt or equity offerings. Earnings and cash flows generated by CCIC's subsidiaries are first applied bysuch subsidiaries to conduct their operations, including servicing their respective debt obligations, after which any excess cash flows generally may be paidto such holding company, in the absence of any special conditions such as a continuing event of default. However, CCIC's subsidiaries are legally distinctfrom the holding company and, unless they guarantee such debt, have no obligation to pay amounts due on their debt or to make funds available to us forsuch payment.If we fail to pay scheduled dividends on our 6.875% Convertible Preferred Stock, in cash, common stock, or any combination of cash and commonstock, we will be prohibited from paying dividends on our common stock, which may jeopardize our status as a REIT.We have a substantial amount of indebtedness. In the event we do not repay or refinance such indebtedness, we could face substantial liquidity issues andmight be required to issue equity securities or securities convertible into equity securities, or sell some of our assets to meet our debt payment obligations.We have a substantial amount of indebtedness, which, upon final maturity, we will need to refinance or repay. See "Item 7. MD&A—Liquidity andCapital Resources" for a tabular presentation of our contractual debt maturities. There can be no assurances we will be able to refinance our indebtedness (1)on commercially reasonable terms, (2) on terms, including with respect to interest rates, as favorable as our current debt, or (3) at all.Economic conditions and the credit markets have historically experienced, and may continue to experience, periods of volatility, uncertainty, orweakness that could impact the availability or cost of debt financing, including any refinancing of the obligations described above or on our ability to drawthe full amount of our $3.5 billion senior unsecured revolving credit facility under our 2016 Credit Facility ("2016 Revolver"), that, as of February 21, 2018,has $3.0 billion of undrawn availability.If we are unable to repay or refinance our debt, we cannot guarantee that we will be able to generate enough cash flows from operations or that we willbe able to obtain enough capital to service our debt, fund our planned capital expenditures or pay future dividends. In such an event, we could facesubstantial liquidity issues and might be required to issue equity securities or securities convertible into equity securities, or sell some of our assets to meetour debt payment obligations. Failure to repay or refinance12indebtedness when required could result in a default under such indebtedness. If we incur additional indebtedness, any such indebtedness could exacerbatethe risks described above.Sales or issuances of a substantial number of shares of our common stock or securities convertible into shares of our common stock may adversely affectthe market price of our common stock.Future sales or issuances of common stock or other equity related securities may adversely affect the market price of our common stock, including anyshares of our common stock issued to finance capital expenditures, finance acquisitions or repay debt. Our business strategy contemplates access to externalfinancing to fund certain discretionary investments, which may include issuances of common stock or other equity related securities. We maintain an "at-the-market" stock offering program ("ATM Program") through which we may, from time to time, issue and sell shares of our common stock having an aggregategross sales price of up to $500.0 million to or through sales agents. As of February 21, 2018, we had approximately $150 million of gross sales of commonstock remaining under our ATM Program. From time to time, we may refresh or implement a new "at-the-market" stock offering program. See note 12 to ourconsolidated financial statements. As of February 21, 2018, we had approximately 407 million shares of common stock outstanding.We have reserved 11.2 million and 17.2 million shares of common stock, respectively, for issuance in connection with awards granted under our variousstock compensation plans and our 6.875% Convertible Preferred Stock, which will automatically convert into common stock on August 1, 2020. See "Item 7.MD&A—Liquidity and Capital Resources—Mandatory Convertible Preferred Stock." The dividends on our 6.875% Convertible Preferred Stock may also bepaid in cash or, subject to certain limitations, shares of common stock or any combination of cash and shares of common stock.Further, a small number of common stockholders own a significant percentage of our outstanding common stock. If any one of these commonstockholders, or any group of our common stockholders, sells a large quantity of shares of our common stock, or the public market perceives that existingcommon stockholders might sell a large quantity of shares of our common stock, the market price of our common stock may significantly decline.As a result of competition in our industry, we may find it more difficult to negotiate favorable rates on our new or renewing tenant contracts.Our growth is dependent on our entering into new tenant contracts (including amendments to contracts upon modification of an existing tower, fiber, orsmall cell installation), as well as renewing or renegotiating tenant contracts when existing tenant contracts terminate. Competition in our industry may makeit more difficult for us to attract new customers, maintain or increase our gross margins, or maintain or increase our market share. We face competition for siterental tenants and associated contractual rates from various sources, including (1) other independent communications infrastructure owners or operators,including those that own, operate, or manage towers, rooftops, broadcast towers, utility poles, fiber (including non-traditional competitors such as cableproviders) or small cells, or (2) new alternative deployment methods for communications infrastructure.Our Fiber operations may have different competitors than our Towers business, including other owners of fiber, as well as new entrants into small cellsand fiber solutions, some of which may have larger networks or greater financial resources than we have.New technologies may reduce demand for our communications infrastructure or negatively impact our revenues.Improvements in the efficiency, architecture, and design of wireless networks may reduce the demand for our communications infrastructure. Forexample, new technologies that may promote network sharing, joint development, wireless backhaul, or resale agreements by our customers, such as signalcombining technologies or network functions virtualization, may reduce the need for our communications infrastructure. In addition, other technologies,such as WiFi, Distributed Antenna Systems ("DAS"), femtocells, other small cells, or satellite (such as low earth orbiting) and mesh transmission systems may,in the future, serve as substitutes for, or alternatives to, leasing on communications infrastructure that might otherwise be anticipated or expected had suchtechnologies not existed. In addition, new technologies that enhance the range, efficiency, and capacity of wireless equipment could reduce demand for ourcommunications infrastructure. Any significant reduction in demand for our communications infrastructure resulting from the new technologies maynegatively impact our revenues or otherwise have a material adverse effect on us.If we fail to retain rights to our communications infrastructure, including the land interests under our towers and the right-of-way and other agreementsrelated to our small cells and fiber solutions, our business may be adversely affected.The property interests, on which our communications infrastructure resides, including the land interests under our towers, consist of leasehold and sub-leasehold interests, fee interests, easements, licenses, and rights-of-way. A loss of these interests may interfere with our ability to conduct our business orgenerate revenues. For various reasons, we may not always have the ability13to access, analyze, or verify all information regarding titles or other issues prior to acquiring communications infrastructure. Further, we may not be able torenew ground leases on commercially viable terms. Our ability to retain rights to the land interests on which our towers reside depends on our ability topurchase such land, including fee interests and perpetual easements, or renegotiate or extend the terms of the leases relating to such land. Approximately 10%of our Towers site rental gross margin for the year ended December 31, 2017 was derived from towers where the leases for the interests under such towers hadfinal expiration dates of less than ten years. If we are unable to retain rights to the property interests on which our communications infrastructure resides, ourbusiness may be adversely affected.As of December 31, 2017, approximately 53% of our towers were leased or subleased or operated and managed under master leases, subleases, or otheragreements with AT&T, Sprint, and T-Mobile. We have the option to purchase these towers at the end of their respective lease terms. We have no obligationto exercise such purchase options. We may not have the required available capital to exercise our right to purchase some or all of these towers at the timethese options are exercisable. Even if we do have available capital, we may choose not to exercise our right to purchase these towers or some or all of the T-Mobile or AT&T towers for business or other reasons. In the event that we do not exercise these purchase rights, or are otherwise unable to acquire an interestthat would allow us to continue to operate these towers after the applicable period, we will lose the cash flows derived from such towers, which may have amaterial adverse effect on our business. In the event that we decide to exercise these purchase rights, the benefits of the acquisition of these towers may notexceed the costs, which could adversely affect our business. Additional information concerning these towers and the applicable purchase options as ofDecember 31, 2017 is as follows:•Approximately 22% of our towers are leased or subleased or operated and managed under a master prepaid lease or other related agreements withAT&T for a weighted-average initial term of approximately 28 years, weighted on site rental gross margin. We have the option to purchase theleased and subleased towers from AT&T at the end of the respective lease or sublease terms for aggregate option payments of approximately $4.2billion, which payments, if exercised, would be due between 2032 and 2048.•Approximately 16% of our towers are leased or subleased or operated and managed for an initial period of 32 years (through May 2037) undermaster leases, subleases or other agreements with Sprint. We have the option to purchase in 2037 all (but not less than all) of the leased andsubleased Sprint towers from Sprint for approximately $2.3 billion.•Approximately 15% of our towers are leased or subleased or operated and managed under a master prepaid lease or other related agreements withT-Mobile for a weighted-average initial term of approximately 28 years, weighted on site rental gross margin. We have the option to purchase theleased and subleased towers from T-Mobile at the end of the respective lease or sublease terms for aggregate option payments of approximately$2.0 billion, which payments, if exercised, would be due between 2035 and 2049. In addition, through the T-Mobile Acquisition, there areanother approximately 1% of our towers subject to a lease and sublease or other related arrangements with AT&T. We have the option to purchasethese towers that we do not otherwise already own at the end of their respective lease terms for aggregate option payments of up to approximately$405 million, which payments, if exercised, would be due between 2018 and 2032 (less than $10 million would be due before 2025).Under master lease or master prepaid lease arrangements we have with AT&T, Sprint and T-Mobile, certain of our subsidiaries lease or sublease, or areotherwise granted the right to manage and operate, towers from bankruptcy remote subsidiaries of such carriers. If one of these bankruptcy remote subsidiariesshould become a debtor in a bankruptcy proceeding and is permitted to reject the underlying ground lease, our subsidiaries could lose their interest in theapplicable sites. If our subsidiaries were to lose their interest in the applicable sites or if the applicable ground leases were to be terminated, we would lose thecash flow derived from the towers on those sites, which may have a material adverse effect on our business. We have similar bankruptcy risks with respect tosites that we operate under management agreements.For our small cells and fiber solutions, we must maintain rights-of-way, franchise, pole attachment, conduit use and other agreements to operate ourassets. For various reasons, we may not always have the ability to maintain these agreements or obtain future agreements to construct, maintain and operateour fiber assets. Access to rights-of-way depends in large part on our CLEC status, and we cannot be certain that jurisdictions will (1) recognize such CLECstatus or (2) not change their laws concerning CLEC access to rights-of-way. If a material portion of these agreements are terminated or are not renewed, wemight be forced to abandon our assets, which may adversely impact our business. In order to operate our assets, we must also maintain fiber agreements thatwe have with public and private entities. There is no assurance that we will be able to renew those agreements on favorable terms, or at all. If we are unable torenew those agreements on favorable terms, we may face increased costs or reduced revenues.14Additionally, in order to expand our communications infrastructure footprint to new locations, we often need to obtain new or additional rights-of-wayand other agreements. Our failure to obtain these agreements in a prompt and cost-effective manner may prevent us from expanding our footprint, which maybe necessary to meet our contractual obligations to our customers and could adversely impact our business.Our network services business has historically experienced significant volatility in demand, which reduces the predictability of our results.The operating results of our network services business for any particular period may vary significantly and should not necessarily be consideredindicative of longer-term results for this activity. Our network services business is generally driven by demand for our communications infrastructure and maybe adversely impacted by various factors, including:•competition;•the timing, mix and amount of customer network investments;•the rate and volume of customer deployment plans;•unforeseen delays or challenges relating to work performed;•economic weakness or uncertainty;•our market share; or•changes in the size, scope, or volume of work performed.New wireless technologies may not deploy or be adopted by customers as rapidly or in the manner projected.There can be no assurances that new wireless services or technologies will be introduced or deployed as rapidly or in the manner projected by thewireless carriers. In addition, demand or customer adoption rates for such new technologies may be lower or slower than anticipated for numerous reasons. Asa result, growth opportunities or demand for our communications infrastructure arising from such technologies may not be realized at the times or to theextent anticipated.If we fail to comply with laws or regulations which regulate our business and which may change at any time, we may be fined or even lose our right toconduct some of our business.A variety of federal, state, local, and foreign laws and regulations apply to our business, including those discussed in "Item 1. Business." Failure tocomply with applicable requirements may lead to civil or criminal penalties, require us to assume indemnification obligations or breach contractualprovisions. We cannot guarantee that existing or future laws or regulations, including federal, state, or local tax laws, will not adversely affect our business(including our REIT status), increase delays or result in additional costs. We also may incur additional costs as a result of liabilities under applicable laws andregulations, such as those governing environmental and safety matters. These factors may have a material adverse effect on us.If radio frequency emissions from wireless handsets or equipment on our communications infrastructure are demonstrated to cause negative health effects,potential future claims could adversely affect our operations, costs or revenues.The potential connection between radio frequency emissions and certain negative health effects, including some forms of cancer, has been the subjectof substantial study by the scientific community in recent years. We cannot guarantee that claims relating to radio frequency emissions will not arise in thefuture or that the results of such studies will not be adverse to us.Public perception of possible health risks associated with cellular or other wireless connectivity services may slow or diminish the growth of wirelesscompanies, which may in turn slow or diminish our growth. In particular, negative public perception of, and regulations regarding, these perceived healthrisks may slow or diminish the market acceptance of wireless services. If a connection between radio frequency emissions and possible negative health effectswere established, our operations, costs, or revenues may be materially and adversely affected. We currently do not maintain any significant insurance withrespect to these matters.Certain provisions of our restated certificate of incorporation ("Charter"), amended and restated by-laws ("by-laws") and operative agreements, anddomestic and international competition laws may make it more difficult for a third party to acquire control of us or for us to acquire control of a thirdparty, even if such a change in control would be beneficial to our stockholders.We have a number of anti-takeover devices in place that will hinder takeover attempts or may reduce the market value of our common stock. Our anti-takeover provisions include:•the authority of the board of directors to issue preferred stock without approval of the holders of our common stock;•advance notice requirements for director nominations or actions to be taken at annual meetings; and•a provision that the state courts or, in certain circumstances, the federal courts, in Delaware shall be the sole and exclusive forum for certainactions involving us, our directors, officers, employees and stockholders.15Our by-laws permit special meetings of the stockholders to be called only upon the request of our Chief Executive Officer or a majority of the board ofdirectors, and deny stockholders the ability to call such meetings. Such provisions, as well as the provisions of Section 203 of the Delaware GeneralCorporation Law, may impede a merger, consolidation, takeover, or other business combination or discourage a potential acquirer from making a tender offeror otherwise attempting to obtain control of us.In addition, domestic or international competition laws may prevent or discourage us from acquiring communications infrastructure in certaingeographical areas or impede a merger, consolidation, takeover, or other business combination or discourage a potential acquirer from making a tender offeror otherwise attempting to obtain control of us.We may be vulnerable to security breaches that could adversely affect our operations, business, and reputation.Despite existing security measures, certain of our communications infrastructure may be vulnerable to damage, disruptions, or shutdowns due tounauthorized access, computer viruses, cyber-attacks, and other security breaches. An attack attempt or security breach, such as a distributed denial of serviceattack, could potentially result in (1) interruption or cessation of certain of our services to our customers, (2) our inability to meet expected levels of serviceto our customers, or (3) data transmitted over our customers' networks being compromised. We cannot guarantee that our security measures will not becircumvented, resulting in customer network failures or interruptions that could impact our customers' network availability and have a material adverse effecton our business, financial condition, or operational results. We may be required to expend significant resources to protect against or recover from suchthreats. We maintain an insurance policy that includes coverage over cyber-attacks and other security breaches; however, there can be no assurances that suchcoverage will be adequate to cover exposure for such incidents. If an actual or perceived breach of our security occurs, the market perception of theeffectiveness of our security measures could be harmed, and we could lose customers. Further, the perpetrators of cyber-attacks are not restricted to particulargroups or persons. These attacks may be committed by our employees or external actors operating in any geography. In addition, our recent acquisitions,including the 2017 Acquisitions, may alter our potential exposure to the risks described above. We are currently evaluating such risks with respect to theseacquisitions. Any such events could result in legal claims or penalties, disruption in operations, misappropriation of sensitive data, damage to our reputation,negative market perception, or costly response measures, which could adversely affect our business.Risks Relating to Our REIT StatusFuture dividend payments to our stockholders will reduce the availability of our cash on hand available to fund future discretionary investments, and mayresult in a need to incur indebtedness or issue equity securities to fund growth opportunities. In such event, the then current economic, credit market orequity market conditions will impact the availability or cost of such financing, which may hinder our ability to grow our per share results of operations.During each of the first three quarters of 2017, we paid a quarterly common stock dividend of $0.95 per share, totaling approximately $1.1 billion. InOctober 2017, we increased our quarterly dividend, beginning in the fourth quarter of 2017, from an annual amount of $3.80 per share to an annual amountof $4.20 per share. As such, we declared a quarterly dividend of $1.05 per share in October 2017, which represented an increase of 11% from the quarterlydividend declared during each of the first three quarters of 2017. We currently expect such dividends to result in aggregate annual cash payments of at least$1.7 billion during the next 12 months. Over time, we expect to increase our dividend per share generally commensurate with our realized growth in cashflows. Any future dividends are subject to the approval of our board of directors. See notes 12 and 19 to our consolidated financial statements.We operate as a REIT for U.S. federal income tax purposes. To remain qualified and be taxed as a REIT, we will generally be required to annuallydistribute at least 90% of our REIT taxable income (determined without regard to the dividends paid deduction, excluding net capital gain and after theutilization of any available NOLs), to our stockholders. Our quarterly cash common stock dividend will delay the utilization of our NOLs and may causecertain of the NOLs to expire without utilization. See also "Item 7. MD&A—General Overview—Common Stock Dividend" and "Item 1. Business—CompanyDevelopments, REIT Status and Industry Update—REIT Status."As discussed in "Item 1. MD&A—Business—Strategy," we seek to invest our capital, including the net cash provided by our operating activities as wellas external financing sources, in a manner that we believe will increase long-term stockholder value on a risk-adjusted basis. Our historical discretionaryinvestments have included the following (in no particular order): acquiring or constructing communications infrastructure; acquiring land interests undertowers; improving or structurally enhancing our existing communications infrastructure; purchasing our common stock; or purchasing, repaying orredeeming our debt. External financing, including debt, equity, and equity-related issuances to fund future discretionary investments either (1) may not beavailable to us or (2) may not be accessible by us at terms that would result in the investment of the net proceeds raised yielding incremental growth in ourper share operating results. As a result, future dividend payments may hinder our ability to grow our per share results of operations or otherwise adverselyaffect our ability to execute our business plan.16Remaining qualified to be taxed as a REIT involves highly technical and complex provisions of the Code. Failure to remain qualified as a REIT wouldresult in our inability to deduct dividends to stockholders when computing our taxable income, which would reduce our available cash.We operate as a REIT for U.S. federal tax purposes. As a REIT, we are generally entitled to a deduction for dividends that we pay and therefore are notsubject to U.S. federal corporate income tax on our net taxable income that is currently distributed to our common stockholders.While we intend to operate so that we remain qualified as a REIT, given the highly complex nature of the rules governing REITs, the importance ofongoing factual determinations, the possibility of future changes in our circumstances, and the potential impact of future changes to laws and regulationsimpacting REITs, no assurance can be given that we will qualify as a REIT for any particular year.We do not expect the recently-enacted legislation commonly referred to as the Tax Reform Act to significantly affect us, although we cannot predictwith certainty how such legislation will affect us in the future. In addition, the present U.S. federal tax treatment of REITs is subject to change, possibly withretroactive effect, by legislative, judicial or administrative action at any time, and any such change might adversely affect our REIT status or benefits. Wecannot predict the impact, if any, that such changes, if enacted, might have on our business. However, it is possible that such changes could adversely affectour business, including our REIT status.If, in any taxable year, we fail to qualify for taxation as a REIT and are not entitled to relief under certain provisions of the the Code, then:•we will not be allowed a deduction for dividends paid to stockholders in computing our taxable income;•we will be subject to federal and state income tax, including, for applicable years beginning before January 1, 2018, any applicable alternativeminimum tax, on our taxable income at regular corporate rates; and•we would be disqualified from re-electing REIT status for the four taxable years following the year during which we were so disqualified.Although we may have federal NOLs available to reduce any taxable income, to the extent our federal NOLs have been utilized or are otherwiseunavailable, any such corporate tax liability could be substantial, would reduce the amount of cash available for other purposes and might necessitate theborrowing of additional funds or the liquidation of some investments to pay any additional tax liability. Accordingly, funds available for investment wouldbe reduced.Under the Code, for taxable years beginning before 2018, no more than 25% of the value of the assets of a REIT may be represented by securities of oneor more TRSs. For taxable years beginning in or after 2018, no more than 20% of the value of the assets of a REIT may be represented by securities of one ormore TRSs. These current or future limitations may affect our ability to make additional investments in non-REIT qualifying operations or assets, or in anyoperations held through TRSs. The net income of our TRSs is not required to be distributed to us, and income that is not distributed to us generally will notbe subject to the REIT income distribution requirement. However, there may be limitations on our ability to accumulate earnings in our TRSs and theaccumulation or reinvestment of significant earnings in our TRSs could result in adverse tax treatment. In particular, if the accumulation of cash in our TRSscauses the fair market value of our securities in our TRSs to exceed current or future limitations of the fair market value of our assets at the end of any quarter,then we may fail to remain qualified as a REIT.If we fail to pay scheduled dividends on our 6.875% Convertible Preferred Stock, in cash, common stock, or any combination of cash and common stock,we will be prohibited from paying dividends on our common stock, which may jeopardize our status as a REIT.The terms of the 6.875% Convertible Preferred Stock provide that, unless accumulated dividends have been paid or set aside for payment on alloutstanding 6.875% Convertible Preferred Stock for all past dividend periods, no dividends may be declared or paid on our common stock. If that were tooccur, the inability to pay dividends on our common stock might jeopardize our status as a REIT for U.S. federal income tax purposes. See note 12 to ourconsolidated financial statements.17Complying with REIT requirements, including the 90% distribution requirement, may limit our flexibility or cause us to forgo otherwise attractiveopportunities, including certain discretionary investments and potential financing alternatives.To remain qualified and be taxed as a REIT, we are required to satisfy the 90% distribution requirement as described above. We commenced declaringregular quarterly dividends to our common stockholders beginning with the first quarter of 2014. See notes 12 and 19 to our consolidated financialstatements. Any such dividends, however, are subject to the determination and approval of our board of directors based on then-current and anticipated futureconditions, including our earnings, net cash provided by operating activities, capital requirements, financial condition, our relative market capitalization, ourexisting federal NOLs of approximately $1.5 billion or other factors deemed relevant by our board of directors.To the extent that we satisfy the 90% distribution requirement, but distribute less than 100% of our REIT taxable income (determined without regard tothe dividends paid deduction, excluding net capital gain and after the utilization of any available NOLs), we will be subject to federal corporate income taxon our undistributed taxable income. In addition, we will be subject to a 4% nondeductible excise tax if the actual amount that we pay out to ourstockholders for a calendar year is less than a minimum amount specified under the Code.From time to time, we may generate REIT taxable income greater than our cash flow as a result of differences in timing between the recognition oftaxable income and the actual receipt of cash or the effect of nondeductible capital expenditures, the creation of reserves or required debt or amortizationpayments. If we do not have other funds available in these situations, we could be required to borrow funds on unfavorable terms, sell assets atdisadvantageous prices, or distribute amounts that would otherwise be invested in future acquisitions to make distributions sufficient to enable us to pay outenough of our taxable income to satisfy the REIT dividend requirement and to avoid corporate income tax and the 4% excise tax in a particular year. Thesealternatives could increase our costs or reduce our equity. Thus, compliance with the REIT requirements may hinder our ability to grow, which couldadversely affect the value of our common stock. Furthermore, the REIT dividend requirements may increase the financing we need to fund capitalexpenditures, future growth, or expansion initiatives, which would increase our total leverage.In addition to satisfying the 90% distribution requirement, to remain qualified as a REIT for tax purposes, we will need to continually satisfy testsconcerning, among other things, the sources of our income, the nature and diversification of our assets and the ownership of our capital stock. Compliancewith these tests will require us to refrain from certain activities and may hinder our ability to make certain attractive investments, including the purchase ofnon-qualifying assets, the expansion of non-real estate activities, or investments in the businesses to be conducted by our TRSs, and to that extent, limit ouropportunities and our flexibility to change our business strategy. Furthermore, acquisition opportunities in domestic or international markets may beadversely affected if we need or require the target company to comply with some REIT requirements prior to completing any such acquisition. In addition,our conversion to a REIT may result in investor pressures not to pursue growth opportunities that are not immediately accretive.Moreover, if we fail to comply with certain asset ownership tests, at the end of any calendar quarter, we must correct the failure within 30 days after theend of the calendar quarter or qualify for certain statutory relief provisions to avoid losing our REIT qualification. As a result, we may be required to liquidateassets in adverse market conditions or forgo otherwise attractive investments. These actions may reduce our income and amounts available for distribution toour stockholders.REIT related ownership limitations and transfer restrictions may prevent or restrict certain transfers of our capital stock.In order for us to continue to satisfy the requirements for REIT qualification, our capital stock must be beneficially owned by 100 or more personsduring at least 335 days of a taxable year of 12 months or during a proportionate part of a shorter taxable year. Also, not more than 50% of the value of theoutstanding shares of our capital stock may be owned, directly or indirectly, by five or fewer "individuals" (as defined in the Code to include certain entitiessuch as private foundations) during the last half of a taxable year. In order to facilitate compliance with the REIT rules, our Charter includes provisions thatimplement REIT-related ownership limitations and transfer restrictions that generally prohibit any "person" (as defined in our Charter) from beneficially orconstructively owning, or being deemed to beneficially or constructively own by virtue of the attribution provisions of the Code, more than 9.8%, by valueor number of shares, whichever is more restrictive, of the outstanding shares of our common stock, or 9.8% in aggregate value of the outstanding shares of allclasses and series of our capital stock, including our common stock and any shares of our 6.875% Convertible Preferred Stock. In addition, our Charterprovides for certain other ownership limitations and transfer restrictions. Under applicable constructive ownership rules, any shares of capital stock owned bycertain affiliated owners generally would be added together for purposes of the ownership limitations. These ownership limitations and transfer restrictionscould have the effect of delaying, deferring or preventing a transaction or a change in control of our company that might involve a premium price for ourcapital stock or otherwise might be in the best interest of our stockholders.18Available Information and CertificationsWe maintain a website at www.crowncastle.com. Our annual reports on Form 10-K, quarterly reports on Form 10-Q, and current reports on Form 8-K (andany amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended ("Exchange Act"))are made available, free of charge, through the investor relations section of our website at http://investor.crowncastle.com and at the SEC's website athttp://sec.gov as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. You may also read or copy anydocument we file with the SEC at the SEC's public reference room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 forfurther information on the public reference room.In addition, our corporate governance guidelines, business practices, ethics policy and financial code of ethics and the charters of our Audit Committee,Compensation Committee and Nominating & Corporate Governance Committee are available through the investor relations section of our website athttp://www.crowncastle.com/investor/corporateGovernance.aspx, and such information is also available in print to any stockholder who requests it.We submitted the Chief Executive Officer certification required by Section 303A.12(a) of the New York Stock Exchange ("NYSE") Listed CompanyManual, relating to compliance with the NYSE's corporate governance listing standards, to the NYSE on May 24, 2017 with no qualifications. We haveincluded the certifications of our Chief Executive Officer and Chief Financial Officer required by Section 302 of the Sarbanes-Oxley Act of 2002 and relatedrules as Exhibits 31.1 and 31.2 to this Annual Report on Form 10-K.19Item 1B. Unresolved Staff CommentsNone.Item 2. PropertiesOfficesOur principal corporate headquarters is owned and located in Houston, Texas. In addition, we have offices throughout the U.S. in locations convenientfor the management and operation of our communications infrastructure, with significant consideration being given to the amount of our communicationsinfrastructure located in a particular area. We believe that our facilities are suitable and adequate to meet our anticipated needs.Communications InfrastructureWe own, lease or manage approximately 40,000 towers geographically dispersed throughout the U.S. Towers are vertical metal structures generallyranging in height from 50 to 300 feet. Our customers' wireless equipment may be placed on towers, building rooftops and other structures. Our towers arelocated on tracts of land that support the towers, equipment shelters, and where applicable, guy-wires to stabilize the tower.Additionally, we own or lease approximately 60,000 route miles of fiber primarily supporting our small cells and fiber solutions. The majority of ourfiber assets are located in major metropolitan areas. Our small cells and fiber are typically located outdoors and are often attached to public right-of-wayinfrastructure, including utility poles or street lights.See "Item 1. Business—Overview" for (1) information regarding our tower portfolio including our land interests and for a discussion of the location ofour towers, including the percentage of our towers in the top 50 and 100 BTAs and tenants per tower and (2) information regarding our fiber portfolioincluding a discussion of the location of our fiber. See "Item 7. MD&A—Liquidity and Capital Resources—Contractual Cash Obligations" for a tabularpresentation of the remaining contractual obligations related to our business as of December 31, 2017.Approximately 53% of our towers are leased or subleased or operated and managed under master leases, subleases, or other agreements with AT&T,Sprint, and T-Mobile. We have the option to purchase these towers at the end of their respective lease terms. We have no obligation to exercise such purchaseoptions. See note 1 to our consolidated financial statements and "Item 1A. Risk Factors" for a further discussion.Substantially all of our communications infrastructure can accommodate additional tenancy, either as currently constructed or with appropriatemodifications. Additionally, if so inclined as a result of a request for a tenant addition, we could generally replace an existing tower with another tower,replace a small cell network antenna with another antenna or overlay additional fiber in order to provide additional coverage or capacity, subject to certainrestrictions.Item 3. Legal ProceedingsWe are periodically involved in legal proceedings that arise in the ordinary course of business. Most of these proceedings arising in the ordinary courseof business involve disputes with landlords, vendors, collection matters involving bankrupt customers, zoning or siting matters, condemnation, tax,employment, or wrongful termination matters. While the outcome of these matters cannot be predicted with certainty, management does not expect anypending matters to have a material adverse effect on us.Item 4. Mine Safety DisclosuresN/A20PART II Item 5.Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity SecuritiesPrice Range of Common StockOur common stock is listed and traded on the NYSE under the symbol "CCI." The following table sets forth for the calendar periods indicated the highand low sales prices per share of our common stock as reported by the NYSE. High (a) Low (a)2017: First Quarter$95.45 $83.96Second Quarter104.68 93.22Third Quarter108.88 93.14Fourth Quarter114.97 99.332016: First Quarter$88.46 $75.71Second Quarter101.44 85.59Third Quarter102.82 89.82Fourth Quarter95.84 79.38 (a)Prices per share reflect the high and low sale prices per share, unadjusted for common stock dividends declared and paid. See notes 12 and 19 to our consolidated financialstatements.As of February 21, 2018, there were approximately 180 holders of record of our common stock.Dividend PolicyWe operate as a REIT for U.S. federal income tax purposes. To remain qualified and be taxed as a REIT, we will generally be required to annuallydistribute to our stockholders at least 90% of our REIT taxable income after the utilization of any available NOLs (determined without regard to thedividends paid deduction and excluding net capital gain). See also "Item 7. MD&A—General Overview—Common Stock Dividend," "Item 1. Business—Company Developments, REIT Status and Industry Update—REIT Status," "Item 1A. Risk Factors" and notes 11 and 12 to our consolidated financialstatements.In aggregate, we paid approximately $1.2 billion in common stock dividends in 2016. During each of the first three quarters of 2016, we paid aquarterly common stock dividend of $0.885 per share, totaling approximately $896.6 million. In October 2016, we increased our quarterly dividend,beginning in the fourth quarter of 2016, from a quarterly amount of $0.885 per share to a quarterly amount of $0.95 per share. As such, we declared aquarterly dividend of $0.95 per share, or an annualized amount of $3.80 per share, in October 2016, which represented an increase of 7% from the quarterlydividend declared during each of the first three quarters of 2016.In aggregate, we paid approximately $1.5 billion in common stock dividends in 2017. During each of the first three quarters of 2017, we paid aquarterly common stock dividend of $0.95 per share, totaling approximately $1.1 billion. In October 2017, we increased our quarterly dividend, beginning inthe fourth quarter of 2017, from a quarterly amount of $0.95 per share to a quarterly amount of $1.05 per share. As such, we declared a quarterly dividend of$1.05 per share, or an annualized amount of $4.20 per share, in October 2017, which represented an increase of 11% from the quarterly dividend declaredduring each of the first three quarters of 2017. We currently expect such dividends to result in aggregate cash payments of at least $1.7 billion during the next12 months.Over time, we expect to increase our dividend per share generally commensurate with our realized growth in cash flows. The declaration amount andpayment of any future dividends, however, are subject to the determination and approval of our board of directors based on then-current or anticipated futureconditions, including our earnings, net cash provided by operating activities, capital requirements, financial condition, our relative market capitalization, ourexisting NOLs, or other factors deemed relevant by our board of directors. In addition, our ability to pay dividends is limited by the terms of our debtinstruments and our 6.875% Convertible Preferred Stock under certain circumstances. See "Item 7. MD&A—Liquidity and Capital Resources—FinancingActivities—Common Stock" and "Item 1A. Risk Factors."21Issuer Purchases of Equity SecuritiesThe following table summarizes information with respect to purchase of our equity securities during the fourth quarter of 2017:Period Total Number of SharesPurchased Average Price Paid perShare Total Number ofShares Purchased asPart of PubliclyAnnounced Plans orPrograms Maximum Number (orApproximate DollarValue) of Shares thatMay Yet Be PurchasedUnder the Plans orPrograms (In thousands) October 1 - October 31, 2017 — $— — —November 1 - November 30, 2017 2 106.82 — —December 1 - December 31, 2017 1 110.86 — —Total 3 $107.66 — —We paid $0.3 million in cash to effect these purchases. The shares purchased relate to shares withheld in connection with the payment of withholdingtaxes upon vesting of restricted stock.Equity Compensation PlansCertain information with respect to our equity compensation plans is set forth in "Item 12. Security Ownership of Certain Beneficial Owners andManagement" herein.22Performance GraphThe following performance graph is a comparison of the five year cumulative total stockholder return on our common stock against the cumulative totalreturn of the S&P 500 Market Index, the Dow Jones U.S. Telecommunications Equipment Index and the FTSE NAREIT All Equity REITs Index for the periodcommencing December 31, 2012 and ending December 31, 2017. The performance graph assumes an initial investment of $100.0 and the reinvestment of alldividends in our common stock and in each of the indices. The performance graph and related text are based on historical data and are not necessarilyindicative of future performance. Years Ended December 31,Company/Index/Market 2012 2013 2014 2015 2016 2017Crown Castle International Corp. $100.00 $101.76 $111.79 $127.81 $133.58 $177.57S&P 500 Market Index 100.00 132.39 150.51 152.59 170.84 208.14DJ US Telecommunications Equipment Index 100.00 121.43 139.90 124.79 148.67 182.95FTSE NAREIT All Equity REITs Index 100.00 102.85 131.68 136.58 146.94 159.69The performance graph above and related text are being furnished solely to accompany this Annual Report on Form 10-K pursuant to Item 201(e) ofRegulation S-K, and are not being filed for purposes of Section 18 of the Exchange Act, and are not to be incorporated by reference into any filing of ours,whether made before or after the date hereof, regardless of any general incorporation language in such filing.23Item 6. Selected Financial DataOur selected historical consolidated financial and other data set forth below have been derived from our consolidated financial statements. Theinformation set forth below should be read in conjunction with "Item 1. Business," "Item 7. MD&A" and our consolidated financial statements. Our formerly77.6% owned subsidiary that operated towers in Australia ("CCAL") is presented on a discontinued operations basis for all periods presented. See note 3 toour consolidated financial statements for further discussion of our sale of CCAL in May 2015. Years Ended December 31, 2017(a) 2016(a) 2015(a) 2014(a) 2013(a) (In thousands of dollars, except per share amounts) Statement of Operations Data: Net revenues: Site rental$3,669,191 $3,233,307 $3,018,413 $2,866,613 $2,371,380 Network services and other686,414 687,918 645,438 672,143 494,371 Net revenues4,355,605 3,921,225 3,663,851 3,538,756 2,865,751 Operating expenses: Costs of operations(b): Site rental1,143,914 1,023,350 963,869 906,152 686,873 Network services and other419,787 417,171 357,557 400,454 304,144 Total costs of operations1,563,701 1,440,521 1,321,426 1,306,606 991,017 General and administrative426,698 371,031 310,921 257,296 213,519 Asset write-down charges17,322 34,453 33,468 14,246 13,595 Acquisition and integration costs61,431 17,453 15,678 34,145 25,574 Depreciation, amortization and accretion1,242,408 1,108,551 1,036,178 985,781 741,342 Operating income (loss)1,044,045 949,216 946,180 940,682 880,704 Interest expense and amortization of deferred financing costs(590,682) (515,032) (527,128) (573,291) (589,630) Gains (losses) on retirement of long-term obligations(3,525) (52,291) (4,157) (44,629) (37,127) Interest income18,761 796 1,906 315 956 Other income (expense)1,994 (8,835) 57,028 11,993 (3,902) Income (loss) from continuing operations before income taxes470,593 373,854 473,829 335,070 251,001 Benefit (provision) for income taxes(c)(26,043) (16,881) 51,457 11,244 (191,000) Income (loss) from continuing operations444,550 356,973 525,286 346,314 60,001 Discontinued operations: Income (loss) from discontinued operations, net of tax— — 19,690 52,460 33,900 Net gain (loss) from disposal of discontinued operations, net of tax— — 979,359 — — Income (loss) from discontinued operations, net of tax— — 999,049 52,460 33,900 Net income (loss)444,550 356,973 1,524,335 398,774 93,901 Less: Net income (loss) attributable to the noncontrolling interest— — 3,343 8,261 3,790 Net income (loss) attributable to CCIC stockholders444,550 356,973 1,520,992 390,513 90,111 Dividends on preferred stock and losses on purchases of preferred stock(58,294) (32,991) (43,988) (43,988) (11,363) Net income (loss) attributable to CCIC common stockholders$386,256 $323,982 $1,477,004 $346,525 $78,748 Income (loss) from continuing operations attributable to CCIC commonstockholders, per common share - basic(d)$1.01 $0.95 $1.45 $0.91 $0.16 Income (loss) from continuing operations attributable to CCIC commonstockholders, per common share - diluted(d)$1.01 $0.95 $1.44 $0.91 $0.16 Weighted-average common shares outstanding (in thousands): Basic(d)(e)381,740 340,349 333,002 332,302 298,083 Diluted(d)(e)383,221 340,879 334,062 333,265 299,293 Dividends/distributions declared per share of common stock$3.90 $3.61 $3.35 $1.87 $— 24 Years Ended December 31, 2017(a) 2016(a) 2015(a) 2014(a) 2013(a) (In thousands of dollars, except per share amounts) Other Data: Summary cash flow information: Net cash provided by (used for) operating activities$2,044,186 $1,782,264 $1,794,025 $1,600,197 $1,171,059 Net cash provided by (used for) investing activities(10,494,021) (1,410,232) (1,959,734) (1,216,709) (5,459,285) Net cash provided by (used for) financing activities8,195,152 (96,292) (935,476) (462,987) 4,063,133 Ratio of earnings to fixed charges(f)1.5 1.5 1.6 1.4 1.3 Ratio of earnings to combined fixed charges and preferredstock dividends and losses on purchases of preferredstock(f)1.4 1.4 1.5 1.3 1.3 Balance Sheet Data (at period end): Cash and cash equivalents$314,094 $567,599 $178,810 $151,312 $200,526 Property and equipment, net12,932,885 9,805,315 9,580,057 8,982,783 8,764,031 Total assets32,229,570 22,675,092 21,936,966 21,026,827 20,466,028 Total debt and other long-term obligations16,159,620 12,171,142 12,149,959 11,804,412 11,465,620 Total CCIC stockholders' equity(e)(g)12,339,082 7,557,115 7,089,221 6,716,225 6,926,717 (a)Inclusive of the impact of acquisitions. See note 4 to our consolidated financial statements for a discussion of our acquisitions during 2015, 2016 and 2017. In addition, during2014, we acquired several portfolios of land interests under towers and during 2013, we acquired rights to approximately 9,100 towers through the AT&T Acquisition.(b)Exclusive of depreciation, amortization and accretion, which are shown separately.(c)See note 11 to our consolidated financial statements regarding our income taxes, including our REIT status.(d)Basic net income (loss) attributable to CCIC common stockholders, per common share, excludes dilution and is computed by dividing net income (loss) attributable to CCICcommon stockholders by the weighted-average number of common shares outstanding during the period. Diluted net income (loss) attributable to CCIC common stockholders,per common share is computed by dividing net income (loss) attributable to CCIC common stockholders by the weighted-average number of common shares outstanding duringthe period, plus any potential dilutive common share equivalents, including shares issuable (1) upon the vesting of restricted stock awards and restricted stock units as determinedunder the treasury stock method and (2) upon conversion of convertible preferred stock securities (including the currently outstanding 6.875% Convertible Preferred Stock,which was issued in 2017, and the formerly outstanding 4.50% Mandatory Convertible Preferred Stock, Series A, par value $0.01 per share ("4.50% Convertible PreferredStock") which was issued in 2013 and converted to common stock in 2016), as determined under the if-converted method. See note 2 to our consolidated financial statements.(e)During 2017, we issued shares of our common stock in connection with (1) our May 2017 issuance of 4.75 million shares of common stock, which generated net proceeds of$442 million ("May 2017 Common Stock Offering") to partially fund the Wilcon Acquisition in June 2017, (2) our July 2017 issuance of 40.15 million shares of common stock,which generated approximately $3.8 billion ("July 2017 Common Stock Offering") to partially fund the Lightower Acquisition in November 2017 and (3) our ATM Program.During 2016, we issued shares of our common stock in connection with (1) our ATM Program, the proceeds of which we utilized to partially fund our acquisition of TowerDevelopment Corporation ("TDC Acquisition") in April 2016, (2) the conversion of our then outstanding 4.50% Convertible Preferred Stock to common stock and (3) ourNovember 2016 issuance of 11.4 million shares of common stock, which generated net proceeds of $1.0 billion ("November 2016 Common Stock Offering") to partially fund theFiberNet Acquisition. See note 12 to our consolidated financial statements. In October 2013, we issued 41.4 million shares of common stock, which generated net proceeds of$3.0 billion to partially fund the AT&T Acquisition.(f)For purposes of computing the ratio of earnings to fixed charges, earnings represent income (loss) before income taxes and fixed charges less interest capitalized. Fixed chargesconsist of interest expense, amortized premiums, discounts and capitalized expenses related to indebtedness, interest capitalized and the interest component of operating leaseexpense.(g)During 2017, we issued 1.65 million shares of 6.875% Convertible Preferred Stock, which generated net proceeds of approximately $1.6 billion ("6.875% Convertible PreferredStock Offering") to partially fund the Lightower Acquisition in November 2017. During 2013, we issued 9.8 million shares of 4.50% Convertible Preferred Stock, whichgenerated net proceeds of $950.9 million to partially fund the AT&T Acquisition.25Item 7. Management's Discussion and Analysis of Financial Condition and Results of OperationsGeneral OverviewOverviewWe own, operate, and lease shared communications infrastructure. See "Item 1. Business" for a further discussion of our business, including our long-term strategy, our REIT status, certain key terms of our contracts and growth trends in the demand for data. Site rental revenues represented 84% of our 2017consolidated net revenues. The vast majority of our site rental revenues is of a recurring nature and has been contracted for in a prior year.Business Fundamentals and ResultsThe following are certain highlights of our business fundamentals and results:•We operate as a REIT for U.S. federal income tax purposes (see "Item 1. Business—Company Developments, REIT Status and Industry Updates—REIT Status" and note 11 to our consolidated financial statements).•Potential growth resulting from the increasing demand for data◦We expect wireless carriers will continue their focus on improving network quality and expanding capacity by utilizing a combination oftowers and small cells. We believe our product offerings of towers and small cells provide a comprehensive solution to our wireless customers'growing communications infrastructure needs.◦We expect organizations will continue to increase the usage of high-bandwidth applications that will require the utilization of more fiberinfrastructure and solutions such as those we provide.◦Within our Fiber segment, we are able to generate growth and returns for our stockholders by deploying our fiber for both small cells and fibersolutions customers.◦We expect existing and potential new customer demand for our communications infrastructure will result from (1) new technologies, (2)increased usage of mobile entertainment, mobile internet usage, and machine-to-machine applications, (3) adoption of other emerging andembedded wireless devices (including smartphones, laptops, tablets, and other devices), (4) increasing smartphone penetration, (5) wirelesscarrier focus on expanding both network quality and capacity, including the use of both towers and small cells, (6) the adoption of otherbandwidth-intensive applications (such as cloud services and video communications) and (7) the availability of additional spectrum.◦Tenant additions on our existing communications infrastructure are achieved at a low incremental operating cost, delivering high incrementalreturns.•Substantially all of our communications infrastructure can accommodate additional tenancy, either as currently constructed or withappropriate modifications.◦U.S. wireless carriers continue to invest in their networks.•Site rental revenues under long-term tenant contracts◦Initial terms of five to 15 years for site rental revenues derived from wireless customers, with contractual escalations and multiple renewalperiods at the option of the tenant of five to ten years each.◦Initial terms that generally vary between three to 20 years for site rental revenues derived from our fiber solutions business (including fromorganizations with high-bandwidth and multi-location demands).◦Weighted-average remaining term of approximately five years, exclusive of renewals at the tenants' option, currently representingapproximately $22 billion of expected future cash inflows.•Revenues predominately from large wireless carriers◦Approximately 83% of our site rental revenues were derived from AT&T, T-Mobile, Verizon Wireless and Sprint. See also "Item 1A. RiskFactors" and note 16 to our consolidated financial statements.•Majority of land interests under our towers are under long-term control◦Approximately 90% of our Towers site rental gross margin and more than 75% of our Towers site rental gross margin is derived from towersthat reside on land that we own or control for greater than ten and 20 years, respectively. The aforementioned amounts include towers thatreside on land interests that are owned, including fee interests and perpetual easements, which represent over one-third of our Towers siterental gross margin.•Majority of our fiber assets are located on public rights-of-way•Minimal sustaining capital expenditure requirements◦Sustaining capital expenditures represented approximately 2% of net revenues.•Debt portfolio with long-dated maturities extended over multiple years, with the majority of such debt having a fixed rate (see "Item 7A.Quantitative and Qualitative Disclosures About Market Risk" for a further discussion of our debt)◦After giving effect to our January 2018 issuance of $750.0 million aggregate principal amount of 3.150% senior unsecured notes due July2023 ("3.150% Senior Notes") and $1.0 billion aggregate principal amount of 3.800%26senior unsecured notes due February 2028 ("3.800% Senior Notes") (collectively, "January 2018 Senior Notes") and the application of the netproceeds therefrom, 82% of our debt has fixed rate coupons.◦Our debt service coverage and leverage ratios were comfortably within their respective financial maintenance covenants. See "Item 7. MD&A—Liquidity and Capital Resources—Debt Covenants" for a further discussion of our debt covenants.◦During 2017, we completed several debt transactions in connection with our 2017 Acquisitions and to refinance and extend the maturities ofcertain of our debt. As of December 31, 2017, after giving effect to our January 2018 Senior Notes offering and application of the net proceedstherefrom, our outstanding debt has a weighted average interest rate of 3.8% and weighted average maturity of greater than six years(assuming anticipated repayment dates where applicable). See "Item 7. MD&A—Liquidity and Capital Resources—Financing Activities" forfurther discussion of our debt transactions.•Significant cash flows from operations◦Net cash provided by operating activities was $2.0 billion.◦In addition to the positive impact of contractual escalators, we expect to grow our core business of providing access to our communicationsinfrastructure as a result of future anticipated additional demand for our communications infrastructure.•Returning cash flows provided by operations to stockholders in the form of dividends (see also "Item 1. Business—Strategy")◦During 2017, we paid common stock dividends totaling approximately $1.5 billion. See "Item 7. MD&A—General Overview—Common StockDividend" for a discussion of the increase to our quarterly dividend in the fourth quarter of 2017.•During 2017, we issued shares of our common stock and 6.875% Convertible Preferred Stock in connection with our 2017 Acquisitions (see "Item7. MD&A—Liquidity and Capital Resources—Financing Activities" for further discussion).•Investing capital efficiently to grow long-term dividends per share (see also "Item 1. Business")◦Discretionary capital expenditures of $1.1 billion, including communications infrastructure improvements in order to support additional siterentals, construction of communications infrastructure and land purchases.◦See below and note 4 to our consolidated financial statements for a discussion of our 2017 Acquisitions.•As a result of our 2017 Acquisitions of fiber assets (as further described in note 4 to our consolidated financial statements), we changed the nameof our "Small Cells" operating segment to "Fiber." We changed the name of this segment to reflect our strategy of utilizing the same fiber assets toprovide both small cells and fiber solutions to our customers. The name change did not impact the composition or the previously-reportedoperating results of the Fiber segment. As such, our operating segments are now referred to as "Towers" and "Fiber."Common Stock DividendIn aggregate, we paid approximately $1.5 billion in common stock dividends in 2017. During each of the first three quarters of 2017, we paid aquarterly common stock dividend of $0.95 per share, totaling approximately $1.1 billion. In October 2017, we increased our quarterly dividend, beginning inthe fourth quarter of 2017, from a quarterly amount of $0.95 per share to a quarterly amount of $1.05 per share. As such, we declared a quarterly dividend of$1.05 per share, or an annualized amount of $4.20 per share, in October 2017, which represented an increase of 11% from the quarterly dividend declaredduring each of the first three quarters of 2017. We currently expect such dividends to result in aggregate annual cash payments of at least $1.7 billion duringthe next 12 months, or an annualized amount of $4.20 per share. Over time, we expect to increase our dividend per share generally commensurate with ourrealized growth in cash flows. Any future dividends are subject to the approval of our board of directors. See notes 12 and 19 to our consolidated financialstatements.FiberNet AcquisitionOn November 1, 2016, we entered into a definitive agreement to acquire FPL FiberNet Holdings, LLC and certain other subsidiaries of NextEra Energy,Inc. (collectively, "FiberNet") for approximately $1.5 billion in cash, subject to certain limited adjustments. FiberNet is a fiber services provider in Floridaand Texas that owns or has rights to approximately 11,500 route miles of fiber installed and under construction, inclusive of approximately 6,000 route milesin top metro markets. On January 17, 2017, we closed the FiberNet Acquisition, which was financed using proceeds from our November 2016 Common StockOffering and borrowings under the 2016 Revolver. See notes 4, 8 and 12 to our consolidated financial statements.Wilcon AcquisitionOn April 17, 2017, we entered into a definitive agreement to acquire Wilcon Holdings LLC ("Wilcon") from Pamlico Holdings and other unit holders ofWilcon for approximately $600 million in cash, subject to certain limited adjustments ("Wilcon Acquisition"). Wilcon is a fiber services provider that ownsapproximately 1,900 route miles of fiber, primarily in Los Angeles27and San Diego. On June 26, 2017, we closed the Wilcon Acquisition, which was financed using proceeds from the May 2017 Common Stock Offering and the4.750% Senior Notes (as defined in note 8 to our consolidated financial statements) offering. See notes 4, 8 and 12 to our consolidated financial statements.Lightower AcquisitionOn July 18, 2017, we entered into a definitive agreement to acquire LTS Group Holdings LLC ("Lightower") for approximately $7.1 billion in cash,subject to certain limited adjustments. Lightower owns or has rights to approximately 32,000 route miles of fiber located primarily in top metro markets inthe Northeast, including Boston, New York and Philadelphia. On November 1, 2017, we closed the Lightower Acquisition, which was financed using (1) cashon hand, including the proceeds from the July 2017 Equity Offerings (as defined in note 12 to our consolidated financial statements) and August 2017 SeniorNotes (as defined in note 8 to our consolidated financial statements) offering, and (2) borrowings under the 2016 Revolver. See notes 4, 8 and 12 to ourconsolidated financial statements.Outlook HighlightsThe following are certain highlights of our 2018 outlook that impact our business fundamentals described above.•We expect that our full year 2018 site rental revenue growth will be impacted by (1) the 2017 Acquisitions (see note 4 to our consolidatedfinancial statements) and (2) a healthy environment for tenant additions, as large wireless carriers and fiber solutions customers attempt to meet theincreasing demand for data. See note 15 to our consolidated financial statements.•We expect discretionary capital expenditures for 2018 to exceed 2017 levels with a continued increase in the construction of new small cells andfiber as a result of the anticipated returns on such discretionary investments. We also expect sustaining capital expenditures of approximately 2%of net revenues for full year 2018.28Results of OperationsThe following discussion of our results of operations should be read in conjunction with "Item 1. Business," "Item 7. MD&A—Liquidity and CapitalResources" and our consolidated financial statements.The following discussion of our results of operations is based on our consolidated financial statements prepared in accordance with generally acceptedaccounting principles in the U.S. ("GAAP") which require us to make estimates and judgments that affect the reported amounts (see "Item 7. MD&A—Accounting and Reporting Matters—Critical Accounting Policies and Estimates" and note 2 to our consolidated financial statements).Our operating segments consist of (1) Towers and (2) Fiber. See note 16 to our consolidated financial statements for further discussion of our operatingsegments.See "Item 7. MD&A—Accounting and Reporting Matters—Non-GAAP and Segment Financial Measures" for a discussion of our use of (1) segment siterental gross margin, (2) segment network services and other gross margin, (3) segment operating profit, including their respective definitions and (4) AdjustedEBITDA, including its definition, and a reconciliation to net income.Highlights of our results of operations for 2017, 2016 and 2015 are depicted below: Years Ended December 31, Percent Change 2017 2016 2015 2017vs.2016 2016vs.2015 (In thousands of dollars) Site rental revenues: Towers site rental revenues$2,899,554 $2,830,708 $2,734,045 2 % 4 %Fiber site rental revenues769,637 402,599 284,368 91 % 42 %Total site rental revenues3,669,191 3,233,307 3,018,413 13 % 7 %Site rental gross margin: Towers site rental gross margin(a)2,054,759 1,990,499 1,906,870 3 % 4 %Fiber site rental gross margin(a)505,578 255,140 177,173 98 % 44 %Network services and other gross margin: Towers network services and other gross margin(a)262,398 259,094 282,630 1 % (8)%Fiber network services and other gross margin(a)9,191 19,370 10,621 (53)% 82 %Segment operating profit: Towers operating profit(a)2,223,495 2,156,690 2,097,601 3 % 3 %Fiber operating profit(a)425,721 213,834 149,415 99 % 43 %Adjusted EBITDA(b)2,481,761 2,227,523 2,119,183 11 % 5 %Net income attributable to CCIC common stockholders386,256 323,982 1,477,004 19 % (78)% (a)See note 16 to our consolidated financial statements for our definitions of segment site rental gross margin, segment network services and other gross margin and segmentoperating profit.(b)See reconciliation of Adjusted EBITDA in "Item 7. MD&A—Accounting and Reporting Matters—Non-GAAP and Segment Financial Measures."292017 and 2016.Total site rental revenues for 2017 grew $435.9 million, or 13%, from 2016. This increase was predominately comprised of the factors depicted in thechart below:($ in millions) (a)Includes amortization of upfront payments received from long-term tenant contracts and other deferred credits (commonly referred to as prepaid rent).(b)Represents initial contribution of acquisitions and tower builds until the one-year anniversary of the acquisition or build.Towers site rental revenues for 2017 were approximately $2.9 billion and increased by $68.8 million, or 2%, from approximately $2.8 billion during2016. The increase in Towers site rental revenues was impacted by the following items, inclusive of straight-line accounting: tenant additions across ourentire portfolio, renewals or extensions of tenant contracts, escalations, and non-renewals of tenants contracts. Tenant additions were influenced by ourcustomers' ongoing efforts to improve network quality and capacity.Fiber site rental revenues for 2017 were $769.6 million and increased by $367.0 million, or 91%, from $402.6 million from 2016. The increase in Fibersite rental revenues was predominately impacted by (1) $144.6 million from the FiberNet Acquisition in January 2017, (2) $26.3 million from the WilconAcquisition in June 2017, (3) $140.3 million from the Lightower Acquisition in November 2017 and (4) the increased demand for small cells and fibersolutions. Increased demand for small cells and fiber solutions was influenced by our customers' growing adoption of small cells and fiber solutions as animportant component of their network strategy in an effort to provide capacity, relieve network congestion and meet the increasing demand for data.The increase in Towers site rental gross margin from 2016 to 2017 was related to the previously-mentioned 2% increase in Towers site rental revenuesand relatively fixed costs to operate our towers. The increase in Fiber site rental gross margins was predominately related to the previously-mentioned 91%increase in Fiber site rental revenues.Towers network services and other gross margin was $262.4 million for 2017 and increased by $3.3 million, or 1%, from $259.1 million in 2016, whichis a reflection of (1) the volume of activity from carrier network enhancements and (2) the volume and mix of network services and other work. Our networkservices and other offerings are of a variable nature as these revenues are not under long-term contracts.General and administrative expenses for 2017 were $426.7 million and increased by $55.7 million, or 15%, from $371.0 million during 2016. Theincrease in general and administrative expenses was primarily related to the growth in our Fiber business, including the 2017 Acquisitions.30Towers operating profit for 2017 increased by $66.8 million, or 3%, from 2016. Towers operating profit was primarily reflecting the growth in ourTowers site rental revenues and relatively fixed costs to operate our towers.Fiber operating profit for 2017 increased by $211.9 million, or 99%, from 2016. Fiber operating profit was positively impacted by the previously-mentioned 2017 Acquisitions and the increased demand for small cells and fiber solutions as described above.Depreciation, amortization and accretion was approximately $1.2 billion for the 2017 and increased by $133.9 million, or 12%, from approximately$1.1 billion during 2016. This increase predominately resulted from a corresponding increase in our gross property and equipment due to capitalexpenditures and acquisitions, including the 2017 Acquisitions as discussed above.Interest expense and amortization of deferred financing costs were $590.7 million for 2017 and increased by $75.7 million, or 15%, from $515.0million during 2016. The increase predominately resulted from a corresponding increase in our outstanding indebtedness due to the financing of our 2017Acquisitions. See notes 4 and 8 to our consolidated financial statements.As a result of repaying certain of our debt, in conjunction with our refinancing activities, we incurred losses of $3.5 million and $52.3 million during2017 and 2016, respectively. For a further discussion of the debt refinancings, see note 8 to our consolidated financial statements, "Item 7. MD&A—Liquidityand Capital Resources" and "Item 7A. Quantitative and Qualitative Disclosures About Market Risk."The provision for income taxes for 2017 and 2016 were $26.0 million and $16.9 million, respectively. For both 2017 and 2016, the effective tax ratediffers from the federal statutory rate predominately due to (1) our REIT status, including the dividends paid deduction and (2) a non-cash tax provision of$14.6 million as a result of the enactment of the Tax Reform Act. See "Item 1. Business——Company Developments, REIT Status and Industry Update—REITStatus," "Item 7. MD&A—Accounting and Reporting Matters—Critical Accounting Policies and Estimates" and note 11 to our consolidated financialstatements.Net income (loss) attributable to CCIC stockholders was income of $444.6 million during 2017 compared to income of $357.0 million during 2016.The increase was predominately related to net growth in both our Towers and Fiber segments as well as a decrease in the losses on retirement of long-termobligations, partially offset by an increase in expenses, including (1) interest expense and amortization of deferred financing costs, (2) depreciation,amortization and accretion and (3) general and administrative expenses.Adjusted EBITDA increased $254.2 million, or 11%, from 2016 to 2017, reflecting the growth in our site rental activities in both Towers and Fiber,including the 2017 Acquisitions as discussed above.312016 and 2015.Total site rental revenues for 2016 grew $214.9 million, or 7%, from 2015. This increase was predominately comprised of the factors depicted in thechart below:($ in millions) (a)Includes amortization of upfront payments received from long-term tenant contracts and other deferred credits (commonly referred to as prepaid rent).(b)Represents initial contribution of acquisitions and tower builds until the one-year anniversary of the acquisition or build.Towers site rental revenues for 2016 were approximately $2.8 billion and increased by $96.7 million, or 4%, from approximately $2.7 billion during2015. The increase in Towers site rental revenues was impacted by the following items, inclusive of straight-line accounting: tenant additions across ourentire portfolio, renewals or extensions of tenant contracts, acquisitions (including the TDC Acquisition (as defined in note 4 to our consolidated financialstatements) in April 2016), escalations and non-renewals of tenant contracts predominately arising from our customers' decommissioning of the AcquiredNetworks. Tenant additions were influenced by our customers' ongoing efforts to improve network quality and capacity.Fiber site rental revenues for 2016 were $402.6 million and increased by $118.2 million, or 42%, from $284.4 million in 2015. The increase in Fiber siterental revenues was predominately impacted by (1) the Sunesys Acquisition completed in August 2015 and (2) the increased demand for newly-constructedsmall cells. Increased demand for small cells was influenced by our customers' growing adoption of small cells as an important component of their networkstrategy to provide capacity and relieve network congestion.The increase in Towers site rental gross margin from 2015 to 2016 was related to the previously-mentioned 4% increase in Towers site rental revenuesand relatively fixed costs to operate our towers. The increase in Fiber site rental gross margins was predominately related to the previously-mentioned 42%increase in Fiber site rental revenues.Towers network services and other gross margin was $259.1 million for 2016 and decreased by $23.5 million, or 8%, from $282.6 million in 2015,which is a reflection of (1) the volume of activity from carrier network enhancements and (2) the volume and mix of network services and other work. Ournetwork services and other offerings are of a variable nature as these revenues are not under long-term contracts.General and administrative expenses for 2016 were $371.0 million and increased by $60.1 million, or 19%, from 2015. General and administrativeexpenses are inclusive of stock-based compensation charges, which increased $29.4 million from 2015 to 2016. The increase in general and administrativeexpenses was primarily related to the growth in our Fiber business, including the Sunesys Acquisition.32Towers operating profit for 2016 increased by $59.1 million, or 3%, from 2015. Towers operating profit was primarily reflecting the growth in ourTowers site rental revenues and relatively fixed costs to operate our towers.Fiber operating profit for 2016 increased by $64.4 million, or 43%, from 2015 and was positively impacted by the previously-mentioned SunesysAcquisition and the leasing of newly constructed small cells.Depreciation, amortization and accretion was approximately $1.1 billion for 2016 and increased by $72.4 million, or 7%, from approximately $1.0billion during 2015. This increase predominately resulted from a corresponding increase in our gross property and equipment due to capital expenditures andacquisitions, including the Sunesys Acquisition.Interest expense and amortization of deferred financing costs were $515.0 million for 2016 and decreased by $12.1 million, or 2%, from $527.1 millionduring 2015. This decrease is predominately the result of a $18.7 million decrease in the amortization of interest rate swaps.As a result of repaying and redeeming certain of our debt, in conjunction with our refinancing activities, we incurred net losses of $52.3 million and$4.2 million for 2016 and 2015, respectively. For a further discussion of the debt refinancings, see note 8 to our consolidated financial statements, "Item 7.MD&A—Liquidity and Capital Resources" and "Item 7A. Quantitative and Qualitative Disclosures About Market Risk."Other income (expense) for 2016 was income of $8.8 million, compared to income of $57.0 million for 2015. This change was predominately a result ofgains recorded during 2015 on foreign currency swaps that we entered into to manage and reduce our foreign currency risk related to our May 2015 sale ofCCAL. See note 9 to our consolidated financial statements.The benefit (provision) for income taxes for 2016 was a provision of $16.9 million compared to a benefit of $51.5 million for 2015. For 2016, theeffective tax rate differed from the federal statutory rate predominately due to our REIT status, including the dividends paid deduction. For 2015, theeffective tax rate differed from the federal statutory rate predominately due to (1) our REIT status, including the dividends paid deduction, and (2) the de-recognition of net deferred tax liabilities related to the inclusion of small cells in the REIT in January 2016, which resulted in a non-cash income tax benefitof $33.8 million. See "Item 7. MD&A—Accounting and Reporting Matters—Critical Accounting Policies and Estimates" and note 11 to our consolidatedfinancial statements.Income from discontinued operations, net of tax, decreased from 2015 to 2016 due to the sale of CCAL occurring mid-period on May 28, 2015. Inaddition, during 2015, we recorded a gain on the sale of discontinued operations, net of tax, of approximately $1.0 billion.Net income (loss) attributable to CCIC stockholders for 2016 was income of $357.0 million compared to income of approximately $1.5 billion for2015. The decrease in net income was predominately due to the gain recorded on the sale of CCAL of approximately $1.0 billion.Adjusted EBITDA increased by $108.3 million, or 5%, from 2015 to 2016. Adjusted EBITDA was (1) positively impacted by the growth in our siterental activities in both Towers and Fiber and (2) negatively impacted by a decrease in Towers network services and other gross margin.Liquidity and Capital ResourcesOverviewGeneral. Our core business generates revenues under long-term contracts (see "Item 1. Business—Overview" and "Item 7. MD&A—General Overview—Overview") from the largest U.S. wireless carriers and fiber solutions customers. Our strategy is to create long-term stockholder value via a combination of (1)growing cash flows generated from our portfolio of communications infrastructure, (2) returning a meaningful portion of our cash provided by operatingactivities to our stockholders in the form of dividends and (3) investing capital efficiently to grow cash flows and long-term dividends per share. We measureour efforts to create "long-term stockholder value" by the combined payment of dividends to stockholders and growth in our per share results. See "Item 1.Business—Strategy" for a further discussion of our strategy.We have engaged and expect to continue to engage in discretionary investments that we believe will maximize long-term stockholder value. Ourhistorical discretionary investments include (in no particular order): acquiring or constructing communications infrastructure, acquiring land interests undertowers, improving and structurally enhancing our existing communications infrastructure, purchasing our common stock, and purchasing, repaying orredeeming our debt. We have recently spent and expect to continue to spend a significant percentage of our discretionary investments on the construction ofnew small cells and fiber. We seek to fund our discretionary investments with both net cash provided by operating activities and cash available33from financing capacity, such as the use of our undrawn availability from the 2016 Revolver, debt financings and issuances of equity or equity relatedsecurities, including under our ATM Program.We seek to maintain a capital structure that we believe drives long-term stockholder value and optimizes our weighted-average cost of capital. Wetarget a leverage ratio of approximately four to five times Adjusted EBITDA and interest coverage of approximately three times Adjusted EBITDA, subject tovarious factors such as the availability and cost of capital and the potential long-term return on our discretionary investments. We may choose to increase ordecrease our leverage or coverage from these targets for various periods of time.We operate as a REIT for U.S. federal income tax purposes. We expect to continue to pay minimal cash income taxes as a result of our REIT status andour NOLs. See "Item 1. Business—Company Developments, REIT Status and Industry Update—REIT Status," "Item 7. MD&A—General Overview" and note 11to our consolidated financial statements.Liquidity Position. The following is a summary of our capitalization and liquidity position as of December 31, 2017, after giving effect to the January2018 Senior Notes offering and the application of proceeds therefrom. See "Item 7A. Quantitative and Qualitative Disclosures About Market Risk" and notes8 and 19 to our consolidated financial statements for additional information regarding our debt. (In thousands of dollars)Cash and cash equivalents(a)$316,647Undrawn revolving credit facility availability(b)2,910,967Restricted cash126,065Debt and other long-term obligations16,233,734Total equity12,267,599 (a)Exclusive of restricted cash.(b)Availability at any point in time is subject to certain restrictions based on the maintenance of financial covenants contained in the 2016 Credit Facility.See "Item 7. MD&A—Liquidity and Capital Resources—Financing Activities" and "Item 7. MD&A—Liquidity and Capital Resources—Debt Covenants."Over the next 12 months:•Our liquidity sources may include (1) cash on hand, (2) net cash provided by operating activities, (3) undrawn availability from our 2016 Revolverand (4) issuances of equity pursuant to our ATM Program. Our liquidity uses over the next 12 months are expected to include (1) debt serviceobligations of approximately $116.0 million (principal payments), (2) common stock dividend payments expected to be at least $4.20 per share, oran aggregate of at least $1.7 billion, subject to future approval by our board of directors (see "Item 7. MD&A—General Overview—Common StockDividend"), (3) 6.875% Convertible Preferred Stock dividend payments of approximately $113 million and (4) capital expenditures (expected to begreater than current levels). During the next 12 months, while our liquidity uses are expected to exceed our net cash provided by our operatingactivities, we expect that our liquidity sources described above should be sufficient to cover our expected uses. As CCIC is a holding company, thiscash flow from operations is generated by our operating subsidiaries.•We have no scheduled contractual debt maturities other than principal payments on amortizing debt. See "Item 7A. Quantitative and QualitativeDisclosures About Market Risk" for a tabular presentation of our debt maturities as of December 31, 2017 and a discussion of anticipated repaymentdates.Summary Cash Flows Information Years Ended December 31, 201720162015 (In thousands of dollars)Net cash provided by (used for): Operating activities$2,044,186 $1,782,264 $1,794,025Investing activities(10,494,021) (1,410,232) (1,959,734)Financing activities8,195,152 (96,292) (935,476)Net increase (decrease) in cash and cash equivalents - continuing operations(254,683) 275,740 (1,101,185)Discontinued operations (see note 3): Net cash provided by (used for) operating activities— — 2,700Net cash provided by (used for) investing activities— 113,150 1,103,577Net increase (decrease) in cash and cash equivalents - discontinued operations— 113,150 1,106,27734Operating Activities. The increase in net cash provided by operating activities for 2017 from 2016 was due primarily to growth in our core business,including a net benefit from changes in working capital. The decrease in net cash provided by operating activities for 2016 from 2015 was due primarily to anet decrease in working capital, partially offset by growth in our core business. Changes in working capital (including changes in accounts receivable,deferred site rental receivables, deferred rental revenues, prepaid ground leases, restricted cash and accrued interest) can have a significant impact on net cashprovided by operating activities, largely due to the timing of advanced payments by us and advanced receipts. We expect to grow our net cash provided byoperating activities in the future (exclusive of movements in working capital) if we realize expected growth in our core business.Investing Activities. Historically, our capital expenditures have been categorized as discretionary or sustaining, as described below.•Discretionary capital expenditures are those capital expenditures made with respect to activities which we believe exhibit sufficient potential toenhance long-term stockholder value. They consist of expansion or development of existing communications infrastructure, construction of newcommunications infrastructure, and, to a lesser extent, purchases of land assets under towers as we seek to manage our interests in the land beneathour towers. The expansion or development of existing communications infrastructure to accommodate tenant additions typically vary based on,among other factors: (1) the type of communications infrastructure, (2) the scope, volume, and mix of work performed on the communicationsinfrastructure, (3) existing capacity prior to installation or (4) changes in structural engineering regulations and standards. Construction of newcommunications infrastructure is predominately comprised of the construction of small cells and fiber. Our decisions regarding discretionary capitalexpenditures are influenced by the availability and cost of capital and expected returns on alternative uses of cash, such as payments of dividendsand investments.•Sustaining capital expenditures consist of (1) corporate capital expenditures and (2) capital improvements on our communications infrastructureassets that enable our customers' ongoing quiet enjoyment of the communications infrastructure.We anticipate incurring initial capital expenditures related to integrating Lightower into our existing business. We anticipate that the majority of theseexpected capital expenditures will be incurred beginning in 2018 and will primarily relate to the integration of Lightower's information technology assetsinto our business. Integration capital expenditures were $3.6 million and $0.1 million for the years ended December 31, 2017 and 2016, respectively. Assuch, for periods presented prior to 2018, integration capital expenditures were included within sustaining capital expenditures. For periods presentedbeginning January 1, 2018, we will no longer reflect integration capital expenditures within sustaining capital expenditures and will consider integrationcapital expenditures as its own component of our capital expenditures.We define integration capital expenditures as those capital expenditures made specifically with respect to recent acquisitions that are essential tointegrating acquired companies into our business.35A summary of our capital expenditures for the last three years is as follows (in thousands of dollars): Capital expenditures increased from 2016 to 2017 and were impacted by the construction of small cells and fiber (including certain constructionprojects that may take 12 to 24 months to complete) to address our customers' growing demand for data partially offset by lower amounts of improvements toexisting towers and lower sustaining capital expenditures in 2017 due to expansion of office facilities in 2016. Our sustaining capital expenditures havehistorically been less than 2% of net revenues annually and were approximately 2% of net revenues in 2017. See "Item 7. MD&A—General Overview—Outlook Highlights" for a discussion of our expectations surrounding 2018 capital expenditures.Sale of CCAL. See note 3 to our consolidated financial statements for a discussion of our sale of CCAL in May 2015.Foreign Currency Swaps. During May 2015, in conjunction with our sale of CCAL, we entered into foreign currency swaps to manage and reduceour foreign currency risk associated with the sale of CCAL. See note 9 to our consolidated financial statements.Acquisitions. Recent acquisitions consist of the acquisition of businesses such as towers and fiber. See notes 4 and 6 to our consolidated financialstatements for a discussion of our acquisitions during the years ended December 31, 2017, 2016 and 2015.Financing Activities.We seek to allocate cash generated by our operations in a manner that will enhance long-term stockholder value, which may include various financingactivities, such as (in no particular order) paying dividends on our common stock (currently expected to total at least $4.20 per share over the next 12months, or an aggregate of approximately $1.7 billion, subject to future approval by our board of directors), paying dividends on our 6.875% ConvertiblePreferred Stock (expected to total approximately $113 million over the next 12 months), purchasing our common stock, or purchasing, repaying, orredeeming our debt. See notes 8 and 12 to our consolidated financial statements.See "Item 7. MD&A—Liquidity and Capital Resources—Overview" and note 8 to our consolidated financial statements.36In 2017, our financing activities predominately related to the following:•paying an aggregate of $1.5 billion in dividends on our common stock,•issuing $500.0 million aggregate principal amount of senior unsecured notes in February 2017, the proceeds of which we used to repay a portion ofthe borrowings under the 2016 Revolver;•entering into a first amendment to the 2016 Credit Facility in February 2017 to (1) incur additional term loans in an aggregate principal amount of$500.0 million and (2) extending the maturity of both the 2016 Term Loan A and the 2016 Revolver to January 2022;•completing the May 2017 Common Stock Offering, the proceeds of which we used to partially fund the Wilcon Acquisition;•issuing the $350.0 million aggregate principal amount of senior unsecured notes in May 2017, the proceeds of which we used to (1) partially fundthe Wilcon Acquisition and (2) repay a portion of the borrowings under the 2016 Revolver;•completing the July 2017 Common Stock Offering, the proceeds of which we used to partially fund the Lightower Acquisition;•completing the 6.875% Mandatory Convertible Preferred Stock Offering, the proceeds of which we used to partially fund the Lightower Acquisition;•issuing $1.7 billion aggregate principal amount of senior unsecured notes in August 2017, the proceeds of which we used to partially fund theLightower Acquisition and pay related fees and expenses; and•entering into a second amendment to the 2016 Credit Facility in August 2017 to (1) increase the commitments under the 2016 Revolver by $1.0billion, for total commitments of $3.5 billion and (2) extend the maturity of both the 2016 Term Loan A and the 2016 Revolver to August 2022.•In addition to these 2017 financing activities, in January 2018, we issued the January 2018 Senior Notes. We used the net proceeds of the January2018 Senior Notes offering to repay (1) in full the January 2010 Tower Revenue Notes and (2) a portion of the outstanding borrowings under the2016 Revolver. See note 19 to our consolidated financial statements.In 2016, our financing activities predominately related to the following:•paying an aggregate of $1.2 billion in dividends on our common stock;•completing the 2016 Credit Facility and repaying all outstanding borrowings under our then outstanding senior secured credit facility ("2012 CreditFacility");•issuing $1.5 billion aggregate principal amount of senior unsecured notes in February 2016, the proceeds of which we used to (1) repay $500.0million of outstanding borrowings under the 2016 Revolver and (2) repay in full all outstanding borrowings under the then outstanding $1.0 billion364-Day Facility (as defined below);•issuing $1.0 billion aggregate principal amount of senior unsecured notes in May 2016, the proceeds of which we used to (1) repay in full the TowerRevenue Notes, Series 2010-2 and Series 2010-5 issued by certain of our subsidiaries and (2) repay a portion of outstanding borrowings under the2016 Revolver;•issuing $700.0 million aggregate principal amount of senior unsecured notes, the proceeds of which we used to (1) repay in full the 2.381% SecuredNotes issued by certain of our subsidiaries and (2) repay a portion of outstanding borrowings under the 2016 Revolver; and•completing the November 2016 Common Stock Offering, the proceeds of which we used to partially fund the FiberNet Acquisition.See "Item 7. MD&A—Liquidity and Capital Resources—Overview" and notes 8 and 19 to our consolidated financial statements for a discussion of ourrecent debt activities. See also "Item 7. MD&A—General Overview—Common Stock Dividend" for a discussion of the increase to our common stock dividendduring the fourth quarters of 2017 and 2016.37Incurrences, Purchases and Repayments of Debt. See notes 8 and 19 to our consolidated financial statements for a discussion of our recent issuances,purchases and repayments of debt. Our debt issuances extended the maturities of our debt portfolio, provided funding for our acquisitions and our repaymentof previously existing debt, and lowered our cost of debt. See "Item 7. MD&A—Liquidity and Capital Resources—Overview—Liquidity Position." Certain ofour communications infrastructure is held in subsidiaries whose equity interests have been pledged, directly or indirectly, along with other collateral tosecure such indebtedness. See notes 8 and 19 to our consolidated financial statements.Common Stock. As of December 31, 2017, 2016 and 2015, we had 406.3 million, 360.5 million, and 333.8 million common shares outstanding,respectively.In May 2017, we completed the May 2017 Common Stock Offering. We utilized the net proceeds from the offering to partially fund the WilconAcquisition. In July 2017, we completed the July 2017 Common Stock Offering. We utilized the net proceeds from the offering to partially fund theLightower Acquisition.In November 2016, we completed the November 2016 Common Stock Offering. We utilized the net proceeds from the offering to partially fund theFiberNet Acquisition in January 2017.During the year ended December 31, 2017, we paid an aggregate of $1.5 billion in dividends on our common stock. See "Item 1A. Risk Factors" for adescriptions of our limitations by our debt instruments and our 6.875% Mandatory Preferred Stock on our ability to pay dividends on our common stock. Seealso "Mandatory Convertible Preferred Stock," "Item 1. Business—Strategy" and note 12 to our consolidated financial statements.ATM Program. We maintain an ATM Program through which we may, from time to time, issue and sell shares of our common stock having anaggregate cumulative gross sales price of up to $500.0 million to or through sales agents. Sales, if any, under the ATM Program may be made by means ofordinary brokers' transactions on the NYSE or otherwise at market prices prevailing at the time of sale, at prices related to prevailing market prices or, subjectto our specific instructions, at negotiated prices. We intend to use the net proceeds from any sales under the ATM Program for general corporate purposes,which may include the funding of future acquisitions or investments and the repayment or repurchase of any outstanding indebtedness. During the yearended December 31, 2017, 0.2 million shares of our common stock were sold under the ATM Program, generating net proceeds of $22.0 million after givingeffect to sales commissions of $0.2 million. During the year ended December 31, 2016, 3.8 million shares of our common stock were sold under the ATMProgram generating net proceeds of $323.8 million, which we used, in part, to fund the TDC Acquisition.As of February 21, 2018, we had approximately $150 million of gross sales of common stock availability remaining on our ATM Program. See note 12to our consolidated financial statements.Mandatory Convertible Preferred Stock. In July 2017, we issued 1.65 million shares of 6.875% Convertible Preferred Stock and utilized theproceeds to partially fund the Lightower Acquisition. Unless converted earlier, each outstanding share of the 6.875% Convertible Preferred Stock willautomatically convert on August 1, 2020 into between 8.6806 and 10.4167 shares of our common stock, depending on the applicable market value of thecommon stock and subject to certain anti-dilution adjustments. At any time prior to August 1, 2020, holders of the 6.875% Convertible Preferred Stock mayelect to convert all or a portion of their shares into our common stock at the minimum conversion rate of 8.6806, subject to certain anti-dilution adjustmentsDuring October and November 2016, our approximately 9.8 million shares of 4.50% Convertible Preferred Stock converted to approximately 11.6million shares of our common stock at a conversion rate (based on the applicable market value of the common stock and subject to certain anti-dilutiveadjustments) of 1.188 common shares for each share of then outstanding 4.50% Convertible Preferred Stock.See note 12 to our consolidated financial statements for further discussion of the 6.875% Convertible Preferred Stock dividends declared and paidduring 2017 and the October and November 2016 conversion of the 4.50% Convertible Preferred Stock to common stock.Credit Facility. In January 2016, we completed the 2016 Credit Facility, consisting of (1) a $2.5 billion 2016 Revolver maturing on January 21,2021, (2) a $1.0 billion senior unsecured 364-Day revolving credit facility ("364-Day Facility") maturing in January 2017, and (3) a $2.0 billion SeniorUnsecured Term Loan A Facility ("2016 Term Loan A") maturing in January 2021. In February 2016, the 364-Day Facility was terminated. See note 8 to ourconsolidated financial statements.The 2016 Credit Facility bears interest at a per annum rate equal to LIBOR plus 1.125% to 2.000%, based on our senior unsecured debt rating. Theproceeds of the initial borrowings under the 2016 Credit Facility, together with cash on hand, were used to repay all outstanding borrowings under the 2012Credit Facility. 38The 2016 Revolver may be used for general corporate purposes, which may include the financing of capital expenditures, acquisitions and purchases ofour common stock. See notes 4 and 8 to our consolidated financial statements.In February 2017, we entered into a first amendment to the 2016 Credit Facility to (1) incur additional term loans in an aggregate principal amount of$500.0 million and (2) extend the maturity of both the 2016 Term Loan A and the 2016 Revolver to January 2022. During August 2017, we entered into asecond amendment to the 2016 Credit Facility to (1) increase the commitments under the 2016 Revolver by $1.0 billion, for total commitments of $3.5billion and (2) extend the maturity of both the 2016 Term Loan A and the 2016 Revolver to August 2022.As of February 21, 2018, there was approximately $3.0 billion in availability under the 2016 Revolver.Restricted Cash. Pursuant to the indentures governing certain of our operating companies' debt securities, all rental cash receipts of the issuers ofthese debt instruments and their subsidiaries are restricted and held by an indenture trustee. The restricted cash in excess of required reserve balances issubsequently released to us in accordance with the terms of the indentures. See also note 2 to our consolidated financial statements.Contractual Cash ObligationsThe following table summarizes our contractual cash obligations as of December 31, 2017, after giving effect to our January 2018 Senior Notes offeringand application of the net proceeds therefrom. These contractual cash obligations relate primarily to our outstanding borrowings or lease obligations for landinterests under our towers. The debt maturities reflect contractual maturity dates and do not consider the impact of the principal payments that will commencefollowing the anticipated repayment dates on the tower revenue notes (see footnote (b)). Years Ending December 31,Contractual Obligations(a)20182019202020212022 Thereafter Totals (In thousands of dollars)Debt and other long-term obligations(b)$116,045 $167,458 $155,051 $1,824,568 $3,291,737 $10,796,901 $16,351,760Interest payments on debt and other long-term obligations(c)(d)602,290 633,869 646,655 657,540 579,175 4,753,508 7,873,037Lease obligations(e)635,321 632,775 622,587 617,951 609,796 7,941,187 11,059,617Access agreement obligations(f)46,789 42,107 34,753 30,270 29,553 430,769 614,241Total contractual obligations$1,400,445 $1,476,209 $1,459,046 $3,130,329 $4,510,261 $23,922,365 $35,898,655 (a)The following items are in addition to the obligations disclosed in the above table:•We have a legal obligation to perform certain asset retirement activities, including requirements upon lease and easement terminations to remove communicationsinfrastructure or remediate the land upon which our communications infrastructure resides. The cash obligations disclosed in the above table, as of December 31, 2017, areexclusive of estimated undiscounted future cash outlays for asset retirement obligations of approximately $1.2 billion. As of December 31, 2017, the net present value ofthese asset retirement obligations was approximately $173.7 million. See note 7 to our consolidated financial statements.•We are contractually obligated to pay or reimburse others for property taxes related to our communications infrastructure.•We have the option to purchase approximately 53% of our towers that are leased or subleased or operated and managed under master leases, subleases and other agreementswith AT&T, Sprint and T-Mobile at the end of their respective lease terms. We have no obligation to exercise such purchase options. See note 1 to our consolidated financialstatements.•We have legal obligations for open purchase order commitments obtained in the ordinary course of business that have not yet been fulfilled.(b)The impact of principal payments that will commence following the anticipated repayment dates of our tower revenue notes are not considered. The tower revenue notes haveprincipal amounts of $1.0 billion, $300.0 million and $700.0 million, with anticipated repayment dates in 2020, 2022 and 2025, respectively. See notes 8 and 19 to ourconsolidated financial statements.(c)If the tower revenue notes are not repaid in full by the applicable anticipated repayment dates, the applicable interest rate increases by approximately 5% per annum and monthlyprincipal payments commence using the Excess Cash Flow (as defined in the indenture governing the applicable tower revenue notes) of the issuers of the tower revenue notes.The tower revenue notes are presented based on their contractual maturity dates ranging from 2040 to 2045 and include the impact of an assumed 5% increase in interest rate thatwould occur following the anticipated repayment dates but exclude the impact of monthly principal payments that would commence using Excess Cash Flow (as defined in theindenture governing the applicable tower revenue notes) of the issuers of the tower revenue notes. The full year 2017 Excess Cash Flow (as defined in the indenture governingthe applicable tower revenue notes) of the issuers of the tower revenue notes was approximately $599.8 million. We currently expect to refinance these notes on or prior to therespective anticipated repayment dates.(d)Interest payments on the floating rate debt are based on estimated rates currently in effect.(e)Amounts relate primarily to lease obligations for the land interests on which our towers reside and are based on the assumption that payments will be made for certain renewalperiods at our option up to the estimated communications infrastructure useful life of 20 years and an estimate of contingent payments based on revenues and gross marginsderived from existing tenant leases. See table below summarizing remaining terms to expiration.(f)Amounts relate primarily to access agreement obligations for rights-of-way, franchise pole attachments and other agreements to operate our fiber assets and are based on theassumption that payments will be made for certain renewal periods at our option up to the estimated communications infrastructure useful life of 20 years and an estimate ofcontingent payments based on revenues and gross margins derived from existing tenant contracts.39The following chart summarizes our rights to the land interests under our towers, including renewal terms at our option, as of December 31, 2017. As ofDecember 31, 2017, the leases for land interests under our towers had an average remaining life in excess of 30 years, weighted based on Towers site rentalgross margin. See "Item 1A. Risk Factors." (a)Inclusive of fee interests and perpetual easements.(b)For the year ended December 31, 2017, without consideration of the term of the tenant contract.Debt CovenantsThe credit agreement governing the 2016 Credit Facility contains financial maintenance covenants. We are currently in compliance with these financialmaintenance covenants and, based upon our current expectations, we believe we will continue to comply with these financial maintenance covenants. Inaddition, certain of our debt agreements also contain restrictive covenants that place restrictions on us and may limit our ability to, among other things, incuradditional debt and liens, purchase our securities, make capital expenditures, dispose of assets, undertake transactions with affiliates, make other investments,pay dividends or distribute excess cash flow. See note 8 to our consolidated financial statements for further discussion of our debt covenants. See "Item 1A.Risk Factors." The following are ratios applicable to the financial maintenance covenants under the credit agreement governing our 2016 Credit Facility asof December 31, 2017.Borrower / IssuerFinancial Maintenance Covenant(a)(b)Covenant LevelRequirementAs of December 31, 2017CCICTotal Net Leverage Ratio≤ 6.50x5.5xCCICTotal Senior Secured Leverage Ratio≤ 3.50x1.5xCCICConsolidated Interest Coverage Ratio(c)N/AN/A (a)Failure to comply with the financial maintenance covenants would, absent a waiver, result in an event of default under the credit agreement governing our 2016 Credit Facility.(b)As defined in the credit agreement governing our 2016 Credit Facility.(c)Applicable solely to the extent that the senior unsecured debt rating by any two of S&P, Moody's and Fitch is lower than BBB-, Baa3 or BBB-, respectively. If applicable, theconsolidated interest coverage ratio must be greater than or equal to 2.50.40Off-balance Sheet ArrangementsWe have no off-balance sheet arrangements as defined in Item 303(a)(4)(ii) of Regulation S-K.Accounting and Reporting MattersCritical Accounting Policies and EstimatesThe following is a discussion of the accounting policies and estimates that we believe (1) are most important to the portrayal of our financial conditionand results of operations or (2) require our most difficult, subjective or complex judgments, often as a result of the need to make estimates about the effect ofmatters that are inherently uncertain. The critical accounting policies and estimates for 2017 are not intended to be a comprehensive list of our accountingpolicies and estimates. See note 2 to our consolidated financial statements for a summary of our significant accounting policies. In many cases, theaccounting treatment of a particular transaction is specifically prescribed by GAAP. In other cases, management is required to exercise judgment in theapplication of accounting principles with respect to particular transactions.Revenue Recognition. 84% of our total revenue for 2017 consists of site rental revenues, which are recognized on a monthly basis over the fixed, non-cancelable term of the relevant contract (generally ranging from five to 15 years for site rental revenues derived from wireless customers and three to 20 yearsfor site rental revenues derived from our fiber solutions business), regardless of whether the payments from the tenant are received in equal monthly amounts.If the payment terms call for fixed escalations (as in fixed dollar or fixed percentage increases), upfront payments or rent free periods, the revenue isrecognized on a straight-line basis over the fixed, non-cancelable term of the contract. When calculating our straight-line rental revenues, we consider allfixed elements of tenant contractual escalation provisions, even if such escalation provisions contain a variable element (such as an escalator tied to aninflation-based index) in addition to a minimum. To the extent we acquire below-market tenant leases for contractual interests with tenants on the acquiredcommunications infrastructure (for example with respect to small cells and fiber), we record the fair value as deferred credits and amortize such deferredcredits to site rental revenues over their estimated lease term. Since we recognize revenue on a straight-line basis, a portion of the site rental revenue in agiven period represents cash collected or contractually collectible in other periods. Our assets related to straight-line site rental revenues are included in"other current assets" and "deferred site rental receivables." Amounts billed or received prior to being earned are deferred and reflected in "deferred revenues"and "other long-term liabilities." See notes 2 and 7 to our consolidated financial statements.As part of our effort to provide comprehensive communications infrastructure solutions, we also offer certain network services primarily relating to ourtowers and small cells, which represent approximately 16% of our total revenues for 2017. Network services and other revenue consists of (1) sitedevelopment services and (2) installation services. Network services revenues are recognized after completion of the applicable service. We account fornetwork services separately from the customer's site rental. See "Item 1. Business—The Company" for a further discussion of our business.Accounting for Acquisitions — General. As described in "Item 1. Business," the majority of our communications infrastructure has been acquireddirectly or indirectly from the four largest wireless carriers (or their predecessors) through transactions consummated since 1999. We evaluate each of ouracquisitions to determine if it should be accounted for as a business combination or as an acquisition of assets. For our business combinations, we allocate thepurchase price to the assets acquired and liabilities assumed based on their estimated fair value at the date of acquisition. Any purchase price in excess of thenet fair value of the assets acquired and liabilities assumed is allocated to goodwill. See "Item 7. MD&A—Accounting and Reporting Matters—Accountingfor Acquisitions—Valuation" below and note 2 to our consolidated financial statements.The determination of the final purchase price allocation could extend over several quarters resulting in the use of preliminary estimates that are subjectto adjustment until finalized. Such changes could have a significant impact on our financial statements.Accounting for Acquisitions — Leases. With respect to business combinations that include towers that we lease and operate, such as the AT&T, T-Mobile and Sprint leased and subleased towers, we evaluate such agreements to determine treatment as capital or operating leases. The evaluation of suchagreements for capital or operating lease treatment includes consideration of each of the lease classification criteria under ASC 840-10-25, namely (1) thetransfer of ownership provisions, (2) the existence of bargain purchase options, (3) the length of the remaining lease term, and (4) the present value of theminimum lease payments. With respect to the AT&T Acquisition, T-Mobile Acquisition, and the Sprint towers acquired in the Global Signal Acquisition, wedetermined that the tower leases were capital leases and the underlying land leases were operating leases based upon the lease term criterion, after consideringthe fragmentation criteria applicable under ASC 840-10-25 to leases involving both land and buildings (i.e., towers). We determined that the fragmentationcriteria was met, and the tower leases could be accounted for as capital leases apart from the land leases, which are accounted for as operating leases, since (1)the fair value of the land in the aforementioned business combinations was greater than 25% of the total fair value of the leased property at inception and (2)the tower lease expirations occur beyond 75% of the estimated economic life of the tower assets.41Accounting for Acquisitions — Valuation. As of December 31, 2017, our largest asset was property and equipment, which primarily consists ofcommunications infrastructure, followed by goodwill and intangible assets. Our identifiable intangible assets predominately relate to the site rental contractsand customer relationships intangible assets. See note 2 to our consolidated financial statements for further information regarding the nature and compositionof the site rental contracts and customer relationships intangible assets.The fair value of the vast majority of our assets and liabilities is determined by using either:(1)estimates of replacement costs (for tangible fixed assets such as towers) or(2)discounted cash flow valuation methods (for estimating identifiable intangibles such as site rental contracts and customer relationships andabove-market and below-market leases).The purchase price allocation requires subjective estimates that, if incorrectly estimated, could be material to our consolidated financial statements,including the amount of depreciation, amortization and accretion expense. The most important estimates for measurement of tangible fixed assets are (1) thecost to replace the asset with a new asset and (2) the economic useful life after giving effect to age, quality, and condition. The most important estimates formeasurement of intangible assets are (1) discount rates and (2) timing and amount of cash flows including estimates regarding customer renewals andcancellations. The most important estimates for measurement of above and below-market leases is the determination of (1) favorability or unfavorability tothe current market terms and (2) applicable lease term, including whether renewals or extensions should be measured. With respect to business combinationsthat include towers that we lease and operate, such as the T-Mobile, Sprint and AT&T leased and subleased towers, we evaluate such agreements to determinetreatment as capital or operating leases and identification of any bargain purchase options.We record the fair value of obligations to perform certain asset retirement activities, including requirements, pursuant to our ground lease, easements,and leased facility agreements to remove communications infrastructure or remediate the space upon which our communications infrastructure resides. Indetermining the fair value of these asset retirement obligations we must make several subjective and highly judgmental estimates such as those related to:(1) timing of cash flows; (2) future costs; (3) discount rates; and (4) the probability of enforcement to remove the towers or small cells or remediate the land.See note 2 to our consolidated financial statements.Accounting for Long-Lived Assets — Useful Lives. We are required to make subjective assessments as to the useful lives of our tangible and intangibleassets for purposes of determining depreciation, amortization and accretion expense that, if incorrectly estimated, could be material to our consolidatedfinancial statements. Depreciation expense for our property and equipment is computed using the straight-line method over the estimated useful lives of ourvarious classes of tangible assets. The substantial portion of our property and equipment represents the cost of our communications infrastructure, which isdepreciated with an estimated useful life equal to the shorter of (1) 20 years or (2) the term of the lease (including optional renewals) for the land interestsunder the communications infrastructure.The useful life of our intangible assets is estimated based on the period over which the intangible asset is expected to benefit us and gives considerationto the expected useful life of other assets to which the useful life may relate. We review the expected useful lives of our intangible assets on an ongoing basisand adjust if necessary. Amortization expense for intangible assets is computed using the straight-line method over the estimated useful life of each of theintangible assets. The useful life of the site rental contracts and customer relationships intangible assets is limited by the maximum depreciable life of thecommunications infrastructure (20 years), as a result of the interdependency of the communications infrastructure and site rental contracts and customerrelationships. In contrast, the site rental contracts and customer relationships are estimated to provide economic benefits for several decades because of thelow rate of tenant cancellations and high rate of renewals experienced to date. Thus, while site rental contracts and customer relationships are valued basedupon the fair value of the site rental contracts and customer relationships which includes assumptions regarding both (1) tenants' exercise of optionalrenewals contained in the acquired leases and (2) renewals of the acquired leases past the contractual term including exercisable options, the site rentalcontracts are amortized over a period not to exceed 20 years as a result of the useful life being limited by the depreciable life of the communicationsinfrastructure.Accounting for Long-Lived Assets — Impairment Evaluation. We review the carrying values of property and equipment, intangible assets, or other long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amounts may not be recoverable. We utilize the followingdual grouping policy for purposes of determining the unit of account for testing impairment of the site rental contracts and customer relationships:(1)we pool site rental contracts and customer relationships intangible assets and property and equipment into portfolio groups; and42(2)we separately pool site rental contracts and customer relationships by significant tenant or by tenant grouping for individually insignificanttenants, as appropriate.We first pool site rental contracts and customer relationships intangible assets and property and equipment into portfolio groups for purposes ofdetermining the unit of account for impairment testing, because we view communications infrastructure as portfolios and communications infrastructure in agiven portfolio and its related tenant contracts are not largely independent of the other communications infrastructure in the portfolio. We re-evaluate theappropriateness of the pooled groups at least annually. This use of grouping is based in part on (1) our limitations regarding disposal of communicationsinfrastructure, (2) the interdependencies of communications infrastructure portfolios, and (3) the manner in which communications infrastructure is traded inthe marketplace. The vast majority of our site rental contracts and customer relationships intangible assets and property and equipment are pooled into theU.S. owned communications infrastructure group. Secondly, and separately, we pool site rental contracts and customer relationships by significant tenant orby tenant grouping for individually insignificant tenants, as appropriate, for purposes of determining the unit of account for impairment testing because weassociate the value ascribed to site rental contracts and customer relationships intangible assets to the underlying contracts and related customer relationshipsacquired.Our determination that an adverse event or change in circumstance has occurred that indicates that the carrying amounts may not be recoverable willgenerally involve (1) a deterioration in an asset's financial performance compared to historical results, (2) a shortfall in an asset's financial performancecompared to forecasted results, or (3) changes affecting the utility and estimated future demands for the asset. When considering the utility of our assets, weconsider events that would meaningfully impact (1) our communications infrastructure or (2) our customer relationships. For example, consideration wouldbe given to events that impact (1) the structural integrity and longevity of our communications infrastructure or (2) our ability to derive benefit from ourexisting customer relationships, including events such as tenant's bankruptcy or insolvency or loss of a significant customer. During 2017, there were noevents or circumstances that caused us to review the carrying value of our intangible assets or property and equipment due in part to our assets performingconsistently with or better than our expectations.If the sum of the estimated future cash flows (undiscounted) from an asset, or portfolio group, significant tenant or tenant group (for individuallyinsignificant tenants), as applicable, is less than its carrying amount, an impairment loss may be recognized. If the carrying value were to exceed theundiscounted cash flows, measurement of an impairment loss would be based on the fair value of the asset, which is based on an estimate of discounted futurecash flows. The most important estimates for such calculations of undiscounted cash flows are (1) the expected additions of new tenants and equipment onour communications infrastructure and (2) estimates regarding tenant cancellations and renewals of contracts. We could record impairments in the future ifchanges in long-term market conditions, expected future operating results or the utility of the assets results in changes for our impairment test calculationswhich negatively impact the fair value of our property and equipment and intangible assets, or if we changed our unit of account in the future.Approximately 3% of our total towers currently have no tenants. We continue to pay operating expenses on these towers in anticipation of obtainingtenants on these towers in the future, primarily because of the individual tower site demographics. We estimate, based on current visibility, potential tenantson approximately half of these towers. To the extent we do not believe there are long-term prospects of obtaining tenants on an individual asset and all otherpossible avenues for recovering the carrying value has been exhausted, including sale of the asset, we appropriately reduce the carrying value of such assetsto fair value.Accounting for Goodwill — Impairment Evaluation. We test goodwill for impairment on an annual basis, regardless of whether adverse events orchanges in circumstances have occurred. The annual test begins with goodwill and all intangible assets being allocated to applicable reporting units. Wethen perform a qualitative assessment to determine whether it is "more likely than not" that the fair value of the reporting unit is less than its carrying amount.If we conclude that it is "more likely than not" that the fair value of a reporting unit is less than its carrying amount, we would be required to perform the two-step goodwill impairment test. Otherwise, the two-step goodwill impairment test is not required. Our reporting units are the same as our operating segments(Towers and Fiber). See note 16. We performed our most recent annual goodwill impairment test as of October 1, 2017, which resulted in no impairments.This assessment included consideration of our market capitalization, which was approximately four times the aggregate carrying amount of the reportingunits as of December 31, 2017.Deferred Income Taxes. We operate as a REIT for U.S. federal income tax purposes. Our REIT taxable income is generally not subject to federal andstate income taxes as a result of the deduction for dividends paid and any usage of our remaining NOLs. Accordingly, the only provision or benefit forfederal income taxes for the year ended December 31, 2017 relates to TRSs. Furthermore, as a result of the deduction for dividends paid, some or all of ourNOLs related to our REIT may expire without utilization. See "Item 1. Business—Company Developments, REIT Status and Industry Update—REIT Status"for a discussion of the impact of our REIT status. 43Our TRSs will continue to be subject, as applicable, to federal and state income taxes and foreign taxes in the jurisdictions in which such assets andoperations are located. Our ability to utilize our NOLs is dependent, in part, upon us having sufficient future earnings to utilize our NOLs before they expire.If market conditions change materially and we determine that we will be unable to generate sufficient taxable income in the future to utilize our NOLs, wewould be required to record an additional valuation allowance, which would reduce our earnings. Such adjustments could cause a material effect on ourresults of operations for the period of the adjustment. The change in our valuation allowance has no effect on our cash flows. For a further discussion of ourbenefit (provision) for income taxes, see "Item 7. MD&A—Results of Operations" and note 11 to our consolidated financial statements.Accounting PronouncementsRecently Adopted Accounting Pronouncements. See note 2 to our consolidated financial statements.Recent Accounting Pronouncements Not Yet Adopted. See note 2 to our consolidated financial statements.Non-GAAP and Segment Financial MeasuresIn addition to the non-GAAP measures used herein and as discussed in note 16 to our consolidated financial statements, we also provide (1) segmentsite rental gross margin, (2) segment network services and other gross margin, and (3) segment operating profit, which are key measures used by managementto evaluate our operating segments for purposes of making decisions about allocating capital and assessing performance. These segment measures areprovided pursuant to GAAP requirements related to segment reporting.We define segment site rental gross margin as segment site rental revenues less segment site rental cost of operations, which excludes stock-basedcompensation expense and prepaid lease purchase price adjustments recorded in consolidated site rental cost of operations. We define segment networkservices and other gross margin as segment network services and other revenues less segment network services and other cost of operations, which excludesstock-based compensation expense recorded in consolidated network services and other cost of operations. We define segment operating profit as segmentrevenues less segment cost of operations and segment general and administrative expenses, excluding stock-based compensation (recorded in cost ofoperations and general and administrative expenses) and prepaid purchase price adjustments (recorded in cost of operations).We use earnings before interest, taxes, depreciation, amortization, and accretion, as adjusted ("Adjusted EBITDA"), which is a non-GAAP financialmeasure, as an indicator of consolidated financial performance. Our measure of Adjusted EBITDA may not be comparable to similarly titled measures of othercompanies, including companies in the communications infrastructure sector or other REITs, and is not a measure of performance calculated in accordancewith GAAP. Adjusted EBITDA should not be considered in isolation or as a substitute for operating income (loss), net income (loss), net cash provided by(used for) operating, investing and financing activities or other income statement or cash flow statement data prepared in accordance with GAAP and shouldbe considered only as a supplement to net income (loss) computed in accordance with GAAP as a measure of our performance. There are material limitationsto using a measure such as Adjusted EBITDA, including the difficulty associated with comparing results among more than one company, including ourcompetitors, and the inability to analyze certain significant items, including depreciation and interest expense, that directly affect our net income or loss.Management compensates for these limitations by considering the economic effect of the excluded expense items independently as well as in connectionwith their analysis of net income (loss).We define Adjusted EBITDA as net income (loss) plus restructuring charges (credits), asset write-down charges, acquisition and integration costs,depreciation, amortization and accretion, amortization of prepaid lease purchase price adjustments, interest expense and amortization of deferred financingcosts, (gains) losses on retirement of long-term obligations, net (gain) loss on interest rate swaps, (gains) losses on foreign currency swaps, impairment ofavailable-for-sale securities, interest income, other (income) expense, (benefit) provision for income taxes, cumulative effect of a change in accountingprinciple, (income) loss from discontinued operations and stock-based compensation expense. The reconciliation of Adjusted EBITDA to our net income(loss) is set forth below and excludes items in our Adjusted EBITDA definition which are not applicable to the periods shown.44 Year Ended December 31,(dollars in thousands)2017 2016 2015Net income (loss)$444,550 $356,973 $1,524,335Adjustments to increase (decrease) net income (loss): (Income) loss from discontinued operations— — (999,049)Asset write-down charges17,322 34,453 33,468Acquisition and integration costs61,431 17,453 15,678Depreciation, amortization and accretion1,242,408 1,108,551 1,036,178Amortization of prepaid lease purchase price adjustments20,120 21,312 20,531Interest expense and amortization of deferred financing costs590,682 515,032 527,128(Gains) losses on retirement of long-term obligations3,525 52,291 4,157Interest income(18,761) (796) (1,906)Other (income) expense(1,994) 8,835 (57,028)(Benefit) provision for income taxes26,043 16,881 (51,457)Stock-based compensation expense96,435 96,538 67,148Adjusted EBITDA(a)$2,481,761 $2,227,523 $2,119,183 (a)The above reconciliation excludes the items included in our Adjusted EBITDA definition which are not applicable to the periods shown.We believe Adjusted EBITDA is useful to investors or other interested parties in evaluating our financial performance because:•it is the primary measure used by our management to evaluate (1) the economic productivity of our operations and (2) for purposes of makingdecisions about allocating resources to, and assessing the performance of, our operations;•although specific definitions may vary, it is widely used by investors or other interested parties in evaluation of the communications infrastructuresector and other REITs to measure financial performance without regard to items such as depreciation, amortization and accretion which can varydepending upon accounting methods and the book value of assets;•we believe it helps investors and other interested parties meaningfully evaluate and compare the results of our operations (1) from period to periodand (2) to our competitors by removing the impact of our capital structure (primarily interest charges from our outstanding debt) and asset base(primarily depreciation, amortization and accretion) from our financial results; and•it is similar to the measure of current financial performance generally used in our debt covenant calculations.Our management uses Adjusted EBITDA:•as a performance goal in employee annual incentive compensation;•as a measurement of financial performance because it assists us in comparing our financial performance on a consistent basis as it removes theimpact of our capital structure (primarily interest charges from our outstanding debt) and asset base (primarily depreciation, amortization, andaccretion) from our operating results;•in presentations to our board of directors to enable it to have the same measurement of financial performance used by management;•for planning purposes, including preparation of our annual operating budget;•as a valuation measure in strategic analyses in connection with the purchase and sale of assets;•in determining self-imposed limits on our debt levels, including the evaluation of our leverage ratio and interest coverage ratio; and•with respect to compliance with our debt covenants, which require us to maintain certain financial ratios that incorporate concepts such as, orsimilar to, Adjusted EBITDA.Item 7A. Quantitative and Qualitative Disclosures About Market RiskOur primary exposures to market risks are related to changes in interest rates, which may adversely affect our results of operations and financial position.We seek to manage exposure to changes in interest rates where economically prudent to do so by utilizing fixed rate debt.45Our interest rate risk relates primarily to the impact of interest rate movements on the following, after giving effect to our January 2018 Senior Notesoffering and the application of the net proceeds therefrom:•the potential refinancing of our $16.2 billion in existing debt, compared to $12.2 billion in the prior year;•our $3.0 billion of floating rate debt representing approximately 18% of total debt, compared to 16% in the prior year; and•potential future borrowings of incremental debt, including borrowings under our 2016 Credit Facility.Potential Refinancing of Existing DebtWe have no debt maturities other than principal payments on amortizing debt or anticipated repayment dates over the next 12 months. As ofDecember 31, 2017 and December 31, 2016, we had no interest rate swaps hedging any refinancings. See below for a tabular presentation of our scheduledcontractual debt maturities as of December 31, 2017 and a discussion of anticipated repayment dates.Floating Rate DebtWe manage our exposure to market interest rates on our existing debt by controlling the mix of fixed and floating rate debt. As of December 31, 2017,after giving effect to our January 2018 Senior Notes offering and the application of the net proceeds therefrom, we had $3.0 billion of floating rate debt, noneof which had LIBOR floors. As a result, a hypothetical unfavorable fluctuation in market interest rates on our existing debt of 1/8 of a percent point over a 12-month period would increase our interest expense by approximately $4 million. As of December 31, 2016, we had approximately $2.0 billion of floating ratedebt, none of which had LIBOR floors.Potential Future Borrowings of Incremental DebtWe typically do not hedge our exposure to interest rates on potential future borrowings of incremental debt for a substantial period prior to issuance.See "Item 7. MD&A—Liquidity and Capital Resources" regarding our liquidity strategy.46The following table provides information about our market risk related to changes in interest rates. The future principal payments and weighted-averageinterest rates are presented as of December 31, 2017 after giving effect to our January 2018 Senior Notes offering and the application of the net proceedstherefrom (see note 19 to our consolidated financial statements). These debt maturities reflect contractual maturity dates, and do not consider the impact ofthe principal payments that will commence following the anticipated repayment dates of certain debt (see footnotes (b) and (d)). See note 8 to ourconsolidated financial statements for additional information regarding our debt. Future Principal Payments and Interest Rates by the Debt Instruments' Contractual Year of Maturity 2018 2019 2020 2021 2022 Thereafter Total Fair Value(a) (Dollars in thousands)Fixed rate debt(b)$54,482 $44,333 $31,926 $1,578,318 $874,862 $10,796,901 $13,380,822 $13,757,200Average interest rate(b)(c)(d)4.4% 4.5% 4.6% 2.9% 4.9% 5.0% 4.8% Variable rate debt(e)$61,563 $123,125 $123,125 $246,250 $2,416,875 $— $2,970,938 $2,970,938Average interest rate(e)3.2% 3.5% 3.6% 3.6% 3.7% —% 3.6% (a)The fair value of our debt is based on indicative quotes (that is, non-binding quotes) from brokers that require judgment to interpret market information, including implied creditspreads for similar borrowings on recent trades or bid/ask offers. These fair values are not necessarily indicative of the amount, which could be realized in a current marketexchange.(b)The impact of principal payments that will commence following the anticipated repayment dates is not considered. The tower revenue notes have principal amounts of $1.0billion, $300.0 million and $700.0 million, with anticipated repayment dates in 2020, 2022 and 2025, respectively.(c)The average interest rate represents the weighted-average stated coupon rate (see also footnote (d)).(d)If the tower revenue notes are not repaid in full by the applicable anticipated repayment dates, the applicable interest rate increases by approximately 5% per annum and monthlyprincipal payments commence using the Excess Cash Flow (as defined in the indenture governing the applicable tower revenue notes) of the issuers of the tower revenue notes.The tower revenue notes are presented based on their contractual maturity dates ranging from 2040 to 2045 and include the impact of an assumed 5% increase in interest rate thatwould occur following the anticipated repayment dates but exclude the impact of monthly principal payments that would commence using Excess Cash Flow of the issuers of thetower revenue notes. The full year 2017 Excess Cash Flow of the issuers of the tower revenue notes was approximately $599.8 million. We currently expect to refinance thesenotes on or prior to the respective anticipated repayment dates.(e)Predominantly consists of our 2016 Term Loan A and 2016 Revolver borrowings, each of which matures in 2022.47Item 8. Financial Statements and Supplementary DataCrown Castle International Corp. and SubsidiariesIndex to Consolidated Financial Statements and Financial Statement Schedules PageReport of Independent Registered Public Accounting Firm 49Consolidated Balance Sheet as of December 31, 2017 and 2016 51Consolidated Statement of Operations and Comprehensive Income (Loss) for each of the three years in the period ended December 31, 2017 52Consolidated Statement of Cash Flows for each of the three years in the period ended December 31, 2017 53Consolidated Statement of Equity for each of the three years in the period ended December 31, 2017 54Notes to Consolidated Financial Statements 57Schedule II - Valuation and Qualifying Accounts for the years ended December 31, 2017, 2016 and 2015 102Schedule III - Schedule of Real Estate and Accumulated Depreciation for the years ended December 31, 2017 and 2016 10348REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRMTo the Board of Directors and Stockholders ofCrown Castle International Corp.Opinions on the Financial Statements and Internal Control over Financial ReportingWe have audited the accompanying consolidated balance sheets of Crown Castle International Corp. and its subsidiaries as of December 31, 2017 and 2016,and the related consolidated statements of operations and comprehensive income (loss), of cash flows, and of equity for each of the three years in the periodended December 31, 2017, including the related notes and financial statement schedules listed in the accompanying index (collectively referred to as the"consolidated financial statements"). We also have audited the Company's internal control over financial reporting as of December 31, 2017, based on criteriaestablished in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as ofDecember 31, 2017 and 2016, and the results of their operations and their cash flows for each of the three years in the period ended December 31, 2017 inconformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all materialrespects, effective internal control over financial reporting as of December 31, 2017, based on criteria established in Internal Control - Integrated Framework(2013) issued by the COSO.Basis for OpinionsThe Company's management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, andfor its assessment of the effectiveness of internal control over financial reporting, included in Management's Report on Internal Control over FinancialReporting appearing under Item 9A. Our responsibility is to express opinions on the Company's consolidated financial statements and on the Company'sinternal control over financial reporting based on our audits. We are a public accounting firm registered with the Public Company Accounting OversightBoard (United States) ("PCAOB") and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and theapplicable rules and regulations of the Securities and Exchange Commission and the PCAOB.We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonableassurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internalcontrol over financial reporting was maintained in all material respects.Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financialstatements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis,evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles usedand significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. Our audit of internalcontrol over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weaknessexists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performingsuch other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.As described in Management’s Report on Internal Control over Financial Reporting, management has excluded FiberNet, Wilcon, and Lightower from itsassessment of internal control over financial reporting as of December 31, 2017, because they were acquired by the Company in purchase businesscombinations during 2017. We have also excluded FiberNet, Wilcon, and Lightower from our audit of internal control over financial reporting. FiberNet,Wilcon, and Lightower are wholly-owned subsidiaries whose total assets and total revenues excluded from management’s assessment and our audit ofinternal control over financial reporting collectively represent approximately $3.1 billion and $314 million, respectively, of the related consolidatedfinancial statement amounts as of and for the year ended December 31, 2017.Definition and Limitations of Internal Control over Financial ReportingA company's internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reportingand the preparation of financial statements for external purposes in accordance with generally accepted49accounting principles. A company's internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance ofrecords that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurancethat transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and thatreceipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and(iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company's assets that couldhave a material effect on the financial statements.Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation ofeffectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliancewith the policies or procedures may deteriorate./s/ PricewaterhouseCoopers LLPPittsburgh, PennsylvaniaFebruary 26, 2018We have served as the Company's auditor since 2011.50CROWN CASTLE INTERNATIONAL CORP. AND SUBSIDIARIESCONSOLIDATED BALANCE SHEET(In thousands of dollars, except share amounts) December 31, 2017 2016ASSETS Current assets: Cash and cash equivalents$314,094 $567,599Restricted cash121,065 124,547Receivables, net of allowance of $13,746 and $11,314, respectively397,585 373,532Prepaid expenses162,366 128,721Other current assets138,670 130,362Total current assets1,133,780 1,324,761Deferred site rental receivables1,300,338 1,317,658Property and equipment, net12,932,885 9,805,315Goodwill10,021,468 5,757,676Site rental contracts and customer relationships, net5,626,435 3,298,778Other intangible assets, net335,324 351,294Long-term prepaid rent and other assets, net879,340 819,610Total assets$32,229,570 $22,675,092LIABILITIES AND EQUITY Current liabilities: Accounts payable$248,817 $188,516Accrued interest131,790 97,019Deferred revenues457,116 353,005Other accrued liabilities339,108 221,066Current maturities of debt and other obligations115,251 101,749Total current liabilities1,292,082 961,355Debt and other long-term obligations16,044,369 12,069,393Other long-term liabilities2,554,037 2,087,229Total liabilities19,890,488 15,117,977Commitments and contingencies (see note 14) CCIC stockholders' equity: Common stock, $0.01 par value; 600,000,000 shares authorized; shares issued and outstanding: December 31, 2017—406,280,673 and December 31, 2016—360,536,6594,063 3,6056.875% Mandatory Convertible Preferred Stock, Series A, $0.01 par value; 20,000,000 shares authorized; shares issuedand outstanding: December 31, 2017—1,649,998 and December 31, 2016—0; aggregate liquidation value: December31, 2017—$1,649,998 and December 31, 2016—$017 —Additional paid-in capital16,843,607 10,938,236Accumulated other comprehensive income (loss)(3,989) (5,888)Dividends/distributions in excess of earnings(4,504,616) (3,378,838)Total equity12,339,082 7,557,115Total liabilities and equity$32,229,570 $22,675,092See accompanying notes to consolidated financial statements.51CROWN CASTLE INTERNATIONAL CORP. AND SUBSIDIARIESCONSOLIDATED STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS)(In thousands of dollars, except per share amounts) Years Ended December 31, 2017 2016 2015Net revenues: Site rental$3,669,191 $3,233,307 $3,018,413Network services and other686,414 687,918 645,438Net revenues4,355,605 3,921,225 3,663,851Operating expenses: Costs of operations(a): Site rental1,143,914 1,023,350 963,869Network services and other419,787 417,171 357,557General and administrative426,698 371,031 310,921Asset write-down charges17,322 34,453 33,468Acquisition and integration costs61,431 17,453 15,678Depreciation, amortization and accretion1,242,408 1,108,551 1,036,178Total operating expenses3,311,560 2,972,009 2,717,671Operating income (loss)1,044,045 949,216 946,180Interest expense and amortization of deferred financing costs(590,682) (515,032) (527,128)Gains (losses) on retirement of long-term obligations(3,525) (52,291) (4,157)Interest income18,761 796 1,906Other income (expense)1,994 (8,835) 57,028Income (loss) from continuing operations before income taxes470,593 373,854 473,829Benefit (provision) for income taxes(26,043) (16,881) 51,457Income (loss) from continuing operations444,550 356,973 525,286Discontinued operations (see note 3): Income (loss) from discontinued operations, net of tax— — 19,690Net gain (loss) from disposal of discontinued operations, net of tax— — 979,359Income (loss) from discontinued operations, net of tax— — 999,049Net income (loss)444,550 356,973 1,524,335Less: Net income (loss) attributable to the noncontrolling interest— — 3,343Net income (loss) attributable to CCIC stockholders444,550 356,973 1,520,992Dividends on preferred stock(58,294) (32,991) (43,988)Net income (loss) attributable to CCIC common stockholders$386,256 $323,982 $1,477,004Net income (loss)$444,550 $356,973 $1,524,335Other comprehensive income (loss): Interest rate swaps reclassified into results of operations, net of taxes— — 18,725Foreign currency translation adjustments1,899 (1,490) (14,137)Amounts reclassified into discontinued operations for foreign currency translation adjustments (see note3)— — (25,678)Total other comprehensive income (loss)1,899 (1,490) (21,090)Comprehensive income (loss) attributable to CCIC stockholders$446,449 $355,483 $1,503,245Net income (loss) attributable to CCIC common stockholders, per common share: Income (loss) from continuing operations, basic$1.01 $0.95 $1.45Income (loss) from discontinued operations, basic$— $— $2.99Net income (loss) attributable to CCIC common stockholders, basic$1.01 $0.95 $4.44Income (loss) from continuing operations, diluted$1.01 $0.95 $1.44Income (loss) from discontinued operations, diluted$— $— $2.98Net income (loss) attributable to CCIC common stockholders, diluted$1.01 $0.95 $4.42Weighted-average common shares outstanding (in thousands): Basic381,740 340,349 333,002Diluted383,221 340,879 334,062Dividends/distributions declared per share of common stock$3.90 $3.61 $3.35 (a)Exclusive of depreciation, amortization and accretion shown separately.See accompanying notes to consolidated financial statements.52CROWN CASTLE INTERNATIONAL CORP. AND SUBSIDIARIESCONSOLIDATED STATEMENT OF CASH FLOWS(In thousands of dollars) Years Ended December 31, 201720162015 Cash flows from operating activities: Net income (loss) from continuing operations$444,550 $356,973 $525,286 Adjustments to reconcile net income (loss) to net cash provided by (used for) operating activities: Depreciation, amortization and accretion1,242,408 1,108,551 1,036,178 (Gains) losses on retirement of long-term obligations3,525 52,291 4,157 (Gains) losses on settled swaps328 2,608 (54,475) Amortization of deferred financing costs and other non-cash interest9,368 14,333 37,126 Stock-based compensation expense91,647 79,338 60,773 Asset write-down charges17,322 34,453 33,468 Deferred income tax (benefit) provision14,888 8,603 (60,618) Other non-cash adjustments, net(1,648) 2,451 (8,915) Changes in assets and liabilities, excluding the effects of acquisitions: Increase (decrease) in accrued interest34,771 30,044 32 Increase (decrease) in accounts payable(34,067) 10,600 (5,287) Increase (decrease) in deferred revenues, deferred ground lease payables, other accrued liabilitiesand other liabilities175,522 195,998 325,880 Decrease (increase) in receivables60,859 (58,664) 12,668 Decrease (increase) in prepaid expenses, deferred site rental receivables, long-term prepaid rent,restricted cash and other assets(15,287) (55,315) (112,248) Net cash provided by (used for) operating activities2,044,186 1,782,264 1,794,025 Cash flows from investing activities: Payment for acquisitions of businesses, net of cash acquired(9,260,135) (556,854) (1,102,179) Capital expenditures(1,228,071) (873,883) (908,892) Net (payments) receipts from settled swaps(328) 8,141 54,475 Other investing activities, net(5,487) 12,364 (3,138) Net cash provided by (used for) investing activities(10,494,021) (1,410,232) (1,959,734) Cash flows from financing activities: Proceeds from issuance of long-term debt3,092,323 5,201,010 1,000,000 Principal payments on debt and other long-term obligations(118,880) (95,787) (102,866) Purchases and redemptions of long-term debt— (4,044,834) (1,069,337) Payments under revolving credit facility(1,840,000) (4,565,000) (1,360,000) Borrowings under revolving credit facility2,820,000 3,440,000 1,790,000 Payments for financing costs(29,240) (41,533) (19,642) Net proceeds from issuance of common stock4,221,329 1,325,865 — Net proceeds from issuance of preferred stock1,607,759 — — Purchases of common stock(23,307) (24,936) (29,657) Dividends/distributions paid on common stock(1,508,705) (1,239,158) (1,116,444) Dividends paid on preferred stock(29,935) (43,988) (43,988) Net (increase) decrease in restricted cash3,808 (7,931) 16,458 Net cash provided by (used for) financing activities8,195,152 (96,292) (935,476) Net increase (decrease) in cash and cash equivalents - continuing operations(254,683) 275,740 (1,101,185) Discontinued operations (see note 3): Net cash provided by (used for) operating activities— — 2,700 Net cash provided by (used for) investing activities— 113,150 1,103,577 Net increase (decrease) in cash and cash equivalents - discontinued operations— 113,150 1,106,277 Effect of exchange rate changes on cash1,178 (101) (1,902) Cash and cash equivalents at beginning of year567,599178,810 175,620(a) Cash and cash equivalents at end of year$314,094 $567,599 $178,810 ________________(a)Inclusive of cash and cash equivalents included in discontinued operations.See accompanying notes to consolidated financial statements.53CROWN CASTLE INTERNATIONAL CORP. AND SUBSIDIARIESCONSOLIDATED STATEMENT OF EQUITY(In thousands of dollars, except share data) Common Stock 6.875% MandatoryConvertiblePreferred Stock 4.50% MandatoryConvertible PreferredStock Accumulated Other Comprehensive Income (Loss) ("AOCI") Shares ($0.01 Par) Shares ($0.01 Par) Shares ($0.01 Par) AdditionalPaid-InCapital ForeignCurrencyTranslationAdjustments DerivativeInstruments Total AOCI Dividends/Distributionsin Excess of Earnings Noncontrollinginterest fromdiscontinuedoperations TotalBalance, December 31,2014333,856,632 $3,339 — — 9,775,000—$98 $9,512,396 $34,545 $(18,725) $15,820 $(2,815,428) $21,003 $6,737,228Stock-basedcompensationrelated activity, netof forfeitures251,554 2 — — ——— 65,838 — — — — — 65,840Purchases andretirement ofcommon stock(336,526) (3) — — ——— (29,654) — — — — — (29,657)Other comprehensiveincome (loss)(a)— — — — ——— — (38,943) 18,725 (20,218) — (872) (21,090)Disposition of CCAL— — — — — — — — — — — (23,474) (23,474)Common stockdividends/distributions— — — — — — — — — — (1,119,973) — (1,119,973)Preferred stockdividends— — — — ——— — — — — (43,988) — (43,988)Net income (loss)— — — — ——— — — — — 1,520,992 3,343 1,524,335Balance, December 31,2015333,771,660 $3,338 — — 9,775,000$98 $9,548,580 $(4,398) $— $(4,398) $(2,458,397) $— $7,089,221 (a)See the consolidated statement of operations and comprehensive income (loss) for the components of "total other comprehensive income (loss)" and note 9 with respect to thereclassification adjustment.54CROWN CASTLE INTERNATIONAL CORP. AND SUBSIDIARIESCONSOLIDATED STATEMENT OF EQUITY(In thousands of dollars, except share data) Common Stock 6.875% MandatoryConvertiblePreferred Stock 4.50% MandatoryConvertible PreferredStock AOCI Shares ($0.01 Par) Shares ($0.01 Par) Shares ($0.01 Par) AdditionalPaid-InCapital ForeignCurrencyTranslationAdjustments DerivativeInstruments TotalAOCI Dividends/Distributionsin Excess of Earnings Noncontrollinginterest fromdiscontinuedoperations TotalBalance, December 31,2015333,771,660 $3,338 — — 9,775,000 $98 $9,548,580 $(4,398) $— $(4,398) $(2,458,397) $— $7,089,221Stock-basedcompensation relatedactivity, net offorfeitures263,782 2 — — — — 86,271 — — — — — 86,273Purchases and retirementof common stock(289,531) (3) — — — — (24,933) — — — — — (24,936)Net proceeds fromissuance of commonstock15,178,064 152 — — — — 1,325,713 — — — — — 1,325,865Other comprehensiveincome (loss)(a)— — — — — — — (1,490) — (1,490) — — (1,490)Recognition of excess taxbenefit— — — — — — 2,623 — — — — — 2,623Common stockdividends/distributions— — — — — — — — — — (1,244,423) — (1,244,423)Preferred stock dividends— — — — — — — — — — (32,991) — (32,991)Conversion of preferredstock to commonstock (see note 12)11,612,684 116 — — (9,775,000) (98) (18) — — — — — —Net income (loss)— — — — — — — — — — 356,973 — 356,973Balance, December 31,2016360,536,659 $3,605 —— — $— $10,938,236 $(5,888) $— $(5,888) $(3,378,838) $— $7,557,115 (a)See the consolidated statement of operations and comprehensive income (loss) for the components of "total other comprehensive income (loss)."See accompanying notes to consolidated financial statements.55CROWN CASTLE INTERNATIONAL CORP. AND SUBSIDIARIESCONSOLIDATED STATEMENT OF EQUITY(In thousands of dollars, except share data) Common Stock 6.875% MandatoryConvertible PreferredStock 4.50% MandatoryConvertiblePreferred Stock AOCI Shares ($0.01 Par) Shares ($0.01 Par) Shares ($0.01 Par) AdditionalPaid-InCapital ForeignCurrencyTranslationAdjustments DerivativeInstruments TotalAOCI Dividends/Distributionsin Excess of Earnings Noncontrollinginterest fromdiscontinuedoperations TotalBalance, December 31,2016360,536,659 $3,605 — — — $— $10,938,236 $(5,888) $— $(5,888) $(3,378,838) $— $7,557,115Stock-basedcompensation relatedactivity, net offorfeitures861,028 10 — — ——— 99,978 — — — — — 99,988Purchases and retirementof common stock(259,331) (3) — — ——— (23,304) — — — — — (23,307)Net proceeds fromissuances of commonstock (see note 12)45,142,300 451 — — — — 4,220,878 — — — — — 4,221,329Net proceeds fromissuances of preferredstock (see note 12)— — 1,650,000 17 — — 1,607,742 — — — — — 1,607,759Other comprehensiveincome (loss)(a)— — — — ——— — 1,899 1,899 — — 1,899Recognition of excess taxbenefit— — — — ——— 77 — — — — — 77Common stockdividends/distributions— — — — — — — — — — (1,512,034) — (1,512,034)Preferred stock dividends— — — — ——— — — — — (58,294) — (58,294)Conversion of preferredstock to common stock(see note 12)17 — (2) — — — — — — — — — —Net income (loss) ——— — — — — 444,550 — 444,550Balance, December 31,2017406,280,673 $4,063 1,649,998 17 — $— $16,843,607 $(3,989) $— $(3,989) $(4,504,616) $— $12,339,082 (a)See the consolidated statement of operations and comprehensive income (loss) for the components of "total other comprehensive income (loss)."See accompanying notes to consolidated financial statements.56NOTES TO CONSOLIDATED FINANCIAL STATEMENTS(Tabular dollars in thousands, except per share amounts)1.Basis of PresentationThe consolidated financial statements include the accounts of Crown Castle International Corp. and its predecessor, as applicable (together, "CCIC"),and their subsidiaries, collectively referred to herein as the "Company." All significant intercompany balances and transactions have been eliminated inconsolidation. As used herein, the term "including," and any variation thereof, means "including without limitation." The use of the word "or" herein is notexclusive. Unless the context suggests otherwise, references to "U.S." are to the United States of America and Puerto Rico, collectively.The Company owns, operates and leases shared communications infrastructure that is geographically dispersed throughout the U.S, including (1) towersand other structures, such as rooftops (collectively, "towers"), and (2) fiber primarily supporting small cell networks ("small cells") and fiber solutions. TheCompany's towers, fiber and small cells assets are collectively referred to herein as "communications infrastructure," and the Company's customers on itscommunications infrastructure are referred to herein as "tenants."The Company's core business is providing access, including space or capacity, to its shared communications infrastructure via long-term contracts invarious forms, including licenses, subleases and lease agreements (collectively, "contracts").Approximately 53% of the Company's towers are leased or subleased or operated and managed under master leases, subleases, or other agreements withAT&T, Sprint, and T-Mobile. The Company has the option to purchase these towers at the end of their respective lease terms. The Company has noobligation to exercise such purchase options. Additional information concerning these towers is as follows:◦Approximately 22% of the Company's towers are leased or subleased or operated and managed under a master prepaid lease or other relatedagreements with AT&T for a weighted-average initial term of approximately 28 years, weighted on site rental gross margin. The Company has theoption to purchase the leased and subleased towers from AT&T at the end of the respective lease or sublease terms for aggregate option paymentsof approximately $4.2 billion, which payments, if exercised, would be due between 2032 and 2048.◦Approximately 16% of the Company's towers are leased or subleased or operated and managed for an initial period of 32 years (through May2037) under master leases, subleases, or other agreements with Sprint. The Company has the option to purchase in 2037 all (but not less than all)of the leased and subleased Sprint towers from Sprint for approximately $2.3 billion.◦Approximately 15% of the Company's towers are leased or subleased or operated and managed under a master prepaid lease or other relatedagreements with T-Mobile for a weighted-average initial term of approximately 28 years, weighted on site rental gross margin. The Company hasthe option to purchase the leased and subleased towers from T-Mobile at the end of the respective lease or sublease terms for aggregate optionpayments of approximately $2.0 billion, which payments, if exercised would be due between 2035 and 2049. In addition, through the acquisitionof the rights to approximately 7,100 towers ("T-Mobile Acquisition"), there are another approximately 1% of the Company's towers subject to alease and sublease or other related arrangements with AT&T. The Company has the option to purchase these towers that it does not otherwisealready own at the end of their respective lease terms for aggregate option payments of up to approximately $405 million, which payments, ifexercised, would be due between 2018 and 2032 (less than $10 million would be due before 2025).As part of the Company's effort to provide comprehensive communications infrastructure solutions, the Company also offers certain network servicesrelating to its communications infrastructure, consisting of (1) site development services primarily relating to existing or new tenant equipment installationson its towers and small cells, including: site acquisition, architectural and engineering, or zoning and permitting (collectively, "site development services")and (2) tenant equipment installation or subsequent augmentations (collectively, "installation services").The Company operates as a real estate investment trust ("REIT") for U.S. federal income tax purposes. In addition, the Company has certain taxableREIT subsidiaries ("TRSs"). See note 11.The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("GAAP") requires management to makeestimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities as of the date of thefinancial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.57As a result of the 2017 Acquisitions of fiber assets as described in note 4, the Company has changed the name of the "Small Cells" operating segment to"Fiber." The Company changed the name of this segment to reflect its strategy of utilizing the same fiber assets to provide both small cells and fiber solutionsto its customers. The name change did not impact the composition or the previously-reported operating results of the Fiber segment. As such, the Company'soperating segments are now referred to as "Towers" and "Fiber." See note 16.2.Summary of Significant Accounting PoliciesRestricted CashRestricted cash represents (1) the cash held in reserve by the indenture trustees pursuant to the indenture governing certain of the Company's debtinstruments, (2) cash securing performance obligations such as letters of credit, as well as (3) any other cash whose use is limited by contractual provisions.The restriction of rental cash receipts is a critical feature of certain of the Company's debt instruments, due to the applicable indenture trustee's ability toutilize the restricted cash for the payment of (1) debt service costs, (2) ground rents, (3) real estate or personal property taxes, (4) insurance premiums relatedto towers, (5) other assessments by governmental authorities and potential environmental remediation costs, or (6) a portion of advance rents from tenants.The restricted cash in excess of required reserve balances is subsequently released to the Company in accordance with the terms of the indentures. TheCompany has classified the increases and decreases in restricted cash as (1) cash provided by financing activities for cash held by indenture trustees based onconsideration of the terms of the related indebtedness, although the cash flows have aspects of both financing activities and operating activities, (2) cashprovided by investing activities for cash securing performance obligations and restricted cash that is acquired in acquisitions, or (3) cash provided byoperating activities for the other remaining restricted cash.The following table is a summary of the impact of restricted cash on the statement of cash flows. For the years ended December 31, 201720162015Net cash provided by (used from) operating activities$847 $(4,547) $3,974Net cash provided by (used from) investing activities$(26) $10,541 $(3,752)Net cash provided by (used from) financing activities$3,808 $(7,931) $16,458Receivables AllowanceAn allowance for doubtful accounts is recorded as an offset to accounts receivable. The Company uses judgment in estimating this allowance andconsiders historical collections, current credit status, or contractual provisions. Additions to the allowance for doubtful accounts are charged either to "siterental costs of operations" or to "network services and other costs of operations," as appropriate; and deductions from the allowance are recorded whenspecific accounts receivable are written off as uncollectible.Lease AccountingGeneral. The Company classifies its leases at inception as either operating leases or capital leases. A lease is classified as a capital lease if at least one ofthe following criteria is met, subject to certain exceptions noted below: (1) the lease transfers ownership of the leased assets to the lessee, (2) there is a bargainpurchase option, (3) the lease term is equal to 75% or more of the economic life of the leased assets, or (4) the present value of the minimum lease paymentsequals or exceeds 90% of the fair value of the leased assets.Lessee. Leases for land are evaluated for capital lease treatment if at least one of the first two criteria mentioned in the immediately preceding paragraphis present relating to the leased assets. When the Company, as lessee, classifies a lease as a capital lease, it records an asset in an amount equal to the presentvalue of the minimum lease payments under the lease at the beginning of the lease term. Applicable operating leases are recognized on a straight-line basis asdiscussed under "costs of operations" below.Lessor. If the Company is the lessor of leased property that is part of a larger whole (including a portion of space on a tower) and for which fair value isnot objectively determinable, then such a lease is accounted for as an operating lease. As applicable, operating leases are recognized on a straight-line basisas discussed under "Revenue Recognition."See also "Recent Accounting Pronouncements Not Yet Adopted" below for further discussion.58NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Property and EquipmentProperty and equipment is stated at cost, net of accumulated depreciation. Property and equipment includes land owned in fee and perpetual easementsfor land, which have no definite life. When the Company purchases fee ownership or perpetual easements for the land previously subject to ground lease, theCompany reduces the value recorded as land by the amount of any associated deferred ground lease payable or unamortized above-market leases.Depreciation is computed utilizing the straight-line method at rates based upon the estimated useful lives of the various classes of assets. Depreciation ofcommunications infrastructure is computed with a useful life equal to the shorter of 20 years or the term of the underlying ground lease (including optionalrenewal periods). Additions, renewals, and improvements are capitalized, while maintenance and repairs are expensed. Labor and interest costs incurreddirectly related to the construction of certain property and equipment are capitalized during the construction phase of projects. For the years ended December31, 2017, 2016, and 2015, the Company had $91.9 million, $86.1 million, and $36.7 million in capitalized labor costs, respectively. The carrying value ofproperty and equipment is reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not berecoverable.Abandonments and write-offs of property and equipment are recorded to "asset write-down charges" on the Company's consolidated statement ofoperations and comprehensive income (loss) and were $14.3 million, $26.9 million, and $27.0 million for the years ended December 31, 2017, 2016, and2015, respectively.Asset Retirement ObligationsPursuant to its ground lease, easement and leased facility agreements, the Company records obligations to perform asset retirement activities, includingrequirements to remove communications infrastructure or remediate the space upon which the Company's communications infrastructure resides. Assetretirement obligations are included in "other long-term liabilities" on the Company's consolidated balance sheet. The liability accretes as a result of thepassage of time and the related accretion expense is included in "depreciation, amortization and accretion" on the Company's consolidated statement ofoperations and comprehensive income (loss). The associated asset retirement costs are capitalized as an additional carrying amount of the related long-livedasset and depreciated over the useful life of such asset.GoodwillGoodwill represents the excess of the purchase price for an acquired business over the allocated value of the related net assets. The Company testsgoodwill for impairment on an annual basis, regardless of whether adverse events or changes in circumstances have occurred. The annual test begins withgoodwill and all intangible assets being allocated to applicable reporting units. The Company's reporting units are the same as its operating segments(Towers and Fiber). The Company then performs a qualitative assessment to determine whether it is "more likely than not" that the fair value of the reportingunits is less than its carrying amount. If it is concluded that it is "more likely than not" that the fair value of a reporting unit is less than its carrying amount, itis necessary to perform the two-step goodwill impairment test. The two-step goodwill impairment test begins with a comparison of the estimated fair value ofthe reporting unit and the carrying value of the reporting unit. The first step, commonly referred to as a "step-one impairment test," is a screen for potentialimpairment while the second step measures the amount of impairment if there is an indication from the first step that one exists. The Company's measurementof the fair value for goodwill is based on an estimate of discounted expected future cash flows of the reporting unit. The Company performed its most recentannual goodwill impairment test as of October 1, 2017, which resulted in no impairments.Intangible AssetsIntangible assets are included in "site rental contracts and customer relationships, net" and "other intangible assets, net" on the Company's consolidatedbalance sheet and predominately consist of the estimated fair value of the following items recorded in conjunction with acquisitions: (1) site rental contractsand customer relationships, (2) below-market leases for land interest under the acquired communications infrastructure, or (3) other contractual rights such astrademarks. The site rental contracts and customer relationships intangible assets are comprised of (1) the current term of the existing leases, (2) the expectedexercise of the renewal provisions contained within the existing leases, which automatically occur under contractual provisions, or (3) any associatedrelationships that are expected to generate value following the expiration of all renewal periods under existing leases.The useful lives of intangible assets are estimated based on the period over which the intangible asset is expected to benefit the Company and givesconsideration to the expected useful life of other assets to which the useful life may relate. Amortization expense for intangible assets is computed using thestraight-line method over the estimated useful life of each of the intangible assets. The useful life of the site rental contracts and customer relationshipsintangible asset is limited by the maximum depreciable life of the communications infrastructure (20 years), as a result of the interdependency of thecommunications infrastructure and site rental leases. In contrast, the site rental contracts and customer relationships are estimated to provide economicbenefits for59NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)several decades because of the low rate of tenant cancellations and high rate of renewals experienced to date. Thus, while site rental contracts and customerrelationships are valued based upon the fair value, which includes assumptions regarding both (1) tenants' exercise of optional renewals contained in theacquired leases and (2) renewals of the acquired leases past the contractual term including exercisable options, the site rental contracts and customerrelationships are amortized over a period not to exceed 20 years as a result of the useful life being limited by the depreciable life of the communicationsinfrastructure.The carrying value of other intangible assets with finite useful lives will be reviewed for impairment whenever events or changes in circumstancesindicate that the carrying amount of the assets may not be recoverable. The Company has a dual grouping policy for purposes of determining the unit ofaccount for testing impairment of the site rental contracts and customer relationships intangible assets. First, the Company pools the site rental contracts andcustomer relationships with the related communications infrastructure assets into portfolio groups for purposes of determining the unit of account forimpairment testing. Second and separately, the Company evaluates the site rental contracts and customer relationships by significant tenant or by tenantgrouping for individually insignificant tenants, as appropriate. If the sum of the estimated future cash flows (undiscounted) expected to result from the use oreventual disposition of an asset is less than the carrying amount of the asset, an impairment loss is recognized. Measurement of an impairment loss is basedon the fair value of the asset.Deferred CreditsDeferred credits are included in "deferred revenues" and "other long-term liabilities" on the Company's consolidated balance sheet and consist of theestimated fair value of the following items recorded in conjunction with acquisitions: (1) below-market tenant leases for contractual interests with tenants onacquired communications infrastructure, which are amortized to site rental revenues and (2) above-market leases for land interests under the Company'scommunications infrastructure, which are amortized to site rental cost of operations.Fair value for these deferred credits represents the difference between (1) the stated contractual payments to be made pursuant to the in-place lease and(2) management's estimate of fair market lease rates for each corresponding lease. Deferred credits are measured over a period equal to the estimated remainingeconomic lease term considering renewal provisions or economics associated with those renewal provisions, to the extent applicable. Deferred credits areamortized over their respected estimated lease terms at the time of acquisition.Deferred Financing CostsThird-party costs incurred to obtain financing, with the exception of costs incurred related to revolving lines of credit, are deferred and are included as adirect deduction from the carrying amount of the related debt liability in "debt and other long-term obligations" on the Company's consolidated balancesheet. Third party costs incurred to obtain financing through a revolving line of credit are deferred and are included in "long-term prepaid rent and otherassets, net" on the Company's consolidated balance sheet.Revenue RecognitionSite rental revenues are recognized on a monthly basis over the fixed, non-cancelable term of the relevant contract (generally ranging from five to 15years for site rental revenues derived from wireless customers and three to 20 years for site rental revenues derived from the Company's fiber solutionsbusiness (including from organizations with high-bandwidth and multi-location demands)), regardless of whether the payments from the tenant are receivedin equal monthly amounts. Certain of the Company's contracts contain fixed escalation clauses (such as fixed dollar or fixed percentage increases) orinflation-based escalation clauses (such as those tied to the consumer price index ("CPI")). If the payment terms call for fixed escalations, upfront payments,or rent free periods, the revenue is recognized on a straight-line basis over the fixed, non-cancelable term of the agreement. When calculating straight-linerental revenues, the Company considers all fixed elements of tenant contractual escalation provisions, even if such escalation provisions contain a variableelement in addition to a minimum. The Company's assets related to straight-line site rental revenues include current amounts of $86.0 million and $67.2million included in "other current assets" and non-current amounts of $1.3 billion and $1.3 billion included in "deferred site rental receivables" for the yearsended December 31, 2017 and 2016, respectively. Amounts billed or received prior to being earned are deferred and reflected in "deferred revenues" and"other long-term liabilities."Network services revenues are recognized after completion of the applicable service. Nearly all of the installation services are billed on a cost-plusprofit basis and site development services are billed on a fixed fee basis.In jurisdictions where the Company determines that it is the principal taxpayer, taxes and surcharges are recorded on a gross basis. In jurisdictions wherethe Company determines that it is acting as a collection agent for the government authority (for example, in collecting sales taxes or value-added taxescollected from customers), such amounts are presented on a net basis.60NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)See also "Recent Accounting Pronouncements Not Yet Adopted" below for further discussion.Costs of OperationsApproximately 55% of the Company's site rental costs of operations expenses consist of Towers ground lease expenses, and the remainder includes fiberaccess expenses, property taxes, repairs and maintenance expenses, employee compensation or related benefit costs, or utilities. Generally, the ground leasesfor land are specific to each site and are for an initial term of five years and are renewable for pre-determined periods. The Company also enters into termeasements and ground leases in which it prepays the entire term in advance. Fiber access expenses primarily consist of leases of fiber assets and other accessagreements to facilitate the Company's communications infrastructure.Ground lease and fiber access expenses are recognized on a monthly basis, regardless of whether the payment terms require the Company to makepayments annually, quarterly, monthly, or for the entire term in advance. Certain of the Company's ground lease and fiber access agreements contain fixedescalation clauses (such as fixed dollar or fixed percentage increases) or inflation-based escalation clauses (such as those tied to the CPI). If the payment termsinclude fixed escalation provisions, the effect of such increases is recognized on a straight-line basis. The Company calculates the straight-line expense usinga time period that equals or exceeds the remaining depreciable life of the communications infrastructure asset. Further, when a tenant has exercisable renewaloptions that would compel the Company to exercise existing renewal options, the Company has straight-lined the expense over a sufficient portion of suchrenewals to coincide with the final termination of the tenant's renewal options. The Company's non-current liability related to straight-line expense isincluded in "other long-term liabilities" on the Company's consolidated balance sheet. The Company's assets related to prepaid agreements is included in"prepaid expenses" and "long-term prepaid rent and other assets, net" on the Company's consolidated balance sheet.Network services and other costs of operations predominately consist of third-party service providers such as contractors and professional services firmsand, to a lesser extent, internal labor costs.Acquisition and Integration CostsAll direct or incremental costs related to a business combination are expensed as incurred. Costs include severance, retention bonuses payable toemployees of an acquired enterprise, temporary employees to assist with the integration of the acquired operations, or fees paid for services such asconsulting, accounting, legal, or engineering reviews. These business combination costs are included in "acquisition and integration costs" on the Company'sconsolidated statement of operations and comprehensive income (loss). See note 4 for a discussion of the Company's recent acquisitions.Stock-Based CompensationRestricted Stock Units. The Company records stock-based compensation expense only for those unvested restricted stock units ("RSUs") for which therequisite service is expected to be rendered. The cumulative effect of a change in the estimated number of RSUs for which the requisite service is expected tobe or has been rendered is recognized in the period of the change in the estimate. To the extent that the requisite service is rendered, compensation cost foraccounting purposes is not reversed; rather, it is recognized regardless of whether or not the awards vest. A discussion of the Company's valuation techniquesand related assumptions and estimates used to measure the Company's stock-based compensation is as follows:Valuation. The fair value of RSUs without market conditions is determined based on the number of shares relating to such RSUs and the quoted price ofthe Company's common stock at the date of grant. The Company estimates the fair value of RSUs with market conditions granted using a Monte Carlosimulation. The Company's determination of the fair value of RSUs with market conditions on the date of grant is affected by its common stock price as wellas assumptions regarding a number of highly complex or subjective variables. The determination of fair value using a Monte Carlo simulation requires theinput of subjective assumptions, and other reasonable assumptions could provide differing results.Amortization Method. The Company amortizes the fair value of all RSUs on a straight-line basis for each separately vesting tranche of the award (gradedvesting schedule) over the requisite service periods.Expected Volatility. The Company estimates the volatility of its common stock at the date of grant based on the historical volatility of its commonstock.Expected Dividend Rate. The expected dividend rate at the date of grant is based on the then-current dividend yield.Risk-Free Rate. The Company bases the risk-free rate on the implied yield currently available on U.S. Treasury issues with an equivalent remaining termequal to the expected life of the award.61NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Forfeitures. The Company uses historical data and management's judgment about the future employee turnover rates to estimate the number of sharesfor which the requisite service period will not be rendered.Interest Expense and Amortization of Deferred Financing CostsThe components of interest expense and amortization of deferred financing costs are as follows: Years Ended December 31, 201720162015Interest expense on debt obligations$581,314 $500,699 $490,002Amortization of deferred financing costs and adjustments on long-term debt, net19,035 19,087 21,048Amortization of interest rate swaps— — 18,725Capitalized interest(11,545) (7,010) (4,805)Other1,878 2,256 2,158Total$590,682 $515,032 $527,128The Company amortizes deferred financing costs, discounts, premiums, and purchase price adjustments on long-term debt over the estimated term of therelated borrowing using the effective interest yield method. Discounts or purchase price adjustments are generally presented as a direct reduction to therelated debt obligation on the Company's consolidated balance sheet. Income TaxesThe Company operates as a REIT for U.S. federal income tax purposes. As a REIT, the Company is generally entitled to a deduction for dividends that itpays and therefore is not subject to U.S. federal corporate income tax on its taxable income that is currently distributed to its stockholders. The Company alsomay be subject to certain federal, state, local, and foreign taxes on its income and assets, including (1) alternative minimum taxes (repealed effective January1, 2018), (2) taxes on any undistributed income, (3) taxes related to the TRSs, (4) franchise taxes, (5) property taxes, and (6) transfer taxes. In addition, theCompany could in certain circumstances be required to pay an excise or penalty tax, which could be significant in amount, in order to utilize one or morerelief provisions under the Internal Revenue Code of 1986, as amended ("Code"), to maintain qualification for taxation as a REIT.During the fourth quarter of 2015, the Company completed the necessary steps to include small cells that were previously included in one or morewholly-owned TRSs in the REIT effective January 2016. As a result, during the fourth quarter of 2015, the Company de-recognized the related net deferredtax liabilities. Effective January 4, 2016, the Company's small cells that were previously included in one or more TRSs were included in the REIT. See note11.Additionally, the Company has included in TRSs certain other assets and operations. Those TRS assets and operations will continue to be subject, asapplicable, to federal and state corporate income taxes or to foreign taxes in the jurisdictions in which such assets and operations are located. The Company'sforeign assets and operations (including its tower operations in Puerto Rico) most likely will be subject to foreign income taxes in the jurisdictions in whichsuch assets and operations are located, regardless of whether they are included in a TRS or not. The Company will be subject to a federal corporate level taxrate (currently 21%) on the gain recognized from the sale of assets occurring within a specified period (generally 5 years) after the REIT conversion up to theamount of the built in gain that existed on January 1, 2014, which is based upon the fair market value of those assets in excess of the Company's tax basis onJanuary 1, 2014. This gain can be offset by any remaining federal net operating loss carryforwards ("NOLs").For the Company's TRSs, the Company accounts for income taxes using an asset and liability approach, which requires the recognition of deferredincome tax assets and liabilities for the expected future tax consequences of events that have been recognized in the Company's financial statements or taxreturns. Deferred income tax assets and liabilities are determined based on the temporary differences between the financial statement and tax bases of assetsand liabilities using enacted tax rates. A valuation allowance is provided on deferred tax assets if it is determined that it is "more likely than not" that theasset will not be realized. The Company records a valuation allowance against deferred tax assets when it is "more likely than not" that some portion or all ofthe deferred tax asset will not be realized. The Company reviews the recoverability of deferred tax assets each quarter and based upon projections of futuretaxable income, reversing deferred tax liabilities or other known events that are expected to affect future taxable income, records a valuation allowance forassets that do not meet the "more likely than not" realization threshold. Valuation allowances may be reversed if related deferred tax assets are deemedrealizable based upon changes in facts and circumstances that impact the recoverability of the asset.62NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)The Company recognizes a tax position if it is "more likely than not" that it will be sustained upon examination. The tax position is measured at thelargest amount that is greater than 50 percent likely of being realized upon ultimate settlement. The Company reports penalties and tax-related interestexpense as a component of the benefit (provision) for income taxes. As of December 31, 2017 and 2016, the Company has not recorded any penalties relatedto its income tax positions.See note 11.Per Share InformationBasic net income (loss) attributable to CCIC common stockholders, per common share excludes dilution and is computed by dividing net income (loss)attributable to CCIC common stockholders by the weighted-average number of common shares outstanding during the period. For the year ended December31, 2017, diluted net income (loss) attributable to CCIC common stockholders, per common share is computed by dividing net income (loss) attributable toCCIC common stockholders by the weighted-average number of common shares outstanding during the period plus any potential dilutive common shareequivalents, including shares issuable upon (1) the vesting of RSUs as determined under the treasury stock method and (2) conversion of the Company's6.875% Mandatory Convertible Preferred Stock, Series A, par value $0.01 per share ("6.875% Convertible Preferred Stock"), as determined under the if-converted method. For the years ended December 31, 2016 and December 31, 2015, diluted income (loss) attributable to CCIC common stockholders, percommon share is computed by dividing net income (loss) attributable to CCIC common stockholders by the weighted-average number of common sharesoutstanding during the period plus any potential dilutive common share equivalents, including shares issuable upon (1) the vesting of RSUs as determinedunder the treasury stock method and (2) conversion of the Company's then outstanding 4.50% Mandatory Convertible Preferred Stock, Series A, par value$0.01 per share ("4.50% Convertible Preferred Stock"), as determined under the if-converted method.A reconciliation of the numerators and denominators of the basic and diluted per share computations is as follows: Years Ended December 31, 201720162015Net income (loss) from continuing operations$444,550 $356,973 $525,286Dividends on preferred stock(58,294) (32,991) (43,988)Net income (loss) from continuing operations attributable to CCIC common stockholders for basicand diluted computations$386,256 $323,982 $481,298 Income (loss) from discontinued operations, net of tax— — 999,049Less: Net income (loss) attributable to the noncontrolling interest— — 3,343Net income (loss) from discontinued operations attributable to CCIC common stockholders forbasic and diluted computations— — 995,706 Weighted-average number of common shares outstanding (in thousands): Basic weighted-average number of common stock outstanding381,740 340,349 333,002Effect of assumed dilution from potential common shares relating to RSUs1,481 530 1,060Diluted weighted-average number of common shares outstanding383,221 340,879 334,062Net income (loss) attributable to CCIC common stockholders, per common share: Income (loss) from continuing operations, basic$1.01 $0.95 $1.45Income (loss) from discontinued operations, basic$— $— $2.99Net income (loss) attributable to CCIC common stockholders, basic$1.01 $0.95 $4.44Income (loss) from continuing operations, diluted$1.01 $0.95 $1.44Income (loss) from discontinued operations, diluted$— $— $2.98Net income (loss) attributable to CCIC common stockholders, diluted$1.01 $0.95 $4.42For the year ended December 31, 2017, 15.0 million common share equivalents related to the 6.875% Convertible Preferred Stock were excluded fromthe dilutive common shares because the impact of the conversion of such preferred stock would be anti-dilutive based on the Company's common stock priceas of December 31, 2017. For the year ended December 31, 2015, 11.4 million common share equivalents related to the then outstanding 4.50% ConvertiblePreferred Stock were excluded from the dilutive common shares because the impact of the conversion of such preferred stock would be anti-dilutive based onthe Company's common stock price at the end of such year. See notes 12 and 13.63NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Fair ValuesThe Company's assets and liabilities recorded at fair value are categorized based upon a fair value hierarchy that ranks the quality and reliability of theinformation used to determine fair value. The three levels of the fair value hierarchy are (1) Level 1 — quoted prices (unadjusted) in active and accessiblemarkets, (2) Level 2 — observable prices that are based on inputs not quoted in active markets but corroborated by market data, and (3) Level 3 —unobservable inputs and are not corroborated by market data. The Company evaluates fair value hierarchy level classifications quarterly, and transfersbetween levels are effective at the end of the quarterly period.The fair value of cash and cash equivalents and restricted cash approximate the carrying value. The Company determines the fair value of its debtsecurities based on indicative quotes (that is non-binding quotes) from brokers that require judgment to interpret market information including implied creditspreads for similar borrowings on recent trades or bid/ask prices or quotes from active markets if applicable. Foreign currency swaps are valued at settlementamounts using observable exchange rates and, if material, reflect an adjustment for the Company's and contract counterparty's credit risk. There were nochanges since December 31, 2016 in the Company's valuation techniques used to measure fair values. See note 10 for a further discussion of fair values. SwapsInterest Rate Swaps. The Company had previously entered into interest rate swaps to manage or reduce its interest rate risk, including the use of (1)forward-starting interest rate swaps to hedge its exposure to variability in future cash flows attributable to changes in LIBOR on anticipated financings,including refinancings and potential future borrowings or (2) interest rate swaps to hedge the interest rate variability on a portion of the Company's floatingrate debt. Derivative financial instruments were entered into for periods that matched the related underlying exposures. The Company can elect whether ornot to designate derivative financial instruments as accounting hedges. The Company can also enter into derivative financial instruments that are notdesignated as accounting hedges. As of December 31, 2017, the Company does not have any interest rate swaps.Derivatives were recognized on the consolidated balance sheet at fair value. If the derivative was designated as a cash flow hedge, the effective portionof the change in the fair value of the derivative was recorded as a separate component of stockholders' equity, captioned "accumulated other comprehensiveincome (loss)" on the Company's consolidated balance sheet, and recognized as increases or decreases to "interest expense and amortization of deferredfinancing costs" on the Company's consolidated statement of operations and comprehensive income (loss) when the hedged item affects earnings. If a hedgeceased to qualify for hedge accounting, any change in the fair value of the derivative since the date it ceased to qualify was recorded to "net gain (loss) oninterest rate swaps." However, any amounts previously recorded to "accumulated other comprehensive income (loss)" would remain there until the originalforecasted transaction affected earnings. In situations where it becomes probable that the hedged forecasted transaction will not occur, any gains or losses thathave been recorded to "accumulated other comprehensive income (loss)" are immediately reclassified to earnings.Foreign Currency Swaps. During 2015, the Company entered into foreign currency swaps to manage and reduce its foreign currency risk related to theMay 2015 sale of the Company's formerly 77.6% owned subsidiary that operated towers in Australia ("CCAL") (see note 3). The derivatives were recognizedon the consolidated balance sheet at fair value as of December 31, 2015. These swaps were not designated as accounting hedges and as such, thecorresponding gain (loss) on the fair value adjustment is included as a component of "other income (expense)" on the Company's consolidated statement ofoperations and comprehensive income (loss). See note 9. In January 2016, the then outstanding swap related to the installment payment received from theBuyer (as defined in note 3) was cash settled.Recently Adopted Accounting PronouncementsNo accounting pronouncements adopted during the year ended December 31, 2017 had a material impact on the Company's consolidated financialstatements.64NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Recent Accounting Pronouncements Not Yet AdoptedIn May 2014, the FASB released updated guidance regarding the recognition of revenue from contracts with customers, exclusive of those contractswithin lease accounting. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services tocustomers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that coreprinciple, an entity should apply the following steps: (1) identify the contracts with the customer; (2) identify the performance obligations in the contract; (3)determine the contract price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when (or as) theentity satisfies a performance obligation. This guidance is effective for the Company on January 1, 2018, following the FASB's July 2015 decision to deferthe effective date of the standard by one year. This guidance is required to be applied, at the Company's election, either (1) retrospectively to each priorreporting period presented, or (2) with the cumulative effect being recognized at the date of initial application. The Company will adopt the guidanceeffective January 1, 2018 with the cumulative effect being recognized at the date of initial application, and the adoption of this guidance will not have amaterial impact on its consolidated financial statements.In February 2016, the FASB issued new guidance on the recognition, measurement, presentation and disclosure of leases. The new guidance requireslessees to recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments for all leases with a term greaterthan 12 months. The accounting for lessors remains largely unchanged from existing guidance. This guidance is effective for the Company as of January 1,2019 and is required to be applied using a modified retrospective approach for all leases existing at, or entered into after, the beginning of the earliestcomparative period presented. Although early adoption is permitted, the Company does not expect to early adopt the new guidance prior to January 1, 2019.With regard to the application of this guidance to the Towers segment, the Company expects that (1) its Towers lessee arrangements will continue to beclassified as operating leases under the new guidance; (2) this guidance will have a material impact on its consolidated balance sheet due to the addition ofright-of-use assets and lease liabilities for all lessee arrangements with a term greater than 12 months; and (3) there will not be a material impact to itsconsolidated statement of operations and consolidated statement of cash flows. With regard to the application of this guidance to the Fiber segment, theCompany (1) has established and is progressing through the various steps of a cross-functional project plan to assess the impact of the standard; (2) expectsthis guidance to have a material impact on its consolidated balance sheet due to the addition of right-of-use assets and lease liabilities for all lesseearrangements with a term greater than 12 months; and (3) continues to assess additional impacts to its consolidated financial statements, including theconsolidated statement of operations and the consolidated statement of cash flows.In November 2016, the FASB issued new guidance which requires an entity's statement of cash flows to explain the change in restricted cash andrestricted cash equivalents in addition to cash and cash equivalents. This new guidance also requires an entity that includes cash, cash equivalents, restrictedcash and restricted cash equivalents on multiple lines on its balance sheet to present a reconciliation between its statement of cash flows and its balancesheet. The guidance is effective for the Company on January 1, 2018, and is required to be applied retrospectively to each prior reporting period presented.The Company will adopt this guidance effective January 1, 2018, and believes that the impact of the new guidance will be limited to certain changes inpresentation on the consolidated statement of cash flows.In January 2017, the FASB issued new guidance which clarifies the definition of a business in order to assist companies in evaluating whethertransactions should be accounted for as acquisitions or disposals of assets or businesses. The guidance is effective for the Company as of January 1, 2018, andis required to be applied prospectively. The Company will adopt this guidance effective January 1, 2018 and will apply the new guidance to prospectivetransactions. The adoption of this guidance will not have a material impact on the Company's consolidated financial statements.In January 2017, the FASB issued new guidance to simplify the accounting for goodwill impairment by removing the second step of the existinggoodwill impairment test. As a result of the guidance, goodwill impairment, if any, will be measured during the step-one impairment test as the amount bywhich a reporting unit's carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. Additionally, the guidance does not change theoption to complete a qualitative assessment prior to performing a step-one impairment test. The guidance is effective for the Company as of January 1, 2020.Early adoption is permitted. The Company is currently evaluating the impact of the guidance, including the impact on its consolidated financial statements.In February 2017, the FASB issued new guidance which clarifies the scope and application of accounting for the de-recognition of non-financial assetsand in substance non-financial assets, including sales and partial sales of real estate assets. The new guidance also eliminates the existing industry specificguidance for partial sales of real estate and requires full gain recognition upon partial sales of real estate. The guidance is effective for the Company as ofJanuary 1, 2018. The Company will adopt this guidance effective January 1, 2018, and the adoption of this guidance will not have a material impact on itsconsolidated financial statements.65NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)3.Discontinued OperationsOn May 14, 2015, the Company entered into a definitive agreement to sell CCAL to a consortium of investors led by Macquarie Infrastructure and RealAssets (collectively, "Buyer"). On May 28, 2015, the Company completed the sale. At closing, the Company received net proceeds of approximately $1.1billion after accounting for the Company's 77.6% ownership interest, repayment of intercompany debt owed to the Company by CCAL and estimatedtransaction fees and expenses, exclusive of the impact of foreign currency swaps related to the CCAL sale (see note 9).As part of the sale of CCAL, in January 2016, the Company received an installment payment from the Buyer totaling approximately $124 million,inclusive of the impact of the related foreign currency swap (see note 9).During the second quarter 2015, the Company used net proceeds from the sale of CCAL to repay portions of outstanding borrowings under theCompany's then outstanding senior secured credit facility ("2012 Credit Facility"). See note 8.The Company entered into foreign currency swaps to manage and reduce its foreign currency risk associated with the sale of CCAL. These swaps are notincluded in discontinued operations. See note 9.Prior to the sale of CCAL, it had historically been a separate operating segment of the Company. The sale of CCAL is treated as discontinued operationsfor all periods presented pursuant to ASU 2014-08, which the Company adopted on January 1, 2015. The sale of CCAL represented a strategic shift of theCompany to focus on its U.S. operations. The gain from disposal of CCAL is included in discontinued operations on the consolidated statement ofoperations. The tables below set forth the results of operations related to discontinued operations for the year ended December 31, 2015. Year Ended December 31, 2015(b)(c)Total revenues $65,293Total cost of operations (a) 17,498Depreciation, amortization and accretion 10,168Total other expenses 10,481Pre-tax income from discontinued operations 27,146Benefit (provision) from income taxes (7,456)Net income (loss) from discontinued operations(d) $19,690 (a)Exclusive of depreciation, amortization, and accretion shown separately.(b)No interest expense has been allocated to discontinued operations.(c)CCAL results are through May 28, 2015, which was the closing date of the Company's sale of CCAL.(d)Exclusive of the gain (loss) from disposal of discontinued operations, net of tax, as presented on the consolidated statement of operations.The Company recorded a gain on the sale of CCAL during the year ended December 31, 2015, which was comprised of the following items:Cash received from sale of CCAL(a)$1,139,369Installment payment receivable due January 2016(a)117,384Total proceeds from sale of CCAL$1,256,753Adjusted for: Net assets and liabilities related to discontinued operations(b)(c)258,575Transaction fees and expenses23,059Foreign currency translation reclassification adjustments(d)(25,678)Pre-tax gain (loss) from disposal of discontinued operations1,000,797Income taxes related to the sale of CCAL(21,438)Gain (loss) from disposal of discontinued operations$979,359 66NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)(a)Exclusive of foreign currency swaps and based on exchange rates as of May 28, 2015, which was the closing date of the Company's sale of CCAL. See note 9. The impact offluctuations in the exchange rate subsequent to the closing date are reflected as a component of "other income (expense)" on the Company's consolidated statement of operations.(b)Represents net assets attributable to CCIC, net of the disposition of noncontrolling interest of $23.5 million.(c)Inclusive of $11.1 million of cash.(d)Represents foreign currency translation adjustments previously included in "accumulated other comprehensive income (loss)" on the consolidated balance sheet and reclassified to"net gain (loss) from disposal of discontinued operations, net of tax" on the consolidated statement of operations and comprehensive income (loss).4.Acquisitions2015 Sunesys AcquisitionDuring April 2015, the Company entered into a definitive agreement to acquire Quanta Fiber Networks, Inc. ("Sunesys") for approximately $1.0 billionin cash, subject to certain limited adjustments ("Sunesys Acquisition"). On August 4, 2015, the Company closed the Sunesys Acquisition. The results ofoperations from Sunesys have been included in the Company's consolidated statement of operations since the date of acquisition.Prior to the closing, Sunesys was a wholly owned subsidiary of Quanta Services, Inc. and a fiber services provider that owned or had rights to nearly10,000 route miles of fiber in major metropolitan markets across the U.S., including Los Angeles, Philadelphia, Chicago, Atlanta, Silicon Valley, andnorthern New Jersey. Approximately 60% of Sunesys' fiber route miles were located in the top 10 basic trading areas.The Company utilized borrowings under the 2012 Credit Facility and cash on hand to fund the cash consideration of approximately $1.0 billion. Seenote 8.The final purchase price allocation for the Sunesys Acquisition is shown below.Final Purchase Price Allocation Current assets$15,306Property and equipment444,394Goodwill(a)331,775Other intangible assets, net254,079Current liabilities(20,233)Other non-current liabilities(37,356)Net assets acquired(b)$987,965 (a)The final purchase price allocation for the Sunesys Acquisition resulted in the recognition of goodwill based on the Company's expectation to leverage the Sunesys fiber footprintto support new small cells. The Sunesys fiber is complementary to the Company's existing fiber assets and is located where the Company expects to see wireless carrier networkinvestments.(b)Assets acquired in the Sunesys Acquisition are included in the Company's REIT and as such, no deferred taxes were recorded in connection with the Sunesys Acquisition.Net revenues and net income (loss) attributable to the Sunesys Acquisition are included in the Company's consolidated statements of operations andcomprehensive income (loss), since the date the acquisition was completed. For the years ended December 31, 2017, 2016 and 2015, the Sunesys Acquisitioncontributed consolidated net revenues of $121.7 million, $112.6 million and $41.4 million, respectively.2016 TDC AcquisitionIn April 2016, the Company acquired Tower Development Corporation ("TDC"), a portfolio of approximately 330 towers, for approximately $461.0million in cash ("TDC Acquisition"). The Company financed the acquisition with cash on hand, cash from borrowings under the Company's senior unsecuredrevolving credit facility ("2016 Revolver"), and cash from equity issuances under the ATM Program (see note 12). The final purchase price allocation wasprimarily comprised of customer relationships of approximately $140 million, property and equipment of approximately $107 million, and goodwill ofapproximately $211 million.2017 FiberNet AcquisitionOn November 1, 2016, the Company announced that it had entered into a definitive agreement to acquire FPL FiberNet Holdings, LLC and certainother subsidiaries of NextEra Energy, Inc. (collectively, "FiberNet") for approximately $1.5 billion in cash, subject to certain limited adjustments ("FiberNetAcquisition"). FiberNet is a fiber services provider in Florida and Texas that, as of the agreement date, owned or had rights to approximately 11,500 routemiles of fiber installed or under construction, inclusive of approximately 6,000 route miles in top metro markets. On January 17, 2017, the Company closedthe FiberNet67NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Acquisition, which was financed using proceeds from its November 2016 Common Stock Offering (as defined in note 12) and borrowings under the 2016Revolver (see note 8).The preliminary purchase price allocation for the FiberNet Acquisition is shown below and is based upon a preliminary valuation which is subject tochange as the Company obtains additional information with respect to fixed assets, intangible assets and certain liabilities.Preliminary Purchase Price Allocation Current assets$52,274Property and equipment438,478Goodwill(a)777,563Other intangible assets, net(b)327,338Other non-current assets2,449Current liabilities(41,120)Other non-current liabilities(36,152)Net assets acquired(c)$1,520,830 (a)The preliminary purchase price allocation for the FiberNet Acquisition resulted in the recognition of goodwill based on:•the Company's expectation to leverage the FiberNet fiber footprint to support new small cells and fiber solutions,•the complementary nature of the FiberNet fiber to the Company's existing fiber assets and its location in top metro markets where the Company expects to see wireless carriernetwork investments,•the Company's belief that the acquired fiber assets are well-positioned to benefit from the continued growth trends in the demand for data, and•other intangibles not qualified for separate recognition, including the assembled workforce.(b)Predominantly comprised of site rental contracts and customer relationships.(c)The vast majority of the assets will be included in the Company's REIT. As such, no deferred taxes were recorded in connection with the FiberNet Acquisition.2017 Wilcon AcquisitionOn April 17, 2017, the Company announced that it had entered into a definitive agreement to acquire Wilcon Holdings LLC ("Wilcon") from PamlicoHoldings and other unit holders of Wilcon for approximately $600 million in cash, subject to certain limited adjustments ("Wilcon Acquisition"). Wilcon is afiber services provider that owns approximately 1,900 route miles of fiber, primarily in Los Angeles and San Diego. On June 26, 2017, the Company closedthe Wilcon Acquisition, which was financed using proceeds from the May 2017 Common Stock Offering (as defined in note 12) and the 4.750% Senior Notes(as defined in note 8) offering.The preliminary purchase price of approximately $600 million was primarily comprised of other intangible assets (predominantly comprised of siterental contracts and customer relationships) of approximately $140 million, property and equipment of approximately $150 million, goodwill ofapproximately $360 million, offset by deferred revenues of approximately $40 million.The preliminary purchase price allocation for the Wilcon Acquisition resulted in the recognition of goodwill based on (1) the Company's expectation toleverage the Wilcon fiber footprint to support new small cells and fiber solutions, (2) the complementary nature of the Wilcon fiber to the Company's existingfiber assets and its location primarily in Los Angeles and San Diego, where the Company expects to see wireless carrier network investments, (3) theCompany's belief that the acquired fiber assets are well positioned to benefit from the continued growth trends in the demand for data, and (4) otherintangibles not qualified for separate recognition, including the assembled workforce. The preliminary purchase price allocation for the Wilcon Acquisitionis based upon a preliminary valuation which is subject to change as the Company obtains additional information with respect to fixed assets, intangibleassets and certain liabilities.68NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)2017 Lightower AcquisitionOn July 18, 2017, the Company announced that it had entered into a definitive agreement to acquire LTS Group Holdings LLC ("Lightower") fromBerkshire Partners, Pamlico Capital and other investors for approximately $7.1 billion in cash, subject to certain limited adjustments ("LightowerAcquisition"). Lightower owns or has rights to approximately 32,000 route miles of fiber located primarily in top metro markets in the Northeast, includingBoston, New York and Philadelphia. On November 1, 2017, the Company closed the Lightower Acquisition, which was financed using (1) cash on hand,including proceeds from the July 2017 Equity Offerings (as defined in note 12) and the August 2017 Senior Notes (as defined in note 8) offering, and (2)borrowings under the 2016 Revolver.The preliminary purchase price allocation for the Lightower Acquisition is shown below and is based upon a preliminary valuation which is subject tochange as the Company obtains additional information with respect to fixed assets, intangible assets and certain liabilities.Preliminary Purchase Price Allocation Current assets$104,643Property and equipment2,197,466Goodwill(a)3,116,010Other intangible assets, net(b)2,177,090Other non-current assets28,834Current liabilities(172,399)Other non-current liabilities(299,667)Net assets acquired(c)$7,151,977 (a)The preliminary purchase price allocation for the Lightower Acquisition resulted in the recognition of goodwill based on:•the Company's expectation to leverage the Lightower fiber footprint to support new small cells and fiber solutions,•the complementary nature of the Lightower fiber to the Company's existing fiber assets and its location where the Company expects to see wireless carrier networkinvestments,•the Company's belief that the acquired fiber assets are well-positioned to benefit from the continued growth trends in the demand for data, and•other intangibles not qualified for separate recognition, including the assembled workforce.(b)Predominantly comprised of site rental contracts and customer relationships.(c)The vast majority of the assets will be included in the Company's REIT. As such, no deferred taxes were recorded in connection with the Lightower Acquisition.Actual and Pro Forma Financial InformationNet revenues and net income (loss) attributable to acquisitions completed during the year ended December 31, 2017 are included in the Company'sconsolidated statements of operations and comprehensive income (loss), since the respective date each acquisition was completed. For the year endedDecember 31, 2017, the FiberNet Acquisition, Wilcon Acquisition and Lightower Acquisition (collectively, "2017 Acquisitions") resulted in an increase toconsolidated net revenues of $314.1 million.The unaudited pro forma financial results for the years ended December 31, 2017 and 2016 combine the historical results of the Company, along withthe historical results of the 2017 Acquisitions for the respective periods. The following table presents the unaudited pro forma consolidated results ofoperations of the Company as if each acquisition was completed as of January 1, 2016 for the periods presented below. The unaudited pro forma amounts arepresented for illustrative purposes only and are not necessarily indicative of future consolidated results of operations. Twelve Months EndedDecember 31, 2017 2016 Net revenues$5,050,166 $4,864,852 Income (loss) before income taxes541,389(b)(c) 367,326(b)(c)(d) Benefit (provision) for income taxes(28,960)(a) (20,968)(a) Net income (loss)$512,429(b)(c) $346,358(b)(c)(d) Basic net income (loss) attributable to CCIC common stockholders, per common share$0.89(c)(e) $0.51(c)(e) Diluted net income (loss) attributable to CCIC common stockholders, per common share$0.88(c)(e) $0.51(c)(e) (a)For the years ended December 31, 2017 and 2016, amounts are inclusive of pro forma adjustments to the benefit (provision) for income tax as a result of the Company's REITstatus. The vast majority of the assets and related income from the FiberNet Acquisition, the Wilcon Acquisition, and the Lightower69NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Acquisition are included in the Company's REIT. The remaining assets are included in the Company's TRS. For purposes of the unaudited pro forma financial results, anadjustment has been made to reflect the additional tax impact of the income related to the TRS assets.(b)For the years ended December 31, 2017 and 2016, amounts are inclusive of pro forma adjustments to depreciation and amortization of $247.1 million and $315.9 million,respectively, related to property and equipment and intangibles recorded as a result of the 2017 Acquisitions.(c)Pro forma amounts include the impact of the interest expense and common stock share issuances associated with the related debt and equity financings for the 2017 Acquisitions(see above and notes 8 and 12).(d)Amounts are inclusive of a total of $120 million of Lightower stock-based compensation expense and acquisition and integration costs.(e)Pro forma amounts include the impact of the preferred stock dividends related to the Mandatory Convertible Preferred Stock Offering (as defined in note 12) for the LightowerAcquisition (see above and note 12).5.Property and EquipmentThe major classes of property and equipment are as follows: Estimated Useful Lives As of December 31, 2017 2016Land(a)— $1,859,431 $1,747,335Buildings40 years 119,313 110,641Communications infrastructure assets1-20 years 17,183,482 13,825,394Information technology assets and other2-7 years 372,339 278,489Construction in process— 898,621 456,675Total gross property and equipment 20,433,186 16,418,534Less: accumulated depreciation (7,500,301) (6,613,219)Total property and equipment, net $12,932,885 $9,805,315 (a)Includes land owned in fee and perpetual easements.Depreciation expense for the years ended December 31, 2017, 2016 and 2015 was $914.9 million, $832.7 million and $774.9 million, respectively.Capital leases and associated leasehold improvements related to gross property and equipment, and accumulated depreciation was $4.3 billion and $1.7billion, respectively, as of December 31, 2017. See notes 1 and 2, including discussion of the Company's prepaid master lease agreements.6.Goodwill and Intangible AssetsGoodwillThe changes in the carrying value of goodwill for the years ended December 31, 2017 and December 31, 2016 were as follows:Balance as of December 31, 2015$5,513,551Additions due to TDC Acquisition(a)210,905Adjustments due to other acquisitions, purchase price allocations and other, net33,220Balance as of December 31, 2016$5,757,676Additions due to FiberNet Acquisition(b)777,563Additions due to Wilcon Acquisition(b)357,606Additions due to Lightower Acquisition(b)3,116,010Adjustments due to other acquisitions, purchase price allocations and other, net12,613Balance as of December 31, 2017$10,021,468 (a)The final purchase price allocation for the TDC Acquisition resulted in the recognition of goodwill in the Towers segment because of the anticipated growth opportunity in theacquired tower portfolio. See note 4.(b)The preliminary purchase price allocation for the FiberNet Acquisition, Wilcon Acquisition and Lightower Acquisition resulted in the recognition of goodwill in the Fiber segmentbased on:•the Company's expectation to leverage the FiberNet, Wilcon and Lightower fiber footprint to support new small cell and fiber solutions,•the complementary nature of the FiberNet, Wilcon and Lightower fiber to the Company's existing fiber assets and its location where the Company expects to see wirelesscarrier network investments,•the Company's belief that the acquired fiber assets are well-positioned to benefit from the continued growth trends in the demand for data, and70NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)•other intangibles not qualified for separate recognition, including the assembled workforce. See note 4.71NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)IntangiblesThe following is a summary of the Company's intangible assets. See note 4 for further discussion of the Company's acquisitions. As of December 31, 2017 As of December 31, 2016 Gross CarryingValue(a) AccumulatedAmortization Net Book Value Gross CarryingValue AccumulatedAmortization Net Book ValueSite rental contracts and customer relationships$7,782,934 $(2,156,499) $5,626,435 $5,146,301 $(1,847,523) $3,298,778Other intangible assets502,891 (167,567) 335,324 497,091 (145,797) 351,294Total$8,285,825 $(2,324,066) $5,961,759 $5,643,392 $(1,993,320) $3,650,072 (a)During the year ended December 31, 2017, intangible assets additions (primarily site rental contracts and customer relationships) from acquisitions had a weighted averageamortization period of approximately 17 years.Amortization expense related to intangible assets is classified as follows on the Company's consolidated statement of operations and comprehensiveincome (loss): For Years Ended December 31,Classification2017 2016 2015Depreciation, amortization and accretion$314,447 $264,656 $251,443Site rental costs of operations18,373 19,367 20,420Total amortization expense$332,820 $284,023 $271,863The estimated annual amortization expense related to intangible assets (inclusive of those recorded as an increase to "site rental costs of operations") forthe years ending December 31, 2018 to 2022 is as follows: Years Ending December 31, 20182019202020212022Estimated annual amortization$445,849 $444,889 $444,589 $444,155 $443,6887.Other LiabilitiesOther long-term liabilitiesThe following is a summary of the components of "other long-term liabilities" as presented on the Company's consolidated balance sheet. See also note2. December 31, 2017 2016Deferred rental revenues $1,076,845 $983,263Deferred ground lease payable 559,556 517,281Above market leases for land interests, net 201,542 224,126Deferred credits, net 531,856 207,992Asset retirement obligation 173,733 146,100Deferred income tax liabilities 5,192 8,075Other long-term liabilities 5,313 392Total $2,554,037 $2,087,22972NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Pursuant to its ground lease, easement and leased facility agreements, the Company has the obligation to perform certain asset retirement activities,including requirements upon contract termination to remove communications infrastructure or remediate the space upon which its communicationsinfrastructure resides. Accretion expense related to liabilities for retirement obligations amounted to $13.1 million, $11.3 million and $9.9 million for theyears ended December 31, 2017, 2016, and 2015, respectively. As of December 31, 2017 and 2016, liabilities for retirement obligations were $173.7 millionand $146.1 million, respectively, representing the net present value of the estimated expected future cash outlay. As of December 31, 2017, the estimatedundiscounted future cash outlay for asset retirement obligations was approximately $1.2 billion. See note 2.For the years ended December 31, 2017, 2016 and 2015, the Company recorded $19.3 million, $21.0 million and $22.5 million, respectively, as adecrease to "site rental costs of operations" for the amortization of above-market leases for land interests under the Company's towers. The estimatedamortization expense related to above-market leases for land interests under the Company's towers recorded to site rental costs of operations for the yearsending December 31, 2018 to 2022 is as follows: Years Ending December 31, 2018 2019 2020 2021 2022Above-market leases for land interests$18,277 $17,674 $16,769 $15,667 $14,580For the years ended December 31, 2017, 2016 and 2015, the Company recognized $37.3 million, $33.6 million and $32.8 million, respectively, in "siterental revenues" related to the amortization of below market tenant leases. The following table summarizes the estimated annual amounts related to below-market tenant leases expected to be amortized into site rental revenues for the years ending December 31, 2018 to 2022 are as follows: Years Ending December 31, 20182019202020212022Below-market tenant leases$65,104 $59,145 $53,050 $49,745 $44,910Other accrued liabilitiesOther accrued liabilities included accrued payroll and other accrued compensation of $141.0 million and $100.9 million, respectively, as of December31, 2017 and 2016.73NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)8.Debt and Other ObligationsSee note 19 for a discussion of the Company's issuance of the January 2018 Senior Notes (as defined in note 19) and the application of the net proceedstherefrom.The table below sets forth the Company's debt and other obligations as of December 31, 2017. OriginalIssue Date ContractualMaturityDate Outstanding Balance as ofDecember 31, StatedInterest Rateas ofDecember 31, 2017 2016 2017(a) Bank debt – variable rate: 2016 RevolverJan. 2016 Aug. 2022 $980,000(b) $— 2.6%(c) 2016 Term Loan AJan. 2016 Aug. 2022 2,396,588 1,954,173 2.6%(c) Total bank debt 3,376,588 1,954,173 Securitized debt – fixed rate: Secured Notes, Series 2009-1, Class A-1Jul. 2009 Aug. 2019(d) 31,813 51,416 6.3% Secured Notes, Series 2009-1, Class A-2Jul. 2009 Aug. 2029(d) 69,500 68,737 9.0% Tower Revenue Notes, Series 2010-3Jan. 2010 Jan. 2040(e)(f) 1,246,106 1,244,237 6.1% Tower Revenue Notes, Series 2010-6Aug. 2010 Aug. 2040(e)(f) 995,354 993,557 4.9% Tower Revenue Notes, Series 2015-1May 2015 May 2042(e)(f) 297,211 296,573 3.2% Tower Revenue Notes, Series 2015-2May 2015 May 2045(e)(f) 692,325 691,285 3.7% Total securitized debt 3,332,309 3,345,805 Bonds – fixed rate: 5.250% Senior NotesOct. 2012 Jan. 2023 1,639,207 1,637,099 5.3% 3.849% Secured NotesDec. 2012 Apr. 2023 992,663 991,279 3.8% 4.875% Senior NotesApr. 2014 Apr. 2022 842,090 840,322 4.9% 3.400% Senior NotesFeb./May 2016 Feb. 2021 849,859 849,698 3.4% 4.450% Senior NotesFeb. 2016 Feb. 2026 891,145 890,118 4.5% 3.700% Senior NotesMay 2016 June 2026 742,727 741,908 3.7% 2.250% Senior NotesSept. 2016 Sept. 2021 695,383 693,893 2.3% 4.000% Senior NotesFeb. 2017 Mar. 2027 493,833 — 4.0% 4.750% Senior NotesMay 2017 May 2047 343,209 — 4.8% 3.200% Senior NotesAug. 2017 Sept. 2024 741,859 — 3.2% 3.650% Senior NotesAug. 2017 Sept. 2027 990,965 — 3.7% Total bonds 9,222,940 6,644,317 Other: Capital leases and other obligationsVarious Various(g) 227,783 226,847 Various Total debt and other obligations 16,159,620 12,171,142 Less: current maturities and short-term debt and other currentobligations 115,251 101,749 Non-current portion of long-term debt and other long-termobligations $16,044,369 $12,069,393 (a)Represents the weighted-average stated interest rate.(b)As of December 31, 2017, the undrawn availability under the 2016 Revolver was $2.5 billion. See note 19.(c)The 2016 Revolver and senior unsecured term loan A facility ("2016 Term Loan A") bear interest at a rate per annum equal to LIBOR plus a credit spread ranging from 1.125%to 2.000%, based on the Company's senior unsecured debt rating. The Company pays a commitment fee of approximately 0.200% per annum on the undrawn available amountunder the 2016 Revolver.(d)The Secured Notes, Series 2009-1, Class A-1 and Secured Notes, Series 2009-1, Class A-2 are collectively referred to herein as "2009 Securitized Notes."(e)The Tower Revenue Notes, Series 2010-3 ("January 2010 Tower Revenue Notes"), Tower Revenue Notes, Series 2010-6 ("August 2010 Tower Revenue Notes") and TowerRevenue Notes, Series 2015-1 and 2015-2 ("May 2015 Tower Revenue Notes") are collectively referred to herein as "Tower Revenue Notes."(f)If the respective series of Tower Revenue Notes are not paid in full on or prior to an applicable anticipated repayment date, then Excess Cash Flow (as defined in the indenture) ofthe issuers of such notes will be used to repay principal of the applicable series and class of the Tower Revenue Notes, and additional interest (of an additional approximately5% per annum) will accrue on the respective Tower Revenue Notes. As of December 31, 2017, the Tower Revenue Notes have principal amounts of $2.3 billion, $300.0 millionand $700.0 million, with anticipated repayment dates in 2020, 2022 and 2025, respectively. See note 19.74NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)(g)The Company's capital leases and other obligations relate to land, fiber, vehicles, and other assets and bear interest rates ranging up to 10% and mature in periods ranging fromless than one year to approximately 30 years.The credit agreement governing the Company's 2016 Credit Facility contains financial maintenance covenants. The Company is currently incompliance with these financial maintenance covenants, and based upon current expectations, the Company believes it will continue to comply with itsfinancial maintenance covenants. In addition, certain of the Company's debt agreements also contain restrictive covenants that place restrictions on CCIC orits subsidiaries and may limit the Company's ability to, among other things, incur additional debt and liens, purchase the Company's securities, make capitalexpenditures, dispose of assets, undertake transactions with affiliates, make other investments, pay dividends or distribute excess cash flow.Bank DebtIn January 2016, the Company completed the 2016 Credit Facility, which was originally comprised of (1) a $2.5 billion 2016 Revolver maturing inJanuary 2021, (2) a $2.0 billion 2016 Term Loan A maturing in January 2021 and (3) a $1.0 billion senior unsecured 364-day revolving credit facility ("364-Day Facility") maturing in January 2017. The Company used the net proceeds from the 2016 Credit Facility (1) to repay the then outstanding 2012 CreditFacility and (2) for general corporate purposes. In February 2016, the Company used a portion of the net proceeds from the February 2016 Senior Notes (asdefined below) offering to repay in full all outstanding borrowings under the then outstanding 364-Day Facility.In February 2017, the Company entered into an amendment to the 2016 Credit Facility to (1) incur additional term loans in an aggregate principalamount of $500.0 million and (2) extend the maturity of both the 2016 Term Loan A and the 2016 Revolver to January 2022.In August 2017, the Company entered into an amendment to the 2016 Credit Facility to (1) increase the commitments under the 2016 Revolver by $1.0billion, for total commitments of $3.5 billion, and (2) extend the maturity of both the 2016 Term Loan A and the 2016 Revolver to August 2022.Securitized DebtThe Tower Revenue Notes and the 2009 Securitized Notes (collectively, "Securitized Debt") are obligations of special purpose entities and their directand indirect subsidiaries (each an "issuer"), all of which are wholly-owned, indirect subsidiaries of CCIC. The Tower Revenue Notes and 2009 SecuritizedNotes are governed by separate indentures. The January 2010 Tower Revenue Notes, August 2010 Tower Revenue Notes and May 2015 Tower RevenueNotes are governed by one indenture and consist of multiple series of notes, each with its own anticipated repayment date.The net proceeds of the January 2010 Tower Revenue Notes and August 2010 Tower Revenue Notes were primarily used to repay the portion of the2005 Tower Revenue Notes and 2006 Tower Revenue Notes not previously purchased. In April 2014, the Company utilized a portion of the net proceedsfrom the 4.875% Senior Notes (as defined below) offering to repay $300.0 million of the January 2010 Tower Revenue Notes which had an anticipatedrepayment date of January 2015.The net proceeds of the May 2015 Tower Revenue Notes, together with proceeds received from the Company's sale of CCAL, were primarily used to (1)repay $250.0 million aggregate principal amount of August 2010 Tower Revenue Notes which had an anticipated repayment date of August 2015, (2) repayall of the then outstanding WCP Secured Wireless Site Contracts Revenue Notes, Series 2010-1 ("WCP Securitized Notes"), (3) repay portions of outstandingborrowings under the 2012 Credit Facility and (4) pay related fees and expenses.The Securitized Debt is paid solely from the cash flows generated by the operation of the towers held directly and indirectly by the issuers of therespective Securitized Debt. The Securitized Debt is secured by, among other things, (1) a security interest in substantially all of the applicable issuers'assignable personal property, (2) a pledge of the equity interests in each applicable issuer and (3) a security interest in the applicable issuers' leases withtenants to lease tower space (space licenses). The governing instruments of two indirect subsidiaries ("Crown Atlantic" and "Crown GT") of the issuers of theTower Revenue Notes generally prevent them from issuing debt and granting liens on their assets without the approval of a subsidiary of VerizonCommunications. Consequently, while distributions paid by Crown Atlantic and Crown GT will service the Tower Revenue Notes, the Tower Revenue Notesare not obligations of, nor are the Tower Revenue Notes secured by the cash flows or any other assets of, Crown Atlantic and Crown GT. As of December 31,2017, the Securitized Debt was collateralized with personal property and equipment with an aggregate net book value of approximately $1.1 billion,exclusive of Crown Atlantic and Crown GT personal property and equipment.The excess cash flows from the issuers of the Securitized Debt, after the payment of principal, interest, reserves, expenses and management fees, aredistributed to the Company in accordance with the terms of the indentures. If the Debt Service Coverage75NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Ratio ("DSCR") (as defined in the applicable governing loan agreement) as of the end of any calendar quarter falls to a certain level, then all excess cash flowof the issuers of the applicable debt instrument will be deposited into a reserve account instead of being released to the Company. The funds in the reserveaccount will not be released to the Company until the DSCR exceeds a certain level for two consecutive calendar quarters. If the DSCR falls below a certainlevel as of the end of any calendar quarter, then all cash on deposit in the reserve account along with future excess cash flows of the issuers will be applied toprepay the debt with applicable prepayment consideration.The Company may repay the Tower Revenue Notes or the 2009 Securitized Notes in whole or in part at any time after the second anniversary of theapplicable issuance date, provided such prepayment is accompanied by any applicable prepayment consideration. The Securitized Debt has covenants andrestrictions customary for rated securitizations, including provisions prohibiting the issuers from incurring additional indebtedness or further encumberingtheir assets.See note 19 for a discussion of the redemption of the January 2010 Tower Revenue Notes.Bonds—Senior NotesIn February 2017, the Company issued $500.0 million aggregate principal amount of 4.000% senior unsecured notes due March 2027 ("4.000% SeniorNotes"). The Company used the net proceeds from the 4.000% Senior Notes offering to repay a portion of the outstanding borrowings under the 2016Revolver.In May 2017, the Company issued $350.0 million aggregate principal amount of 4.750% senior unsecured notes due May 2047 ("4.750% SeniorNotes"). The Company used the net proceeds from the 4.750% Senior Notes offering to partially fund the Wilcon Acquisition and to repay a portion of theoutstanding borrowings under the 2016 Revolver.In August 2017, the Company issued $1.75 billion aggregate principal amount of senior unsecured notes ("August 2017 Senior Notes"), whichconsisted of (1) $750.0 million aggregate principal amount of 3.200% senior unsecured notes due September 2024 ("3.200% Senior Notes") and (2) $1.0billion aggregate principal amount of 3.650% senior unsecured notes due September 2027 ("3.650% Senior Notes"). The Company used the net proceedsfrom the August 2017 Senior Notes offering to partially fund the Lightower Acquisition and pay related fees and expenses.In February 2016, the Company issued $1.5 billion aggregate principal amount of senior unsecured notes ("February 2016 Senior Notes"), whichconsisted of (1) $600.0 million aggregate principal amount of 3.400% senior notes due February 2021 ("3.400% Senior Notes") and (2) $900.0 millionaggregate principal amount of 4.450% senior unsecured notes due February 2026 ("4.450% Senior Notes"). The Company used the net proceeds from theFebruary 2016 Senior Notes offering, together with cash on hand, to (1) repay in full all outstanding borrowings under the then outstanding 364-Day Facilityand (2) repay $500.0 million of outstanding borrowings under the 2016 Revolver.In May 2016, the Company issued $1.0 billion aggregate principal amount of senior unsecured notes ("May 2016 Senior Notes"), which consisted of (1)$250.0 million aggregate principal amount of additional 3.400% Senior Notes pursuant to the same indenture as the 3.400% Senior Notes issued in theFebruary 2016 Senior Notes offering and (2) $750.0 million aggregate principal amount of 3.700% senior unsecured notes due June 2026 ("3.700% SeniorNotes"). The Company used the net proceeds from the May 2016 Senior Notes offering to repay in full the Tower Revenue Notes, Series 2010-2 and Series2010-5, each issued by certain of its subsidiaries, and to repay a portion of the outstanding borrowings under the 2016 Revolver.In September 2016, the Company issued $700.0 million aggregate principal amount of 2.250% senior unsecured notes ("2.250% Senior Notes") dueSeptember 2021. The Company used the net proceeds from the 2.250% Senior Notes offering to (1) repay $500.0 million aggregate principal amount of2.381% secured notes due 2017 ("2.381% Secured Notes") issued by certain of its subsidiaries and (2) repay a portion of the outstanding borrowings underthe 2016 Revolver.In April 2014, the Company issued $850.0 million aggregate principal amount of 4.875% senior unsecured notes due April 2022 ("4.875% SeniorNotes"). The net proceeds from the offering were approximately $839.0 million, after the deduction of associated fees. The Company utilized the net proceedsfrom the 4.875% Senior Notes offering (1) to repay $300.0 million of the January 2010 Tower Revenue Notes with an anticipated repayment date of January2015 and (2) to redeem all of the then outstanding 7.125% senior unsecured notes due 2019.In October 2012, the Company issued $1.65 billion aggregate principal amount of 5.250% senior unsecured notes due 2023 ("5.250% Senior Notes").The Company used the net proceeds from the 5.250% Senior Notes offering to partially fund the T-Mobile Acquisition.76NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Each of the February 2016 Senior Notes, May 2016 Senior Notes, 2.250% Senior Notes, 4.875% Senior Notes, 5.250% Senior Notes, 4.000% SeniorNotes, 4.750% Senior Notes, August 2017 Senior Notes (collectively, "Senior Notes") are senior unsecured obligations of the Company and rank equally withall of the Company's existing and future senior unsecured indebtedness, including obligations under the 2016 Credit Facility, and senior to all of theCompany's future subordinated indebtedness. The Senior Notes are structurally subordinated to all existing and future liabilities and obligations of theCompany's subsidiaries. The Company's subsidiaries are not guarantors of the Senior Notes.CCIC may redeem any of the Senior Notes in whole or in part at any time at a price equal to 100% of the principal amount to be redeemed, plus a makewhole premium, if applicable, and accrued and unpaid interest, if any to the date of redemption.Bonds—Secured NotesIn December 2012, the Company issued $1.0 billion aggregate principal amount of 3.849% secured notes due 2023 ("3.849% Secured Notes"). The2012 Secured Notes were issued and are guaranteed by the same subsidiaries of CCIC that had previously issued and guaranteed the 7.750% senior unsecurednotes due 2017 ("7.750% Secured Notes"). The 3.849% Secured Notes are secured by a pledge of the equity interests of such subsidiaries. The 3.849%Secured Notes are not guaranteed by and are not obligations of CCIC or any of its subsidiaries other than the issuers and guarantors of the 3.849% SecuredNotes. The 3.849% Secured Notes will be paid solely from the cash flows generated from operations of the towers held directly and indirectly by the issuersand the guarantors of such notes. The Company used the net proceeds from the issuance of the 3.849% Secured Notes to repurchase and redeem the thenoutstanding 7.750% Secured Notes and a portion of the then outstanding 9.000% senior notes due 2011. The 3.849% Secured Notes may be redeemed at anytime at a price equal to 100% of the principal amount, plus a make whole premium, and accrued and unpaid interest, if any to the redemption date.Previously Outstanding IndebtednessSee above for a discussion of the Company's recent redemptions and repayments of debt.Contractual MaturitiesThe following are the scheduled contractual maturities of the total debt or other long-term obligations outstanding at December 31, 2017. Thesematurities reflect contractual maturity dates and do not consider the principal payments that will commence following the anticipated repayment dates on theTower Revenue Notes. If the Tower Revenue Notes are not paid in full on or prior to their respective anticipated repayment dates, as applicable, then theExcess Cash Flow (as defined in the indenture) of the issuers of such notes will be used to repay principal of the applicable series and class of the TowerRevenue Notes and additional interest (of an additional approximately 5% per annum) will accrue on the Tower Revenue Notes. Years Ending December 31, 2018 2019 2020 2021 2022 Thereafter Total CashObligations UnamortizedAdjustments, Net Total Debt andOther ObligationsOutstandingScheduledcontractualmaturities$116,045 $167,458 $155,051 $1,824,568 $3,701,737 $10,296,901 $16,261,760 $(102,140) $16,159,620Debt Purchases and RedemptionsThe following is a summary of the purchases and redemptions of debt during the years ended December 31, 2017, 2016 and 2015. Year Ending December 31, 2017 Principal Amount Cash Paid Gains (losses)(a)2016 Term Loan A$— $— $(3,525) (a)The losses related to write off of deferred financing costs.77NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts) Year Ending December 31, 2016 Principal Amount Cash Paid(a) Gains (losses)(b)Revolving Credit Facility under 2012 Credit Facility$— $— $(1,930)Tranche A Term Loans under 2012 Credit Facility629,375 629,375 (1,498)Tranche B Term Loans under 2012 Credit Facility2,247,015 2,247,015 (27,122)Tower Revenue Notes, Series 2010-2350,000 352,796 (3,338)Tower Revenue Notes, Series 2010-5300,000 307,176 (8,129)2.381% Secured Notes500,000 508,472 (10,274)Total$4,026,390 $4,044,834 $(52,291) (a)Exclusive of accrued interest.(b)Inclusive of $33.8 million related to the write off of deferred financing costs. Year Ending December 31, 2015 Principal Amount Cash Paid(a) Gains (losses)(b)Tower Revenue Notes, Series 2010-4$250,000 $250,000 $(159)WCP Securitized Notes252,830 252,830 2,105Tranche B Term Loans under 2012 Credit Facility564,137 564,137 (6,127)Other2,394 2,370 24Total$1,069,361 $1,069,337 $(4,157) (a)Exclusive of accrued interest.(b)Inclusive of $4.2 million related to the write off of deferred financing costs, premiums and discounts.9.SwapsForeign Currency SwapsDuring May 2015, the Company entered into two previously outstanding foreign currency swaps to manage and reduce its foreign currency risk relatedto its sale of CCAL (see note 3). The Company does not enter into foreign currency swaps for speculative or trading purposes. The foreign currency swapswere originally comprised of the following:Item Swapped NotionalAmount Forward Rate Start Date End Date Pay Amount ReceiveAmount Fair Value atDecember 31, 2017 May 2015 cash receipt fromsale of CCAL A$1,400,000 0.8072 May 2015 June 2015 AustralianDollar US Dollar N/A(a) Installment payment fromBuyer A$155,000 0.79835 May 2015 January 2016 AustralianDollar US Dollar N/A(b) (a)In conjunction with closing the CCAL sale on May 28, 2015, the Company cash settled the swap with a notional value of Australian dollar $1.4 billion and recorded a gain onforeign currency swaps of $54.5 million, which is included as a component of "other income (expense)" on the Company's consolidated statement of operations.(b)As of December 31, 2015, the Company marked-to-market the swap with a notional value of Australian dollar $155.0 million and recorded (1) an asset within "other currentassets" on the Company's consolidated balance sheet and (2) a corresponding gain on foreign currency swaps, which is included as a component of "other income (expense)" onthe Company's consolidated statement of operations. In January 2016, the then outstanding swap related to the installment payment received from the Buyer was settled.In total, the Company recorded a gain on foreign currency swaps of $65.2 million for the year ended December 31, 2015, respectively. This gain isincluded as a component of "other income (expense)" on the Company's consolidated statement of operations.78NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)10.Fair Value DisclosuresThe following table shows the estimated fair values of the Company's financial instruments, along with the carrying amounts of the related assets(liabilities). See also note 2. Level in FairValue Hierarchy December 31, 2017 December 31, 2016 CarryingAmount FairValue CarryingAmount FairValueAssets: Cash and cash equivalents1 $314,094 $314,094 $567,599 $567,599Restricted cash1 126,065 126,065 129,547 129,547Liabilities: Debt and other obligations2 $16,159,620 $16,643,725 $12,171,142 $12,660,01311.Income TaxesIncome (loss) from continuing operations before income taxes by geographic area is as follows: Years Ended December 31, 2017 2016 2015Domestic$450,771 $349,041 $461,293Foreign(a)19,822 24,813 12,536Total$470,593 $373,854 $473,829 (a)Inclusive of income (loss) before income taxes from Puerto Rico.The benefit (provision) for income taxes consists of the following: Years Ended December 31, 201720162015Current: Federal$(2,816) $(227) $495Foreign(6,050) (6,820) (5,675)State(2,289) (1,231) (3,981)Total current(11,155) (8,278) (9,161)Deferred: Federal(17,743) (7,968) 44,716Foreign2,883 (601) (1,048)State(28) (34) 16,950Total deferred(14,888) (8,603) 60,618Total tax benefit (provision)$(26,043) $(16,881) $51,45779NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)A reconciliation between the benefit (provision) for income taxes and the amount computed by applying the federal statutory income tax rate to theincome (loss) before income taxes is as follows: Years Ended December 31, 20172016 2015Benefit (provision) for income taxes at statutory rate$(164,707) $(130,849) $(165,840)Tax effect of foreign income (losses)(430) 1,215 (527)Tax adjustment related to REIT operations158,812 121,092 186,649Tax adjustment related to the inclusion of small cells in the REIT(a)— — 33,759Expenses for which no federal tax benefit was recognized(42) (43) (414)Valuation allowances21 (21) 3,000State tax (provision) benefit, net of federal(2,115) (1,085) 1,210Foreign tax(3,168) (7,421) (6,723)Effects of tax law change(b)(14,628) — —Other214 231 343Total$(26,043) $(16,881) $51,457 (a)During the fourth quarter of 2015, the Company de-recognized the net deferred tax liabilities related to the Company's small cells previously included in one or more TRSs inconjunction with the inclusion of small cells in the REIT in January 2016.(b)Pursuant to the Tax Cuts and Jobs Act, which was signed into law in December 2017, the Company was required to write down its net federal deferred tax asset in the amount of$16.8 million as a result of the reduction in the federal corporate tax rate offset by a benefit of $2.2 million related to the refund of the Company's alternative minimum tax creditcarryforward.The components of the net deferred income tax assets and liabilities are as follows: December 31, 2017 2016Deferred income tax liabilities: Property and equipment$4,940 $3,945Deferred site rental receivable6,907 6,192Total deferred income tax liabilities11,84710,137Deferred income tax assets: Intangible assets4,460 22,377Net operating loss carryforwards20,800 21,143Deferred ground lease payable2,060 1,646Accrued liabilities5,161 5,511Receivables allowance317 383Other1,431 1,726Valuation allowances(1,172) (6,627)Total deferred income tax assets, net33,057 46,159Net deferred income tax asset (liabilities)$21,210 $36,022The Company operates as a REIT for U.S. federal income tax purposes.The components of the net deferred income tax assets (liabilities) are as follows: December 31, 2017 December 31, 2016ClassificationGross ValuationAllowance Net Gross ValuationAllowance NetFederal$25,260 $— $25,260 $42,948 $(21) $42,927State1,142 — 1,142 1,170 — 1,170Foreign(4,020) (1,172) (5,192) (1,469) (6,606) (8,075)Total$22,382 $(1,172) $21,210 $42,649 $(6,627) $36,02280NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)At December 31, 2017, the Company had U.S. federal and state NOLs of approximately $1.5 billion and $0.6 billion, respectively, which are availableto offset future taxable income. These amounts include approximately $237.0 million of losses related to stock-based compensation. The Company also hasforeign NOLs of $53.2 million. If not utilized, the Company's U.S. federal NOLs expire starting in 2024 and ending in 2036, the state NOLs expire starting in2018 and ending in 2036, and the foreign NOLs expire starting in 2022 and ending in 2037. The utilization of the NOLs is subject to certain limitations. TheCompany's U.S. federal and state income tax returns generally remain open to examination by taxing authorities until three years after the applicable NOLshave been used or expired. The remaining valuation allowance relates to certain foreign net deferred tax assets (primarily NOLs).As of December 31, 2017, there were no unrecognized tax benefits that would impact the effective tax rate, if recognized. The aggregate changes in thebalance of unrecognized tax benefits are as follows: Years Ended December 31, 2017 2016Balance at beginning of year$3,080 $6,770Additions based on prior year tax positions— 116Reductions as a result of the lapse of statute limitations(3,080) (3,806)Balance at end of year$— $3,080From time to time, the Company is subject to examinations by various tax authorities in jurisdictions in which the Company has business operations.At this time, the Company is not subject to an Internal Revenue Service examination. The Australian Taxation Office is conducting an audit of the taxconsequences for Australian tax purposes of the Company's sale of CCAL. The Company regularly assesses the likelihood of additional assessments in eachof the tax jurisdictions. The Company believes it has adequately provided for uncertain tax positions and does not believe assessments, if any, arising fromcurrent or future examination or audits will have a material effect on the Company's financial statements.As of December 31, 2017, the Company's deferred tax assets are included in "long-term prepaid rent and other assets, net" and the Company's deferredtax liabilities are included in "other long-term liabilities" on the Company's consolidated balance sheet.12.Equity"At-The-Market" Stock Offering ProgramThe Company maintains an "at-the-market" stock offering program ("ATM Program") through which it may, from time to time, issue and sell shares of itscommon stock having an aggregate cumulative gross sales price of up to $500.0 million to or through sales agents. Sales, if any, under the ATM Program maybe made by means of ordinary brokers' transactions on the New York Stock Exchange or otherwise at market prices prevailing at the time of sale, at pricesrelated to prevailing market prices or, subject to specific instructions of the Company, at negotiated prices. The Company intends to use the net proceedsfrom any sales under the ATM Program for general corporate purposes, which may include the funding of future acquisitions or investments and therepayment or repurchase of any outstanding indebtedness. During the year ended December 31, 2017, 0.2 million shares of common stock were sold underthe ATM Program, generating net proceeds of $22.0 million after giving effect to sales commissions of $0.2 million. During the year ended December 31,2016, 3.8 million shares of common stock were sold under the ATM Program, generating net proceeds of $323.8 million after giving effect to sales agentcommissions of $3.3 million. The net proceeds from the sales under the ATM Program were used, in part, to fund the TDC Acquisition. As of December 31,2017, the Company had approximately $150 million of gross sales of common stock availability remaining under the ATM Program.May 2017 Common Stock OfferingOn May 1, 2017, the Company completed an offering of 4.75 million shares of its common stock, which generated net proceeds ofapproximately $442.0 million ("May 2017 Common Stock Offering"). The Company used the net proceeds of the May 2017 Common Stock Offering topartially fund the Wilcon Acquisition.81NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)July 2017 Equity OfferingsOn July 26, 2017, the Company completed an offering of 40.15 million shares of common stock, including certain additional shares sold pursuant tothe underwriters' option, which generated net proceeds of approximately $3.8 billion ("July 2017 Common Stock Offering"). The Company used the netproceeds of the July 2017 Common Stock Offering to partially fund the Lightower Acquisition and pay related fees and expenses.On July 26, 2017, the Company completed an offering of 1.65 million shares of the Company's 6.875% Convertible Preferred Stock, at $1,000 per share,including certain additional shares sold pursuant to the underwriters' option, which generated net proceeds of approximately $1.6 billion ("MandatoryConvertible Preferred Stock Offering"). The Company used the net proceeds from the Mandatory Convertible Preferred Stock Offering to partially fund theLightower Acquisition and pay related fees and expenses.The holders of the 6.875% Convertible Preferred Stock are entitled to receive cumulative dividends, when and if declared by the Company's board ofdirectors, at the rate of 6.875% on the liquidation preference of $1,000 per share. The dividends may be paid in cash or, subject to certain limitations, inshares of the Company's common stock or any combination of cash and shares of common stock on February 1, May 1, August 1 and November 1 of eachyear, commencing on November 1, 2017 and to, and including, August 1, 2020. The terms of the 6.875% Convertible Preferred Stock provide that, unlessaccumulated dividends have been paid or set aside for payment on all outstanding shares of 6.875% Convertible Preferred Stock for all past dividend periods,no dividends may be declared or paid on common stock.Unless converted earlier, each outstanding share of the 6.875% Convertible Preferred Stock will automatically convert into shares of the Company'scommon stock on August 1, 2020 into between 8.6806 and 10.4167 shares of the Company's common stock, depending on the applicable market value of thecommon stock and subject to certain anti-dilution adjustments. At any time prior to August 1, 2020, holders of the 6.875% Convertible Preferred Stock mayelect to convert all or a portion of their shares into common stock at the minimum conversion rate of 8.6806, subject to certain anti-dilution adjustments.The July 2017 Common Stock Offering and Mandatory Convertible Preferred Stock Offering are collectively referred to herein as "July 2017 EquityOfferings."Convertible Preferred Stock ConversionIn October and November 2016, all of the approximately 9.8 million shares of the Company's then outstanding 4.50% Convertible Preferred Stockconverted to approximately 11.6 million shares of the Company's common stock at a conversion rate (based on the applicable market value of the commonstock and subject to certain anti-dilutive adjustments) of 1.1880 common shares per each share of 4.50% Convertible Preferred Stock.November 2016 Common Stock OfferingIn November 2016, the Company completed an equity offering of approximately 11.4 million shares of common stock, which generated net proceeds ofapproximately $1.0 billion ("November 2016 Common Stock Offering"). The Company utilized proceeds from such offering to partially fund the FiberNetAcquisition.Declaration and Payment of DividendsDuring the year ended December 31, 2017, the following dividends were declared or paid:Equity Type Declaration Date Record Date Payment Date DividendsPer Share AggregatePaymentAmount(In millions) Common Stock February 17, 2017 March 17, 2017 March 31, 2017 $0.950 $343.3(a) Common Stock May 18, 2017 June 16, 2017 June 30, 2017 $0.950 $350.3(a) Common Stock August 3, 2017 September 15, 2017 September 29, 2017 $0.950 $389.6(a) Common Stock October 15, 2017 December 15, 2017 December 29, 2017 $1.050 $428.8(a) 6.875% Convertible Preferred Stock September 21, 2017 October 15, 2017 November 1, 2017 $18.142 $29.9 6.875% Convertible Preferred Stock December 15, 2017 January 15, 2018 February 1, 2018 $17.188 $28.4 (a)Inclusive of dividends accrued for holders of unvested RSUs, which will be paid when and if the RSUs vest.82NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)See note 19 for further discussion of common stock dividends.Tax Treatment of DividendsThe following table summarizes, for income tax purposes, the nature of dividends paid during 2017 on the Company's common stock and 6.875%Convertible Preferred Stock.Equity Type Payment Date DividendsPer Share OrdinaryTaxableDividend PerShare QualifiedTaxableDividend PerShare(a) Long-TermCapital GainDistribution PerShare Non-TaxableDistribution (pershare)Common Stock March 31, 2017 $0.950 $0.950 $0.347 $— $—Common Stock June 30, 2017 $0.950 $0.950 $0.347 $— $—Common Stock September 29, 2017 $0.950 $0.950 $0.347 $— $—Common Stock December 29, 2017 $1.050 $1.050 $0.384 $— $—6.875% Convertible Preferred Stock November 1, 2017 $18.142 $18.142 $6.629 $— $— (a)Qualified taxable dividend amounts are included in ordinary taxable dividend amounts.The Company has determined that none of the distributions to the Company's shareholders for the tax year ended December 31, 2017 consisted of analternative minimum tax adjustment.Purchases of the Company's Common StockDuring each of the years ended December 31, 2017, 2016 and 2015, the Company purchased 0.3 million shares of common stock utilizing $23.3million, $24.9 million and $29.7 million in cash, respectively.13.Stock-based CompensationStock Compensation PlansPursuant to a stockholder approved plan, the Company has and is permitted to grant stock-based awards to certain employees, consultants or non-employee directors of the Company and its subsidiaries or affiliates. As of December 31, 2017, the Company has 11.2 million shares available for futureissuance pursuant to its 2013 Long-Term Incentive Plan ("LTI Plan"). Of these shares remaining available for future issuance, approximately 3.0 million maybe issued pursuant to outstanding RSUs granted under the LTI Plan.Restricted Stock UnitsThe Company issues RSUs to certain executives and employees; each RSU represents a contingent right to receive one share of common stock subjectto satisfaction of the applicable vesting terms. The RSUs granted to certain executives and employees include (1) annual performance awards that ofteninclude provisions for forfeiture by the employee if certain market performance of the Company's common stock is not achieved, (2) new hire or promotionalawards that generally contain only service conditions, or (3) other awards related to specific business initiatives or compensation objectives includingretention and merger integration. Generally, such awards vest over periods of approximately 3 years.The following is a summary of the RSU activity during the year ended December 31, 2017. RSUs (In thousands)Outstanding at the beginning of year2,677Granted1,359Vested(747)Forfeited(321)Outstanding at end of year2,968The Company granted approximately 1.3 million, 1.3 million and 1.0 million RSUs to the Company's executives and certain other employees for eachof the years ended December 31, 2017, 2016 and 2015, respectively. The weighted-average grant-date83NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)fair value per share of the grants for the years ended December 31, 2017, 2016 and 2015 was $73.52, $68.53 and $69.96 per share, respectively. Theweighted-average requisite service period for the RSUs granted during 2017 was approximately 2.5 years.The approximately 1.3 million RSUs granted during the year ended December 31, 2017, were comprised of (1) approximately 0.7 million RSUs thattime vest over a three-year period and (2) approximately 0.6 million RSUs to the Company's executives and certain other employees which may vest on thethird anniversary of the grant date based upon the Company's total shareholder returns (defined as share price appreciation plus the value of dividends paidduring the performance period) compared to that of selected peer companies. Certain RSU agreements contain provisions that result in forfeiture by theemployee of any unvested shares in the event that the Company's common stock does not achieve certain performance targets. To the extent that the requisiteservice is rendered, compensation cost for accounting purposes is not reversed; rather, it is recognized regardless of whether or not the market performancetarget is achieved.The following table summarizes the assumptions used in the Monte Carlo simulation to determine the grant-date fair value for the awards grantedduring the years ended December 31, 2017, 2016 and 2015, respectively, with market conditions. Years Ended December 31, 2017 2016 2015Risk-free rate1.5% 0.9% 1.0%Expected volatility18% 19% 19%Expected dividend rate4.4% 4.2% 4.2%The Company recognized aggregate stock-based compensation expense related to RSUs of $88.7 million, $76.3 million and $57.1 million for the yearsended December 31, 2017, 2016 and 2015, respectively. The aggregate unrecognized compensation (net of estimated forfeitures) related to RSUs atDecember 31, 2017 is $72.9 million and is estimated to be recognized over a weighted-average period of less than one year.The following table is a summary of the awards vested during the years ended December 31, 2017, 2016 and 2015.Years Ended December 31, Total SharesVested Fair Value onVesting Date (In thousandsof shares) 2017 747 $67,2412016 828 71,3252015 946 83,244Stock-based CompensationThe following table discloses the components of stock-based compensation expense. Years Ended December 31, 2017 2016 2015Stock-based compensation expense: Site rental costs of operations$14,942 $14,371 $8,969Network services and other costs of operations4,961 7,717 5,370General and administrative expenses76,532 74,450 52,809Total stock-based compensation$96,435 $96,538 $67,14884NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)14.Commitments and ContingenciesThe Company is involved in various claims, lawsuits, or proceedings arising in the ordinary course of business. While there are uncertainties inherent inthe ultimate outcome of such matters and it is impossible to presently determine the ultimate costs or losses that may be incurred, if any, managementbelieves the resolution of such uncertainties and the incurrence of such costs should not have a material adverse effect on the Company's consolidatedfinancial position or results of operations. Additionally, the Company and certain of its subsidiaries are contingently liable for commitments or performanceguarantees arising in the ordinary course of business, including certain letters of credit or surety bonds. See note 15 for a discussion of the operating leasecommitments. In addition, see note 1 for a discussion of the Company's option to purchase approximately 53% of its towers at the end of their respectivelease terms. The Company has no obligation to exercise such purchase options.15.Operating LeasesTenant LeasesThe following table is a summary of the rental cash payments owed to the Company, as a lessor, by tenants pursuant to contractual agreements in effectas of December 31, 2017. Generally, the Company's leases with its tenants provide for (1) annual escalations, (2) multiple renewal periods at the tenant'soption, and (3) only limited termination rights at the applicable tenant's option through the current term. As of December 31, 2017, the weighted-averageremaining term of tenant leases is approximately five years, exclusive of renewals at the tenant's option. The tenants' rental payments included in the tablebelow are through the current terms with a maximum current term of 20 years and do not assume exercise of tenant renewal options. Years Ending December 31, 20182019202020212022 Thereafter TotalTenant leases$3,401,845 $3,277,019 $3,160,514 $3,028,825 $2,805,519 $5,628,294 $21,302,016Operating LeasesThe following table is a summary of rental cash payments owed by the Company, as lessee, to landlords pursuant to contractual agreements in effect asof December 31, 2017. The Company is obligated under non-cancelable operating leases for land interests under 76% of its towers. The majority of theselease agreements have (1) certain termination rights that provide for cancellation after a notice period, (2) multiple renewal options at the Company's option,and (3) annual escalations. Lease agreements may also contain provisions for a contingent payment based on revenues or the gross margin derived from thecommunications infrastructure located on the leased land interest. Approximately 75% and approximately 90% of the Company's Towers site rental grossmargins for the year ended December 31, 2017 are derived from towers where the land interest under the tower is owned or leased with final expiration datesof greater than 20 years and ten years, respectively, inclusive of renewals at the Company's option. The operating lease payments included in the table belowinclude payments for certain renewal periods at the Company's option up to the estimated communications infrastructure useful life of 20 years and anestimate of contingent payments based on revenues and gross margins derived from existing tenant leases. Years Ending December 31, 2018 2019 2020 2021 2022 Thereafter TotalOperating leases$635,321 $632,775 $622,587 $617,951 $609,796 $7,941,187 $11,059,617Rental expense from operating leases was $710.2 million, $677.9 million, and $657.1 million, respectively, for the years ended December 31, 2017,2016, and 2015. The rental expense was inclusive of contingent payments based on revenues or gross margin derived from the communications infrastructurelocated on the leased land interests of $100.1 million, $96.9 million, and $91.8 million, respectively, for the years ended December 31, 2017, 2016, and2015.16.Operating Segments and Concentrations of Credit RiskOperating SegmentsAs a result of the 2017 Acquisitions of fiber assets (see note 4), the Company changed the name of the "Small Cells" operating segment to "Fiber." TheCompany changed the name of this segment to reflect its strategy of utilizing the same fiber assets to provide both small cells and fiber solutions to itscustomers. The name change did not impact the composition or previously-reported operating results of the Fiber segment. As such, the Company's operatingsegments are now referred to as "Towers" and "Fiber."85NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)The Towers segment provides access, including space or capacity, to the Company's approximately 40,000 towers geographically dispersed throughoutthe U.S. The Towers segment also reflects certain network services relating to the Company's towers, consisting of site development services and installationservices. The Fiber segment provides access, including space or capacity, to the Company's approximately 60,000 route miles of fiber primarily supportingsmall cells and fiber solutions.The measurement of profit or loss used by the Company's chief operating decision maker ("CODM") to evaluate the results of operations of its operatingsegments are (1) segment site rental gross margin, (2) segment network services and other gross margin and (3) segment operating profit. The Companydefines segment site rental gross margin as segment site rental revenues less segment site rental cost of operations, which excludes stock-based compensationexpense and prepaid lease purchase price adjustments recorded in consolidated cost of operations. The Company defines segment network services and othergross margin as segment network services and other revenues less segment network services and other cost of operations, which excludes stock-basedcompensation expense recorded in consolidated cost of operations. The Company defines segment operating profit as segment site rental gross margin plussegment network services and other gross margin, less general and administrative expenses attributable to the respective segment.Costs that are directly attributable to Towers and Fiber are assigned to those respective segments. The "Other" column (1) represents amounts excludedfrom specific segments, such as restructuring charges (credits), asset write-down charges, acquisition and integration costs, depreciation, amortization andaccretion, amortization of prepaid lease purchase price adjustments, interest expense and amortization of deferred financing costs, gains (losses) on retirementof long-term obligations, net gain (loss) on interest rate swaps, gains (losses) on foreign currency swaps, impairment of available-for-sale securities, interestincome, other income (expense), cumulative effect of a change in accounting principle, income (loss) from discontinued operations, and stock-basedcompensation expense and (2) reconciles segment operating profit to income (loss) before income taxes, as the amounts are not utilized in assessing eachsegment's performance. The "Other" total assets balance includes corporate assets such as cash and cash equivalents which have not been allocated to specificsegments. There are no significant revenues resulting from transactions between the Company's operating segments. Year Ended December 31, 2017 Towers Fiber Other ConsolidatedTotalSegment site rental revenues$2,899,554$769,637 $3,669,191Segment network services and other revenues636,53249,882 686,414Segment revenues3,536,086 819,519 4,355,605Segment site rental cost of operations844,795264,059 1,108,854Segment network services and other cost of operations374,13440,691 414,825Segment cost of operations(a)1,218,929 304,750 1,523,679Segment site rental gross margin2,054,759 505,578 2,560,337Segment network services and other gross margin262,398 9,191 271,589Segment general and administrative expenses(a)93,66289,048167,455 350,165Segment operating profit (loss)2,223,495 425,721 (167,455) 2,481,761Stock-based compensation expense 96,435 96,435Depreciation, amortization and accretion 1,242,408 1,242,408Interest expense and amortization of deferred financing costs 590,682 590,682Other income (expenses) to reconcile to income (loss) from continuing operationsbefore income taxes(b) 81,643 81,643Income (loss) from continuing operations before income taxes $470,593Capital expenditures$418,476 $782,409 $27,186 $1,228,071Total assets (at year end)$17,940,893 $13,669,636 $619,041 $32,229,570Total goodwill (at year end)$5,127,259 $4,894,209 $— $10,021,468 (a)Segment cost of operations excludes (1) stock-based compensation expense of $19.9 million for the year ended December 31, 2017 and (2) prepaid lease purchase priceadjustments of $20.1 million for the year ended December 31, 2017. Segment general and administrative expenses exclude stock-based compensation expense of $76.5 millionfor the year ended December 31, 2017.(b)See consolidated statement of operations for further information.86NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts) Year Ended December 31, 2016 Towers Fiber Other ConsolidatedTotalSegment site rental revenues$2,830,708 $402,599 $3,233,307Segment network services and other revenues603,689 84,229 687,918Segment revenues3,434,397 486,828 3,921,225Segment site rental cost of operations840,209 147,459 987,668Segment network services and other cost of operations344,595 64,859 409,454Segment cost of operations(a)1,184,804 212,318 1,397,122Segment site rental gross margin1,990,499 255,140 2,245,639Segment network services and other gross margin259,094 19,370 278,464Segment general and administrative expenses(a)92,903 60,676 143,001 296,580Segment operating profit (loss)2,156,690 213,834 (143,001) 2,227,523Stock-based compensation expense 96,538 96,538Depreciation, amortization and accretion 1,108,551 1,108,551Interest expense and amortization of deferred financing costs 515,032 515,032Other income (expenses) to reconcile to income (loss) from continuing operationsbefore income taxes(b) 133,548 133,548Income (loss) from continuing operations before income taxes $373,854Capital expenditures$429,526 $409,710 $34,647 $873,883Total assets (at year end)$18,394,572 $3,440,600 $839,920 $22,675,092Total goodwill (at year end)$5,114,639 $643,037 $— $5,757,676 (a)Segment cost of operations excludes (1) stock-based compensation expense of $22.1 million for the year ended December 31, 2016 and (2) prepaid lease purchase priceadjustments of $21.3 million for the year ended December 31, 2016. Segment general and administrative expenses exclude stock-based compensation expense of $74.5 millionfor the year ended December 31, 2016.(b)See consolidated statement of operations for further information. Year Ended December 31, 2015 Towers Fiber Other ConsolidatedTotalSegment site rental revenues$2,734,045 $284,368 $3,018,413Segment network services and other revenues591,655 53,783 645,438Segment revenues3,325,700 338,151 3,663,851Segment site rental cost of operations827,175 107,195 934,370Segment network services and other cost of operations309,025 43,162 352,187Segment cost of operations(a)1,136,200 150,357 1,286,557Segment site rental gross margin1,906,870 177,173 2,084,043Segment network services and other gross margin282,630 10,621 293,251Segment general and administrative expenses(a)91,899 38,379 127,833 258,111Segment operating profit (loss)2,097,601 149,415 (127,833) 2,119,183Stock-based compensation expense 67,148 67,148Depreciation, amortization and accretion 1,036,178 1,036,178Interest expense and amortization of deferred financing costs 527,128 527,128Other income (expenses) to reconcile to income (loss) from continuing operationsbefore income taxes(b) 14,900 14,900Income (loss) from continuing operations before income taxes $473,829Capital expenditures$564,753 $314,882 $29,257 $908,892Total assets (at year end)$17,974,847 $3,511,956 $450,163 $21,936,966Total goodwill (at year end)$4,863,847 $649,704 $— $5,513,551 (a)Segment cost of operations excludes (1) stock-based compensation expense of $14.3 million for the year ended December 31, 2015 and (2) prepaid lease purchase priceadjustments of $20.5 million for the year ended December 31, 2015. Segment general and administrative expenses exclude stock-based compensation expense of $52.8 millionfor the year ended December 31, 2015.(b)See consolidated statement of operations for further information.87NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)Major CustomersThe following table summarizes the percentage of the consolidated revenues for those customers accounting for more than 10% of the consolidatedrevenues. Years Ended December 31, 20172016 2015AT&T25% 27% 27%T-Mobile22% 23% 22%Verizon Wireless22% 22% 21%Sprint17% 16% 19%Total86% 88% 89%Concentrations of Credit RiskFinancial instruments that potentially subject the Company to concentrations of credit risk are primarily cash and cash equivalents, restricted cash andtrade receivables. The Company mitigates its risk with respect to cash and cash equivalents by maintaining such deposits at high credit quality financialinstitutions and monitoring the credit ratings of those institutions. The Company's restricted cash is predominately held and directed by a trustee (see note 2).The Company derives the largest portion of its revenues from customers in the wireless industry. The Company also has a concentration in its volume ofbusiness with AT&T, T-Mobile, Verizon Wireless and Sprint or their agents that accounts for a significant portion of the Company's revenues, receivables anddeferred site rental receivables. The Company mitigates its concentrations of credit risk with respect to trade receivables by actively monitoring thecreditworthiness of its tenants, the use of tenant leases with contractually determinable payment terms or proactive management of past due balances.17.Supplemental Cash Flow InformationThe following table is a summary of the supplemental cash flow information during the years ended December 31, 2017, 2016 and 2015. Years Ended December 31, 201720162015Supplemental disclosure of cash flow information: Interest paid$546,543 $470,655 $489,970Income taxes paid16,427 13,821 28,771Supplemental disclosure of non-cash investing and financing activities: Increase (decrease) in accounts payable for purchases of property and equipment2,279 17,922 (7,042)Purchase of property and equipment under capital leases and installment land purchases31,999 52,322 60,270Installment payment receivable for sale of CCAL (see note 3)— — 117,384Preferred stock dividends accrued but not paid (see note 12)28,359 — 10,99788NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)18.Quarterly Financial Information (Unaudited)Summary quarterly financial information for the years ended December 31, 2017 and 2016 is as follows: Three Months Ended(a) March 31 June 30 September 30 December 312017: Net revenues$1,015,942 $1,038,335 $1,063,238 $1,238,090Operating income (loss)256,549 258,500 260,567 268,429Gains (losses) on retirement of long-term obligations(3,525) — — —Benefit (provision) for income taxes(4,369) (4,538) (2,383) (14,753)Net income (loss) attributable to CCIC stockholders119,138 112,114 115,194 98,104Net income (loss) attributable to CCIC common stockholders, percommon share: Basic$0.33 $0.31 $0.22 $0.17Diluted$0.33 $0.31 $0.21 $0.17 Three Months Ended(a) March 31 June 30 September 30 December 312016: Net revenues$934,384 $962,409 $992,016 $1,032,416Operating income (loss)211,739 231,185 244,254 262,038Gains (losses) on retirement of long-term obligations(30,550) (11,467) (10,274) —Benefit (provision) for income taxes(3,872) (3,884) (5,041) (4,084)Net income (loss) attributable to CCIC stockholders47,840 86,058 98,366 124,709Net income (loss) attributable to CCIC common stockholders, percommon share: Basic$0.11 $0.22 $0.26 $0.35Diluted$0.11 $0.22 $0.26 $0.35 (a)The sum of quarterly information may not agree to year to date information due to rounding.89NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)(Tabular dollars in thousands, except per share amounts)19.Subsequent EventsJanuary 2018 Senior NotesOn January 16, 2018, the Company issued $1.75 billion aggregate principal amount of senior unsecured notes ("January 2018 Senior Notes"), whichconsisted of (1) $750.0 million aggregate principal amount of 3.150% senior unsecured notes due July 2023 ("3.150% Senior Notes") and (2) $1.0 billionaggregate principal amount of 3.800% senior unsecured notes due February 2028 ("3.650% Senior Notes"). The Company used the net proceeds of theJanuary 2018 Senior Notes offering to repay (1) in full the January 2010 Tower Revenue Notes and (2) a portion of the outstanding borrowings under the2016 Revolver.Common Stock DividendOn February 21, 2018, the Company declared a quarterly common stock dividend of $1.05 per share, which was approved by the Company's board ofdirectors. The common stock dividend will be paid on March 30, 2018 to common stockholders of record as of March 16, 2018.90Item 9. Changes in and Disagreements With Accountants on Accounting and Financial DisclosureNone.Item 9A. Controls and Procedures(a) Conclusion Regarding the Effectiveness of Disclosure Controls and ProceduresIn connection with the preparation of this Annual Report on Form 10-K, as of December 31, 2017, the Company's management conducted anevaluation, under the supervision and with the participation of the Company's Chief Executive Officer ("CEO") and Chief Financial Officer ("CFO"), of theeffectiveness of the Company's disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934("Exchange Act")). Based upon their evaluation, the CEO and CFO concluded that the Company's disclosure controls and procedures, as of December 31,2017, were effective to provide reasonable assurance that information required to be disclosed by the Company in the reports filed or submitted by it underthe Exchange Act is recorded, processed, summarized, and reported within the time periods specified in the SEC's rules and forms, and to provide reasonableassurance that information required to be disclosed by the Company in such reports is accumulated and communicated to the Company's management,including its CEO and CFO, as appropriate to allow timely decisions regarding required disclosure.(b) Management's Report on Internal Control Over Financial ReportingManagement is responsible for establishing and maintaining adequate internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) for the Company. Under the supervision and with the participation of the Company's CEO and CFO, management assessed theeffectiveness of the Company's internal control over financial reporting based on the framework described in "Internal Control – Integrated Framework(2013)," issued by the Committee of Sponsoring Organizations of the Treadway Commission. The Company's internal control over financial reporting is aprocess designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for externalpurposes in accordance with U.S. generally accepted accounting principles. The Company's internal control over financial reporting includes those policiesand procedures that:•pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of theCompany;•provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with U.S.generally accepted accounting principles, and that receipts and expenditures of the Company are being made only in accordance withauthorization of management and directors of the Company; and•provide reasonable assurance regarding prevention or timely detection of unauthorized acquisitions, use or disposition of the Company's assetsthat could have a material effect on the financial statements.Management has assessed the effectiveness of the Company's internal control over financial reporting as of December 31, 2017. Based on theCompany's assessment, management has concluded that the Company's internal control over financial reporting was effective as of December 31, 2017 toprovide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external reporting purposes inaccordance with U.S. generally accepted accounting principles. Our evaluation of internal control over financial reporting excluded the internal controls overtotal assets of $3.1 billion and total revenue of $314 million included in our results as of and for the year ended December 31, 2017 related to the operationsof FiberNet, Wilcon and Lightower, which we acquired on January 17, 2017, June 26, 2017 and November 1, 2017, respectively. See note 4 to ourconsolidated financial statements for further discussion of the 2017 Acquisitions. This exclusion is in accordance with the SEC's general guidance that anassessment of the effectiveness of internal control over financial reporting of a recently acquired business may be omitted from management's scope in theyear of acquisition.The effectiveness of the Company's internal control over financial reporting as of December 31, 2017 has been audited by PricewaterhouseCoopersLLP, an independent registered public accounting firm, as stated in their report which appears herein.(c) Changes in Internal Control Over Financial ReportingThere have not been any changes in the Company's internal control over financial reporting (as such term is defined in Rules 13a-15(f) and 15d-15(f) ofthe Exchange Act) during the most recent fiscal quarter that have materially affected or are reasonably likely to materially affect the Company's internalcontrol over financial reporting.91(d) Limitations on the Effectiveness of ControlsBecause of its inherent limitations, the Company's internal control over financial reporting may not prevent or detect misstatements. Also, projectionsof any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that thedegree of compliance with the policies and procedures may deteriorate.Item 9B. Other InformationNone.PART IIIItem 10. Directors and Executive Officers of the RegistrantThe information required to be furnished pursuant to this item will be set forth in the 2018 Proxy Statement and is incorporated herein by reference.Item 11. Executive CompensationThe information required to be furnished pursuant to this item will be set forth in the 2018 Proxy Statement and is incorporated herein by reference.Item 12. Security Ownership of Certain Beneficial Owners and ManagementThe information required to be furnished pursuant to this item will be set forth in the 2018 Proxy Statement and is incorporated herein by reference.The following table summarizes information with respect to equity compensation plans under which equity securities of the registrant are authorized forissuance as of December 31, 2017: Plan category(a)Number of securitiesto be issued uponexercise ofoutstanding options,warrants and rights Weighted-averageexercise price ofoutstanding options,warrants and rights Number of securitiesremaining available forfuture issuance (In shares) (In dollarsper share) (In shares) Equity compensation plans approved by security holders— $— 11,222,154(b) Equity compensation plans not approved by security holders— — — Total— $— 11,222,154 (a)See note 13 to the consolidated financial statements for more detailed information regarding the registrant's equity compensation plan.(b)Of these shares remaining available for future issuance, 3.0 million may be issued pursuant to outstanding RSUs granted under the LTI Plan.Item 13. Certain Relationships and Related TransactionsThe information required to be furnished pursuant to this item will be set forth in the 2018 Proxy Statement and is incorporated herein by reference.Item 14. Principal Accounting Fees and ServicesThe information required to be furnished pursuant to this item will be set forth in the 2018 Proxy Statement and is incorporated herein by reference.92PART IVItem 15. Exhibits, Financial Statement Schedules(a)(1) Financial Statements:The list of financial statements filed as part of this report is submitted as a separate section, the index to which is located on page 48.(a)(2) Financial Statement Schedules:Schedule II—Valuation and Qualifying Accounts.Schedule III—Schedule of Real Estate and Accumulated Depreciation.All other schedules are omitted because they are not applicable or because the required information is contained in the financial statements ornotes thereto included in this Form 10-K.(a)(3) Exhibits:Exhibit Index Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber1.1 Form of Sales Agreement, dated August 28, 2015, between Crown CastleInternational Corp. and each of Merrill Lynch, Pierce, Fenner & SmithIncorporated, Barclays Capital Inc., Citigroup Global Markets Inc., CreditAgricole Securities (USA) Inc., J.P. Morgan Securities LLC, Mizuho SecuritiesUSA Inc., Mitsubishi UFJ Securities (USA), Inc., Morgan Stanley & Co. LLC,RBC Capital Markets, LLC, SMBC Nikko Securities America, Inc., SunTrustRobinson Humphrey, Inc. and Wells Fargo Securities, LLC 8-K 001-16441 August 28,2015 1.12.1 Agreement and Plan of Merger by and between Crown Castle International Corp.and Crown Castle REIT Inc., dated September 19, 2014 8-K 001-16441 September 23,2014 2.12.2 Agreement and Plan of Merger, dated as of July 18, 2017, by and among CrownCastle International Corp., LTS Group Holdings, LLC, Berkshire Fund VII-A(LTS) Acquisition Partners, Berkshire Fund VIII-A (LTS) Acquisition Partners,LTS Berkshire Fund VII-A Blocker Corporation, LTS Berkshire Fund VIII-ABlocker Corporation, LTS Co-Invest Blocker LLC, LTS Co-Invest Blocker IILLC, LTS Rollover Blocker LLC, LTS BF VII-A Blocker Merger Sub, Inc., LTSBF VIII-A Blocker Merger Sub, Inc., LTS Co-Invest Blocker Merger Sub, Inc.,LTS Co-Invest Blocker II Merger Sub, Inc., LTS Rollover Blocker Merger Sub,Inc., LTS Group Holdings Merger Sub, Inc. and BSR LLC, as equityholders’representative 8-K 001-16441 July 19, 2017 2.13.1 Restated Certificate of Incorporation of Crown Castle International Corp., datedJuly 20, 2017 8-K 001-16441 July 26, 2017 3.13.2 Certificate of Designations of 6.875% Mandatory Convertible Preferred Stock,Series A, of Crown Castle International Corp., filed with the Secretary of State ofthe State of Delaware and effective July 26, 2017 8-K 001-16441 July 26, 2017 3.23.3 Amended and Restated By-Laws of Crown Castle International Corp. datedDecember 15, 2017 8-K 001-16441 December 15,2017 3.14.1 Specimen of Common Stock Certificate 8-K 001-16441 December 16,2014 4.24.2 Specimen Certificate of 6.875% Mandatory Convertible Preferred Stock, Series A(included as Exhibit A to Exhibit 3.2) 8-K 001-16441 July 26, 2017 3.293 Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber4.3 Indenture, dated as of June 1, 2005, relating to the Senior Secured TowerRevenue Notes, by and among JPMorgan Chase Bank, N.A., as Indenture Trustee,and Crown Castle Towers LLC, Crown Castle South LLC, CrownCommunications Inc., Crown Castle PT Inc., Crown Communication New York,Inc. and Crown Castle International Corp. de Puerto Rico, collectively as Issuers 8-K 001-16441 June 9, 2005 4.14.4 Indenture Supplement, dated as of August 16, 2010, by and among The Bank ofNew York Mellon (as successor to The Bank of New York as successor toJPMorgan Chase Bank, N.A.), as Indenture Trustee, and Crown Castle TowersLLC, Crown Castle South LLC, Crown Communication Inc., Crown Castle PTInc., Crown Communication New York, Inc., Crown Castle International Corp. dePuerto Rico, Crown Castle Towers 05 LLC, Crown Castle PR LLC, Crown CastleMU LLC and Crown Castle MUPA LLC, collectively as Issuers, relating to theSenior Secured Tower Revenue Notes, Series 2010-6 8-K 001-16441 August 26,2010 4.34.5 Indenture Supplement, dated as of June 30, 2014, by and among The Bank ofNew York Mellon (as successor to The Bank of New York as successor toJPMorgan Chase Bank, N.A.), as Indenture Trustee, and Crown Castle TowersLLC, Crown Castle South LLC, Crown Communication LLC, Crown Castle PTInc., Crown Communication New York, Inc., Crown Castle International Corp. dePuerto Rico, Crown Castle Towers 05 LLC, Crown Castle PR LLC, Crown CastleMU LLC and Crown Castle MUPA LLC 8-K 001-16441 July 1, 2014 4.14.6 Indenture Supplement, dated as of May 15, 2015, by and among The Bank ofNew York Mellon (as successor to The Bank of New York as successor toJPMorgan Chase Bank, N.A.), as Indenture Trustee, and Crown Castle TowersLLC, Crown Castle South LLC, Crown Communication LLC, Crown CastleTowers 05 LLC, Crown Castle PR LLC, Crown Castle MU LLC and CrownCastle MUPA LLC, collectively as Issuers, relating to the Senior Secured TowerRevenue Notes, Series 2015-1 8-K 001-16441 May 21, 2015 4.14.7 Indenture Supplement, dated as of May 15, 2015, by and among The Bank ofNew York Mellon (as successor to The Bank of New York as successor toJPMorgan Chase Bank, N.A.), as Indenture Trustee, and Crown Castle TowersLLC, Crown Castle South LLC, Crown Communication LLC, Crown CastleTowers 05 LLC, Crown Castle PR LLC, Crown Castle MU LLC and CrownCastle MUPA LLC, collectively as Issuers, relating to the Senior Secured TowerRevenue Notes, Series 2015-2 8-K 001-16441 May 21, 2015 4.24.8 Indenture dated July 31, 2009, between Pinnacle Towers Acquisition HoldingsLLC, GS Savings Inc., GoldenState Towers, LLC, Pinnacle Towers AcquisitionLLC, Tower Ventures III, LLC and TVHT, LLC, as Issuers, Global SignalHoldings III, LLC, as Guarantor, and The Bank of New York Mellon TrustCompany, N.A., as Indenture Trustee, relating to Senior Secured Notes 8-K 001-16441 August 4, 2009 4.14.9 Indenture Supplement dated July 31, 2009, between Pinnacle TowersAcquisition Holdings LLC, GS Savings Inc., GoldenState Towers, LLC, PinnacleTowers Acquisition LLC, Tower Ventures III, LLC and TVHT, LLC, as Issuers,Global Signal Holdings III, LLC, as Guarantor, and The Bank of New YorkMellon Trust Company, N.A., as Indenture Trustee, relating to Senior SecuredNotes, Series 2009-1 8-K 001-16441 August 4, 2009 4.24.10 Indenture dated as of October 15, 2012, between Crown Castle InternationalCorp. and The Bank of New York Mellon Trust Company, N.A., as Trustee,relating to 5.25% Senior Notes due 2023 8-K 001-16441 October 16,2012 4.194 Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber4.11 First Supplemental Indenture dated as of December 15, 2014, among CrownCastle REIT Inc., Crown Castle International Corp. and The Bank of New YorkMellon Trust Company, N.A., as Trustee, relating to 5.25% Senior Notes due2023 8-K 001-16441 December 16,2014 4.44.12 Indenture dated as of December 24, 2012, by and among CC Holdings GS VLLC, Crown Castle GS III Corp., each of the guarantors party thereto and TheBank of New York Mellon Trust Company, N.A., as Trustee, relating to the3.849% Senior Secured Notes due 2023 8-K 001-16441 December 28,2012 4.14.13 Indenture dated April 15, 2014, between Crown Castle International Corp. andThe Bank of New York Mellon Trust Company, N.A., as trustee 8-K 001-16441 April 15, 2014 4.14.14 First Supplemental Indenture dated April 15, 2014, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, relating to 4.875% Senior Notes due 2022 8-K 001-16441 April 15, 2014 4.24.15 Second Supplemental Indenture dated December 15, 2014, between CrownCastle REIT Inc., Crown Castle International Corp. and The Bank of New YorkMellon Trust Company, N.A., as trustee 8-K 001-16441 December 16,2014 4.54.16 Third Supplemental Indenture dated December 15, 2014, between Crown CastleREIT Inc., Crown Castle International Corp. and The Bank of New York MellonTrust Company, N.A., as trustee 8-K 001-16441 December 16,2014 4.64.17 Fourth Supplemental Indenture dated February 8, 2016 between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, to the Indenture dated April 15, 2014, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, relating to 3.400% Senior Notes due 2021 and 4.450% Senior Notes due2026 8-K 001-16441 February 8,2016 4.14.18 Fifth Supplemental Indenture dated May 6, 2016, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, to the Indenture dated April 15, 2014, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, relating to 3.400% Senior Notes due 2021 and 3.700% Senior Notes due2026 8-K 001-16441 May 6, 2016 4.14.19 Sixth Supplemental Indenture dated September 1, 2016, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, to the Indenture dated April 15, 2014, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, relating to 2.250% Senior Notes due 2021 8-K 001-16441 September 1,2016 4.14.20 Seventh Supplemental Indenture dated February 2, 2017, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, to the Indenture dated April 15, 2014, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, relating to 4.000% Senior Notes due 2027 8-K 001-16441 February 2,2017 4.14.21 Eighth Supplemental Indenture dated May 1, 2017, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, to the Indenture dated April 15, 2014, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, relating to 4.750% Senior Notes due 2047 8-K 001-16441 May 1, 2017 4.195 Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber4.22 Ninth Supplemental Indenture dated August 1, 2017, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, to the Indenture dated April 15, 2014, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, relating to 3.200% Senior Notes due 2024 and 3.650% Senior Notes due2027 8-K 001-16441 August 1, 2017 4.14.23 Tenth Supplemental Indenture dated January 16, 2018, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee, to the Indenture dated April 15, 2014, between Crown CastleInternational Corp. and The Bank of New York Mellon Trust Company, N.A., astrustee 8-K 001-16441 January 17,2018 4.110.1† Amended and Restated Severance Agreement between Crown CastleInternational Corp. and Jay A. Brown, effective as of June 1, 2016 8-K 001-16441 February 24,2016 10.310.2† Amended and Restated Severance Agreement between Crown CastleInternational Corp. and W. Benjamin Moreland, effective as of June 1, 2016 8-K 001-16441 February 24,2016 10.410.3† Form of Severance Agreement between Crown Castle International Corp. andPhilip M. Kelley 8-K 001-16441 July 15, 2008 10.110.4† Form of Severance Agreement between Crown Castle International Corp. andJames D. Young 8-K 001-16441 March 2, 2005 10.410.5† Form of First Amendment to Severance Agreement between Crown CastleInternational Corp and certain senior officers, including James D. Young 8-K 001-16441 December 7,2007 10.210.6† Form of Amendment to Severance Agreement between Crown CastleInternational Corp. and certain senior officers, including James D. Young andPhilip M. Kelley, effective April 6, 2009 8-K 001-16441 April 8, 2009 10.210.7† Form of Amendment to Severance Agreement between Crown CastleInternational Corp. and certain executive officers, including James D. Young andPhilip M. Kelley 8-K 001-16441 February 24,2016 10.510.8† Form of Severance Agreement between Crown Castle International Corp. andeach of Kenneth J. Simon, Daniel K. Schlanger, Michael J. Kavanagh and RobertC. Ackerman 10-K 001-16441 February 22,2016 10.4710.9† Crown Castle International Corp. 2013 Long-Term Incentive Plan DEF14A 001-16441 April 8, 2013 App. A10.10† First Amendment to Crown Castle International Corp. 2013 Long-Term IncentivePlan, as amended 10-Q 001-16441 August 4, 2016 10.110.11† Form of 2013 Long-Term Incentive Plan Restricted Stock Units Agreement(effective as of February 20, 2014) 8-K 001-16441 February 26,2014 10.210.12† Form of 2013 Long-Term Incentive Plan Restricted Stock Units Agreement(effective as of February 18, 2016) 8-K 001-16441 February 24,2016 10.210.13† Form of 2013 Long-Term Incentive Plan Restricted Stock Units Agreement(effective as of August 3, 2017) 10-Q 001-16441 August 7, 2017 10.110.14† Crown Castle International Corp. Extended Service Separation Program 8-K 001-16441 November 7,2016 10.110.15† Crown Castle International Corp. 2017 Executive Management Team AnnualIncentive Plan 8-K 001-16441 February 23,2017 10.110.16† Crown Castle International Corp. Summary of Non-Employee DirectorCompensation 8-K 001-16441 February 23,2017 10.210.17 Formation Agreement, dated December 8, 1998, relating to the formation ofCrown Atlantic Company LLC, Crown Atlantic Holding Sub LLC, and CrownAtlantic Holding Company LLC 8-K 000-24737 December 10,1998 99.396 Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber10.18 Amendment Number 1 to Formation Agreement, dated March 31, 1999, by andamong Crown Castle International Corp., Cellco Partnership, certain TransferringPartnerships (as defined therein) and CCA Investment Corp. 8-K 000-24737 April 12, 1999 2.210.19 Crown Atlantic Holding Company LLC Amended and Restated OperatingAgreement, dated May 1, 2003, by and between Bell Atlantic Mobile, Inc. andCCA Investment Corp. 10-K 001-16441 March 10, 2004 2.310.20 Global Lease Agreement dated March 31, 1999 between Crown AtlanticCompany, LLC and Cellco Partnership 8-K 000-24737 April 12, 1999 99.610.21 Crown Atlantic Company LLC Operating Agreement entered into as of March31, 1999 by and between Cellco Partnerships and Crown Atlantic Holding SubLLC 8-K 000-24737 April 12, 1999 99.110.22 Crown Atlantic Company LLC First Amendment to Operating Agreement, datedMay 1, 2003, by Crown Atlantic Company LLC, and each of Bell AtlanticMobile Inc. and Crown Atlantic Holding Sub LLC 10-K 001-16441 March 10, 2004 2.510.23 Agreement to Sublease dated June 1, 1999 by and among BellSouth MobilityInc., BellSouth Telecommunications Inc., the Transferring Entities (as definedtherein), Crown Castle International Corp. and Crown Castle South Inc. 8-K 000-24737 June 9, 1999 99.110.24 Sublease dated June 1, 1999 by and among BellSouth Mobility Inc., CertainBMI Affiliates, Crown Castle International Corp. and Crown Castle South Inc. 8-K 000-24737 June 9, 1999 99.310.25 Agreement to Sublease dated August 1, 1999 by and among BellSouth PersonalCommunications, Inc., BellSouth Carolinas PCS, L.P., Crown CastleInternational Corp. and Crown Castle South Inc. 10-K 000-24737 March 30, 2000 2.710.26 Sublease dated August 1, 1999 by and among BellSouth PersonalCommunications, Inc., BellSouth Carolinas PCS, L.P., Crown CastleInternational Corp. and Crown Castle South Inc. 10-K 000-24737 March 30, 2000 2.810.27 Formation Agreement dated November 7, 1999 relating to the formation ofCrown Castle GT Company LLC, Crown Castle GT Holding Sub LLC and CrownCastle GT Holding Company LLC 8-K 000-24737 November 12,1999 99.210.28 Operating Agreement, dated January 31, 2000 by and between Crown Castle GTCorp. and affiliates of GTE Wireless Incorporated 10-K 000-24737 March 30, 2000 2.1110.29 Management Agreement, dated as of June 8, 2005, by and among Crown CastleUSA Inc., as Manager, and Crown Castle Towers LLC, Crown Castle South LLC,Crown Communication Inc., Crown Castle PT Inc., Crown Communication NewYork, Inc., Crown Castle International Corp. de Puerto Rico, Crown Castle GTHolding Sub LLC and Crown Castle Atlantic LLC, collectively as Owners 8-K 001-16441 June 9, 2005 10.110.30 Series 2005-1 Management Agreement Amendment, dated September 26, 2006,by and among Crown Castle USA Inc., as Manager, and Crown Castle TowersLLC, Crown Castle South LLC, Crown Communication Inc., Crown Castle PTInc., Crown Communication New York, Inc., Crown Castle International Corp. dePuerto Rico, Crown Castle GT Holding Sub LLC and Crown Castle AtlanticLLC, collectively, as Owners 8-K 001-16441 September 29,2006 10.297 Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber10.31 Joinder and Amendment to Management Agreement, dated as of November 29,2006, by and among Crown Castle USA Inc., as Manager, and Crown CastleTowers LLC, Crown Castle South LLC, Crown Communication Inc., CrownCastle PT Inc., Crown Communication New York, Inc., Crown CastleInternational Corp. de Puerto Rico, Crown Castle Towers 05 LLC, Crown CastlePR LLC, Crown Castle MU LLC, Crown Castle MUPA LLC, Crown Castle GTHolding Sub LLC and Crown Castle Atlantic LLC, collectively as Owners 8-K 001-16441 December 5,2006 10.110.32 Cash Management Agreement, dated as of June 8, 2005, by and among CrownCastle Towers LLC, Crown Castle South LLC, Crown Communication Inc.,Crown Castle PT Inc., Crown Communication New York, Inc. and Crown CastleInternational Corp. de Puerto Rico, as Issuers, JPMorgan Chase Bank, N.A., asIndenture Trustee, Crown Castle USA Inc., as Manager, Crown Castle GTHolding Sub LLC, as Member of Crown Castle GT Company LLC, and CrownCastle Atlantic LLC, as Member of Crown Atlantic Company LLC 8-K 001-16441 June 9, 2005 10.210.33 Joinder to Cash Management Agreement, dated as of November 29, 2006, by andamong Crown Castle Towers LLC, Crown Castle South LLC, CrownCommunication Inc., Crown Castle PT Inc., Crown Communication New York,Inc. and Crown Castle International Corp. de Puerto Rico, Crown Castle Towers05 LLC, Crown Castle PR LLC, Crown Castle MU LLC, Crown Castle MUPALLC, as Issuers, The Bank of New York (as successor to JPMorgan Chase Bank,N.A.), as Indenture Trustee, Crown Castle USA Inc., as Manager, Crown CastleGT Holding Sub LLC, as Member of Crown Castle GT Company LLC, andCrown Castle Atlantic LLC, as Member of Crown Atlantic Company LLC 8-K 001-16441 December 5,2006 10.210.34 Servicing Agreement, dated as of June 8, 2005, by and among Midland LoanServices, Inc., as Servicer, and JPMorgan Chase Bank, N.A., as Indenture Trustee 8-K 001-16441 June 9, 2005 10.310.35 Agreement to Contribute, Lease and Sublease, dated as of February 14, 2005among Sprint Corporation, the Sprint subsidiaries named therein and GlobalSignal Inc. 8-K 001-32168 February 17,2005 10.110.36 Master Lease and Sublease, dated as of May 26, 2005, by and among STC OneLLC, as lessor, Sprint Telephony PCS L.P., as Sprint Collocator, Global SignalAcquisitions II LLC, as lessee, and Global Signal Inc. 8-K 001-32168 May 27, 2005 10.110.37 Master Lease and Sublease, dated as of May 26, 2005, by and among STC TwoLLC, as lessor, SprintCom, Inc., as Sprint Collocator, Global Signal AcquisitionsII LLC, as lessee, and Global Signal Inc. 8-K 001-32168 May 27, 2005 10.210.38 Master Lease and Sublease, dated as of May 26, 2005, by and among STC ThreeLLC, as lessor, American PCS Communications, LLC, as Sprint Collocator,Global Signal Acquisitions II LLC, as lessee, and Global Signal Inc. 8-K 001-32168 May 27, 2005 10.310.39 Master Lease and Sublease, dated as of May 26, 2005, by and among STC FourLLC, as lessor, PhillieCo, L.P., as Sprint Collocator, Global Signal Acquisitions IILLC, as lessee, and Global Signal Inc. 8-K 001-32168 May 27, 2005 10.410.40 Master Lease and Sublease, dated as of May 26, 2005, by and among STC FiveLLC, as lessor, Sprint Spectrum L.P., as Sprint Collocator, Global SignalAcquisitions II LLC, as lessee, and Global Signal Inc. 8-K 001-32168 May 27, 2005 10.510.41 Master Lease and Sublease, dated as of May 26, 2005, by and among STC SixCompany, Sprint Spectrum L.P., as Sprint Collocator, Global Signal AcquisitionsII LLC, as lessee, and Global Signal Inc. 8-K 001-32168 May 27, 2005 10.698 Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber10.42 Management Agreement, dated as of July 31, 2009, by and among Crown CastleUSA Inc., as Manager, and Pinnacle Towers Acquisition Holdings LLC, and thedirect and indirect subsidiaries of Pinnacle Towers Acquisition Holdings LLC,collectively, as Owners 8-K 001-16441 August 4, 2009 10.110.43 Cash Management Agreement, dated as of July 31, 2009, by and among PinnacleTowers Acquisition Holdings LLC, Pinnacle Towers Acquisition LLC, GSSavings Inc., GoldenState Towers, LLC, Tower Ventures III, LLC and TVHT,LLC, as Issuers, The Bank of New York Mellon Trust Company, N.A., asIndenture Trustee, and Crown Castle USA Inc., as Manager 8-K 001-16441 August 4, 2009 10.210.44 Servicing Agreement, dated as of July 31, 2009, by and among Midland LoanServices, Inc., as Servicer, and The Bank of New York Mellon Trust Company,N.A., as Indenture Trustee 8-K 001-16441 August 4, 2009 10.310.45 Master Agreement dated as of September 28, 2012, among T-Mobile USA, Inc.,SunCom Wireless Operating Company, L.L.C., Cook Inlet/VS GSM IV PCSHoldings, LLC, T-Mobile Central LLC, T-Mobile South LLC,Powertel/Memphis, Inc., VoiceStream Pittsburgh, L.P., T-Mobile West LLC, T-Mobile Northeast LLC, Wireless Alliance, LLC, SunCom Wireless PropertyCompany, L.L.C. and Crown Castle International Corp. 8-K 001-16441 October 2, 2012 10.110.46 Management Agreement, dated as of December 24, 2012, by and among CrownCastle USA Inc., as Manager, and CC Holdings GS V LLC, Global SignalAcquisitions LLC, Global Signal Acquisitions II LLC, Pinnacle Towers LLC andthe direct and indirect subsidiaries of Pinnacle Towers LLC, collectively, asOwners 8-K 001-16441 December 28,2012 10.110.47 Master Prepaid Lease, dated as of November 30, 2012, by and among T-MobileUSA Tower LLC, T-Mobile West Tower LLC, T-Mobile USA, Inc. and CCTMOLLC 10-K 001-16441 February 12,2013 10.4010.48 MPL Site Master Lease Agreement, dated as of November 30, 2012, by andamong T-Mobile Central LLC, T-Mobile South LLC, Powertel/Memphis, Inc.,VoiceStream Pittsburgh, L.P., T-Mobile West LLC, T-Mobile Northeast LLC,Wireless Alliance, LLC, SunCom Wireless Operating Company, L.L.C., T-MobileUSA, Inc. and CCTMO LLC 10-K 001-16441 February 12,2013 10.4110.49 Sale Site Master Lease Agreement, dated as of November 30, 2012, by andamong T-Mobile Central LLC, T-Mobile South LLC, Powertel/Memphis, Inc.,VoiceStream Pittsburgh, L.P., T-Mobile West LLC, T-Mobile Northeast LLC,Wireless Alliance, LLC, SunCom Wireless Operating Company, L.L.C., T-MobileUSA, Inc., T3 Tower 1 LLC and T3 Tower 2 LLC 10-K 001-16441 February 12,2013 10.4210.50 Management Agreement, dated as of November 30, 2012, by and amongSunCom Wireless Operating Company, L.L.C., Cook Inlet/VS GSM IV PCSHoldings, LLC, T-Mobile Central LLC, T-Mobile South LLC,Powertel/Memphis, Inc., VoiceStream Pittsburgh, L.P., T-Mobile West LLC, T-Mobile Northeast LLC, Wireless Alliance, LLC, SunCom Wireless PropertyCompany, L.L.C., T-Mobile USA Tower LLC, T-Mobile West Tower LLC,CCTMO LLC, T3 Tower 1 LLC and T3 Tower 2 LLC 10-K 001-16441 February 12,2013 10.4310.51 Master Agreement dated as of October 18, 2013, among AT&T Inc. and CrownCastle International Corp. 8-K 001-16441 October 21,2013 10.110.52 Master Prepaid Lease, dated as of December 16, 2013, by and among CCATTLLC, AT&T Mobility LLC and the AT&T Lessors party thereto 10-K 001-16441 February 24,2014 10.4910.53 MPL Site Master Lease Agreement, dated as of December 16, 2013, by andamong CCATT LLC, AT&T Mobility LLC and the AT&T Collocators partythereto 10-K 001-16441 February 24,2014 10.5099 Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber10.54 Sale Site Master Lease Agreement, dated as of December 16, 2013, by and amongAT&T Mobility LLC, the AT&T Collocators party thereto and the TowerOperators party thereto 10-K 001-16441 February 24,2014 10.5110.55 Management Agreement, dated as of December 16, 2013, by and among CCATTLLC, the Sale Site Subsidiaries party thereto, the AT&T Newcos party theretoand the AT&T Contributors party thereto 10-K 001-16441 February 24,2014 10.5210.56 Stock Purchase Agreement, dated as of April 29, 2015, by and among QuantaServices, Inc., Crown Castle International Corp. and CC SCN Fiber LLC 10-Q 001-16441 May 8, 2015 10.510.57 Agreement for the Sale and Purchase of the Shares of Crown Castle AustraliaHoldings Pty Ltd, dated May 14, 2015, by and among Crown CastleInternational Corp., Crown Castle Operating LLC, The Trust Company(Nominees) Limited, Todd International Investments Limited, Oceania CapitalLimited, Birdsong Capital Limited, Baytown Investments Limited, Heritage PTCLLC, David Lloyd CCA Limited, Turri Finance Pty Ltd and Turri Bidco Pty Ltd 10-Q 001-16441 August 7, 2015 10.210.58 Credit Agreement dated as of January 21, 2016, among Crown CastleInternational Corp., the lenders and issuing banks party thereto and JPMorganChase Bank, N.A., as administrative agent 8-K 001-16441 January 22,2016 10.110.59 Amendment No. 1 dated as of February 13, 2017, among Crown CastleInternational Corp., the lenders and issuing banks party thereto, and JPMorganChase Bank, N.A., as administrative agent, to the Credit Agreement dated as ofJanuary 21, 2016, by and among Crown Castle International Corp., the lendersand issuing banks from time to time party thereto and JPMorgan Chase Bank,N.A., as administrative agent. 8-K 001-16441 February 13,2017 10.110.60 Amendment No. 2 dated as of August 29, 2017, among Crown CastleInternational Corp., the lenders and issuing banks party thereto, and JPMorganChase Bank, N.A., as administrative agent, to the Credit Agreement dated as ofJanuary 21, 2016, by and among Crown Castle International Corp., the lendersand issuing banks from time to time party thereto and JPMorgan Chase Bank,N.A., as administrative agent 8-K 001-16441 August 29,2017 10.112* Computation of Ratios of Earnings to Fixed Charges and Earnings to CombinedFixed Charges and Preferred Stock Dividends — — — —21* Schedule of Subsidiaries of Crown Castle International Corp. — — — —23* Consent of PricewaterhouseCoopers LLP — — — —24* Power of Attorney (included on signature page of this annual report) — — — —31.1* Certification of Chief Executive Officer pursuant to Section 302 of Sarbanes-Oxley Act of 2002 — — — —31.2* Certification of Chief Financial Officer pursuant to Section 302 of Sarbanes-Oxley Act of 2002 — — — —32.1** Certification of Chief Executive Officer and Chief Financial Officer pursuant toSection 906 of Sarbanes-Oxley Act of 2002 — — — —101.INS* XBRL Instance Document — — — —101.SCH* XBRL Taxonomy Extension Schema Document — — — —101.DEF* XBRL Taxonomy Extension Definition Linkbase — — — —101.CAL* XBRL Taxonomy Extension Calculation Linkbase Document — — — —100 Incorporated by ReferenceExhibitNumber Exhibit Description Form File Number Date of Filing ExhibitNumber101.LAB* XBRL Taxonomy Extension Label Linkbase Document — — — —101.PRE* XBRL Taxonomy Extension Presentation Linkbase Document — — — — * Filed herewith.** Furnished herewith.† Indicates management contract or compensatory plan or arrangement.Item 16. Form 10-K SummaryN/A101CROWN CASTLE INTERNATIONAL CORP. AND SUBSIDIARIESSCHEDULE II—VALUATION AND QUALIFYING ACCOUNTSYEARS ENDED DECEMBER 31, 2017, 2016 AND 2015(In thousands of dollars) Additions Deductions Balance atBeginningof Year Charged toOperations Credited toOperations Written Off Effect ofExchange RateChanges Other Adjustments Balance atEnd ofYearAllowance for DoubtfulAccounts Receivable: 2017$11,314 $4,360 $— $(4,591) $— $2,663(a) $13,7462016$9,574 $4,873 $— $(3,133) $— $— $11,3142015$10,037 $2,958 $— $(3,421) $— $— $9,574 (a)Represents the allowance for doubtful accounts reflected in the preliminary purchase price allocations for the 2017 Acquisitions. See note 4. Additions Deductions Balance atBeginningof Year ChargedtoOperations Charged toAdditionalPaid-in Capitaland OtherComprehensiveIncome Credited toOperations Credited toAdditionalPaid-in Capitaland OtherComprehensiveIncome OtherAdjustments(a) Balance atEnd ofYearDeferred Tax ValuationAllowance: 2017$6,627 $59 $— $(5,514) $— $— $1,1722016$1,994 $586 $— $(2,236) $— $6,283 $6,6272015$21,038 $164 $— $(3,000) $— $(16,208) $1,994 (a)Inclusive of (1) the effects of acquisitions and (2) the inclusion of small cells in the REIT in January 2016.102CROWN CASTLE INTERNATIONAL CORP. AND SUBSIDIARIESSCHEDULE III—SCHEDULE OF REAL ESTATE AND ACCUMULATED DEPRECIATIONYEARS ENDED DECEMBER 31, 2017 AND 2016(In thousands of dollars)DescriptionEncumbrances Initial Cost toCompanyCost CapitalizedSubsequent toAcquisitionGross AmountCarried at Close ofCurrent Period AccumulatedDepreciation at Closeof Current PeriodDate ofConstructionDate AcquiredLife on WhichDepreciation in LatestIncome Statement isComputed40,080 towers(1)$4,580,581(2) (3) (3) $20,109,562(4) $(7,303,230)VariousVariousUp to 20 years (1)Amount is exclusive of small cell nodes. No single tower exceeds 5% of the aggregate gross amounts at which the assets were carried at the close of the period set forth in the tableabove.(2)Certain of the Company's debt is secured by (1) a pledge of the equity interests in each applicable issuer and (2) a security interest in the applicable issuers' leases with tenants tolease tower space (space licenses).(3)The Company has omitted this information, as it would be impracticable to compile such information on a tower-by-tower basis.(4)Does not include those towers under construction. 2017 2016Gross amount at beginning$16,120,896 $15,110,835Additions during period: Acquisitions through foreclosure— —Other acquisitions(1)(2)2,787,829 130,139Communications infrastructure construction and improvements1,062,589 709,538Purchase of land interests80,647 74,579Sustaining capital expenditures56,480 55,417Other(3)46,537 95,049Total additions4,034,082 1,064,722Deductions during period: Cost of real estate sold or disposed(45,416) (54,661)Other— —Total deductions:(45,416) (54,661)Balance at end$20,109,562 $16,120,896 (1)Inclusive of changes between the final purchase price allocation and the preliminary purchase price allocations.(2)Includes acquisitions of communications infrastructure.(3)Predominately relates to the purchase of property and equipment under capital leases and installment land purchases. 2017 2016Gross amount of accumulated depreciation at beginning$(6,446,448) $(5,648,598)Additions during period: Depreciation(889,983) (810,549)Total additions(889,983) (810,549)Deductions during period: Amount for assets sold or disposed26,391 24,190Other6,810 (11,491)Total deductions33,201 12,699Balance at end$(7,303,230) $(6,446,448)103SIGNATURESPursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this AnnualReport on Form 10-K to be signed on its behalf by the undersigned, thereunto duly authorized, on this 26th day of February, 2018. CROWN CASTLE INTERNATIONAL CORP. By: /s/ DANIEL K. SCHLANGER Daniel K. SchlangerSenior Vice President, Chief Financial Officer and TreasurerPOWER OF ATTORNEYKNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Jay A. Brown and Kenneth J.Simon and each of them, as his or her true and lawful attorneys-in-fact and agents with full power of substitution and re-substitution for him or her and in hisor her name, place and stead, in any and all capacities, to sign any and all documents relating to the Annual Report on Form 10-K, including any and allamendments and supplements thereto, for the year ended December 31, 2017 and to file the same with all exhibits thereto and other documents in connectiontherewith with the Securities and Exchange Commission granting unto said attorneys-in-fact and agents full power and authority to do and perform each andevery act and thing requisite and necessary to be done in and about the premises, as fully as to all intents and purposes as he or she might or could do inperson, hereby ratifying and confirming all that said attorneys-in-fact and agents or their substitute or substitutes may lawfully do or cause to be done byvirtue hereof.Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended, this Annual Report on Form 10-K has beensigned below by the following persons on behalf of the Registrant and in the capacities indicated below on this 26th day of February, 2018.104Name Title /s/ JAY A. BROWN President, Chief Executive Officer and DirectorJay A. Brown (Principal Executive Officer) /s/ DANIEL K. SCHLANGER Senior Vice President, Chief Financial Officer and TreasurerDaniel K. Schlanger (Principal Financial Officer) /s/ ROBERT S. COLLINS Vice President and ControllerRobert S. Collins (Principal Accounting Officer) /s/ J. LANDIS MARTIN Chairman of the Board of DirectorsJ. Landis Martin /s/ P. ROBERT BARTOLO DirectorP. Robert Bartolo /s/ CINDY CHRISTY DirectorCindy Christy /s/ ARI Q. FITZGERALD DirectorAri Q. Fitzgerald /s/ ROBERT E. GARRISON II DirectorRobert E. Garrison II /s/ ANDREA J. GOLDSMITH DirectorAndrea J. Goldsmith /s/ LEE W. HOGAN DirectorLee W. Hogan /s/ EDWARD C. HUTCHESON, JR. DirectorEdward C. Hutcheson, Jr. /s/ ROBERT F. MCKENZIE DirectorRobert F. McKenzie /s/ ANTHONY J. MELONE DirectorAnthony J. Melone /s/ W. BENJAMIN MORELAND DirectorW. Benjamin Moreland 105EXHIBIT 12CROWN CASTLE INTERNATIONAL CORP.COMPUTATION OF RATIOS OF EARNINGS TO FIXED CHARGES ANDEARNINGS TO COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS(DOLLARS IN THOUSANDS) Years Ended December 31, 2017 2016 2015 2014 2013Computation of earnings: Income (loss) from continuing operations before income taxes$470,593 $373,854 $473,829 $335,070 $251,001Add: Fixed charges (as computed below)838,966 748,001 750,968 791,386 752,241Subtract: Interest capitalized(11,545) (7,010) (4,805) (2,985) (1,832) $1,298,014 $1,114,845 $1,219,992 $1,123,471 $1,001,410Computation of fixed charges and combined fixed charges andpreferred stock dividends and losses on purchases of preferredstock: Interest expense$571,647 $495,945 $487,355 $491,581 $491,041Amortized premiums, discounts and capitalized expensesrelated to indebtedness19,035 19,087 39,773 81,710 98,589Interest capitalized11,545 7,010 4,805 2,985 1,832Interest component of operating lease expense236,739 225,959 219,035 215,110 160,779Fixed charges838,966 748,001 750,968 791,386 752,241Dividends on preferred stock and losses on purchases ofpreferred stock58,294 32,991 43,988 43,988 11,363Combined fixed charges and preferred stock dividends andlosses on purchases of preferred stock$897,260 $780,992 $794,956 $835,374 $763,604Ratio of earnings to fixed charges1.5 1.5 1.6 1.4 1.3(Deficiency) excess of earnings to cover fixed charges$459,048 $366,844 $469,024 $332,085 $249,169Ratio of earnings to combined fixed charges and preferred stockdividends and losses on purchases of preferred stock1.4 1.4 1.5 1.3 1.3(Deficiency) excess of earnings to cover combined fixedcharges and preferred stock dividends and losses onpurchases of preferred stock$400,754 $333,853 $425,036 $288,097 $237,806 EXHIBIT 21CROWN CASTLE INTERNATIONAL CORP. SUBSIDIARIESSubsidiary Jurisdiction ofIncorporationCC FN Holdings LLC DelawareCC Holdings GS V LLC DelawareCC Sunesys Fiber Networks LLC DelawareCC Towers Guarantor LLC DelawareCC Towers Holding LLC DelawareCCATT LLC DelawareCCATT Holdings LLC DelawareCCGS Holdings Corp. DelawareCCT2 Holdings LLC DelawareCCTM1 LLC DelawareCCTM Holdings LLC DelawareCCTMO LLC DelawareCrown Atlantic Company LLC DelawareCrown Castle Atlantic LLC DelawareCrown Castle CA Corp. DelawareCrown Castle BP ATT LLC DelawareCrown Castle GT Company LLC DelawareCrown Castle GT Corp. DelawareCrown Castle GT Holding Sub LLC DelawareCrown Castle International Corp. de Puerto Rico Puerto RicoCrown Castle Investment Corp. DelawareCrown Castle Investment II Corp. DelawareCrown Castle NG Central LLC DelawareCrown Castle NG East LLC DelawareCrown Castle NG Networks LLC DelawareCrown Castle NG West LLC DelawareCrown Castle Operating Company DelawareCrown Castle PT Inc. DelawareCrown Castle PR LLC Puerto RicoCrown Castle Solutions LLC DelawareCrown Castle South LLC DelawareCrown Castle Towers 06-2 LLC DelawareCrown Castle Towers LLC DelawareCrown Castle USA Inc. PennsylvaniaCrown Communication LLC DelawareFibernet Direct Holdings LLC DelawareFibernet Direct Texas LLC DelawareFibernet Direct TEL LLC DelawareFibernet Direct Florida LLC DelawareFibertech Holdings Corp. DelawareFibertech Networks, LLC DelawareFiber Technologies Networks, L.L.C. New YorkGlobal Signal Acquisitions LLC DelawareGlobal Signal Acquisitions II LLC DelawareGlobal Signal Acquisitions III LLC DelawareGlobal Signal Acquisitions IV LLC DelawareGlobal Signal GP LLC DelawareGlobal Signal Holdings III LLC DelawareGlobal Signal Operating Partnership, L.P. DelawareGoldenState Towers, LLC DelawareInfraSource FI, LLC DelawareLight Tower Clearinghouse LLC DelawareLightower Fiber Networks I, LLC DelawareLightower Fiber Networks II, LLC New YorkLight Tower Holdings LLC DelawareLTS Buyer LLC DelawareLTS Group Holdings LLC DelawareLTS Intermediate Holdings A LLC DelawareLTS Intermediate Holdings B LLC DelawareLTS Intermediate Holdings C LLC DelawareMW Cell REIT 1 LLC DelawareOP LLC DelawarePinnacle Towers Acquisition LLC DelawarePinnacle Towers Acquisition Holdings LLC DelawarePinnacle Towers LLC DelawarePR Site Development Corporation DelawareWCP Wireless Site RE Funding LLC DelawareWCP Wireless Site RE Holdco LLC DelawareSunesys, LLC DelawareTowers Development Corporation MarylandTowers Ventures III, LLC TennesseeSidera Networks, Inc. DelawareWilcon Holdings LLC DelawareYankee Metro Parent, Inc. DelawareExhibit 23.1Consent of Independent Registered Public Accounting FirmWe hereby consent to the incorporation by reference in the Registration Statements on Form S-3 ASR (No. 333-203074) and Form S-8 (No. 333-212383, 333-118659, 333-163843, 333-181715 and 333-188801) of Crown Castle International Corp. of our report dated February 26, 2018 relating to the financialstatements, financial statement schedules and the effectiveness of internal control over financial reporting, which appears in this Form 10-K. /s/ PricewaterhouseCoopers LLPPittsburgh, PennsylvaniaFebruary 26, 2018Exhibit 31.1CertificationFor the Year Ended December 31, 2017I, Jay A. Brown, certify that:1.I have reviewed this annual report on Form 10-K of Crown Castle International Corp. (“registrant”);2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make thestatements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by thisreport;3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects thefinancial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;4.The registrant's other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined inExchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:a)Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision,to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others withinthose entities, particularly during the period in which this report is being prepared;b)Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under oursupervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements forexternal purposes in accordance with generally accepted accounting principles;c)Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about theeffectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; andd)Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's mostrecent fiscal quarter (the registrant's fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likelyto materially affect, the registrant's internal control over financial reporting; and5.The registrant's other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to theregistrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):a)All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which arereasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; andb)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internalcontrol over financial reporting.Date: February 26, 2018 /s/ Jay A. BrownJay A. BrownPresident and Chief Executive OfficerExhibit 31.2CertificationFor the Year Ended December 31, 2017I, Daniel K. Schlanger, certify that:1.I have reviewed this annual report on Form 10-K of Crown Castle International Corp. (“registrant”);2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make thestatements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by thisreport;3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects thefinancial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;4.The registrant's other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined inExchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:a)Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision,to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others withinthose entities, particularly during the period in which this report is being prepared;b)Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under oursupervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements forexternal purposes in accordance with generally accepted accounting principles;c)Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about theeffectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; andd)Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's mostrecent fiscal quarter (the registrant's fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likelyto materially affect, the registrant's internal control over financial reporting; and5.The registrant's other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to theregistrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):a)All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which arereasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; andb)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internalcontrol over financial reporting.Date: February 26, 2018 /s/ Daniel K. SchlangerDaniel K. SchlangerSenior Vice President, Chief Financial Officer and TreasurerExhibit 32.1Certification Pursuant to18 U.S.C. Section 1350As Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002In connection with the Annual Report on Form 10-K of Crown Castle International Corp., a Delaware Corporation (“Company”), for the period endingDecember 31, 2017 as filed with the Securities and Exchange Commission on the date hereof (“Report”), each of the undersigned officers of the Companyhereby certifies pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to the best of such officer'sknowledge:1)the Report complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and2)the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of theCompany as of December 31, 2017 (the last date of the period covered by the Report). /s/ Jay A. BrownJay A. BrownPresident and Chief Executive OfficerFebruary 26, 2018 /s/ Daniel K. SchlangerDaniel K. SchlangerSenior Vice President, Chief Financial Officer and TreasurerFebruary 26, 2018A signed original of this written statement required by Section 906 of the Sarbanes-Oxley Act of 2002 has been provided to Crown Castle InternationalCorp. and will be retained by Crown Castle International Corp. and furnished to the Securities and Exchange Commission or its staff upon request.

Continue reading text version or see original annual report in PDF format above