In addition to the Big 43 wireless carriers (AT(T-Mobile, AT&T, T-Mobile, Sprint, and Verizon Wireless), we have also provided services or leased space to a number of customers including:

Sales and Marketing

Our sales and marketing goals are to:

use existing relationships and develop new relationships with wireless service providers to lease antenna space on and sell related services with respect to our owned towers or managed properties, enabling us to grow our site leasing business; and

successfully bid and win those site development services contracts that will contribute to our operating margins and/or provide a financial or strategic benefit to our site leasing business.

We approach sales on a company-wide basis, involving many of our employees. We have a dedicated sales force that is supplemented by members of our executive management team. Our dedicated salespeople are based regionally as well as in our

corporate office. We also rely on our vice presidents, general managers,directors, and other operations personnel to sell our services and cultivate customers.customer relationships. Our strategy is to delegate sales efforts by geographic region or to those employees of ours who have the best relationships with our customers. Most wireless service providers have national corporate headquarters with regional and local offices. We believe that wireless service providers make most decisions for site development and site leasing services at the regional and local levels with input from their corporate headquarters. Our sales representatives work with wireless service provider representatives at the regional and local levels and at the national level when appropriate. Our sales staff’s compensation is heavily weighted to incentive-based goals and measurements.

Competition

Domestic Site Leasing – In the U.S., our primary competitors for our site leasing activities are (1) large independent tower companies including American Tower Corporation and Crown Castle International, (2) a large number of regional independent tower owners, (3) wireless service providers that own and operate their own towers and lease, or may in the future decide to lease, antenna space to other providers, and (4) owners and operators of alternative facilities such as rooftops, outdoor and indoor distributed antenna system (“DAS”) networks, billboards, utility poles, and electric transmission towers.

International Site Leasing – Internationally, our competition consists of wireless service providers that own and operate their own tower networks, large multinational, national and regional independent tower companies, and alternative facilities such as rooftop, outdoor and indoor DAS networks, billboards, utility poles, and electric transmission towers. We believe that tower location and capacity, quality of service, density within a geographic market and, to a lesser extent, price historically have been and will continue to be the most significant competitive factors affecting the domestic and international site leasing business.

International Site Leasing –  Internationally, our competition consists of wireless service providers that own and operate their own tower networks, large national and regional independent tower companies, and alternative facilities such as rooftop, outdoor and indoor DAS networks, billboards, utility poles, and electric transmission towers.

Site Development – The site development business is competitive and price sensitive. We believe that the majority of our competitors in the U.S. site development business operate within local region and market areas, while some firms offer their services nationally. The market includes participants from a variety of market segments offering individual, or combinations of, competing services. The field of competitors includes site development consultants,companies, zoning consultants, real estate firms, wireless construction companies, tower owners/managers,owners, telecommunications equipment vendors, which provide end-to-end site development services through multiple subcontractors, and wireless service providers’ internal staff. We believe that providers base their decisions for site development services on a number of criteria, including company experience, price, track record, local reputation, geographic reach, and time for completion of a project.

EmployeesHuman Capital

Our corporate offices are located in our headquarters in Boca Raton, Florida. We also have employees located in our international, regional, and local offices. We consider our employee relations to be good. As of December 31, 2017,2020, we had 1,2911,483 employees of which 303421 were based outside of the U.S. and its territories. Of this total, our employees work in the following departments: 364 in site leasing operations, 387 in site development, 652 in corporate support, 57 in sales and marketing, and 23 in safety.

We considerseek to foster an inclusive work environment, and we respect the diversity our employees bring to the organization through their unique ideas, opinions and contributions. We believe it is essential to recognize and value these differences, which is one

of the many reasons SBA holds quarterly Town Hall meetings and other informal meetings with executives, elicits employee relationsfeedback, and conducts annual performance evaluations. In line with our commitment to be good.diversity, 23.1% of our U.S. new hires in 2020 were women and 34.4% were ethnic minorities.

The well-being of our employees is a crucial element of our culture, employee engagement, and productivity. We offer a competitive total rewards package which includes market-based pay, performance-based annual incentive awards, healthcare and retirement benefits, family leave, holiday and paid time off, and tuition assistance. We also invest in our employees’ professional growth and development by providing resources and opportunities to develop their skills and expand their expertise.

We value all those who serve our country and are proud to support military veterans and their families as they transition out of the military. SBA has earned the distinction of being a Military Friendly Employer and a Veteran Employer. We are proud to have veterans on our team - their integrity, work ethic, ability to adapt and strong teamwork skills blend well with the SBA core values. In 2020, over 7% of our employees were veterans, and we have collaborated with Hiring Our Heroes, DirectEmployers, and RecruitMilitary to actively hire veterans.

At SBA, providing a safe and healthy work environment for the protection of our employees is paramount. The safety of our tower climbers has been a key focus of the company since it started in 1989. In 2013, we opened our internal facility "Tower U" which provides a rigorous multi-day safety certification program that is required for all our employed tower climbers. We are proud of the fact that our average lost-day incident rate in the U.S. (days away from work due to workplace incidents) for 2020 was below the 2019 Bureau of Labor benchmark. Our "Tower U" safety professionals offer tower rescue training to first responders because we recognize that the safety of these first responders is paramount to the communities in which we operate.

Regulatory and Environmental Matters

Federal Regulations. In the U.S., which accounted for 80.6%79.7% of our total site leasing revenue for the year ended December 31, 2017,2020, both the Federal Communications Commission (the “FCC”) and the Federal Aviation Administration (the “FAA”) regulate towers. Many FAA requirements are implemented in FCC regulations. These regulations govern the construction, lighting, and painting or other marking of towers, as well as the maintenance, inspection, and record keeping related to towers, and may, depending on the characteristics of particular towers, require prior approval and registration of towers before they may be constructed, altered or used. Wireless communications equipment and radio or television stations operating on towers are separately regulated and may require independent customer licensing depending upon the particular frequency or frequency band used. In addition, any applicant for an FCC tower structure registration (through the FCC’s Antenna Structure Registration System) must certify that, consistent with the Anti-Drug Abuse Act of 1988, neither the applicant nor its principals are subject to a denial of federal benefits because of a conviction for the possession or distribution of a controlled substance. New tower construction also requires approval from the state or local governing authority for the proposed site:site; compliance with the National Environmental Policy Act (“NEPA”); compliance with the National Historic Preservation Act (“NHPA”); compliance with the Endangered Species Act (“ESA”); and may require notification to the FAA.

Pursuant to the requirements of the Communications Act of 1934, as amended, the FCC, in conjunction with the FAA, has developed standards to consider proposals involving new or modified towers. These standards mandate that the FCC and the FAA consider the height of the proposed tower, the relationship of the tower to existing natural or man-made obstructions, and the proximity of the tower to runways and airports. Proposals to construct or to modify existing towers above certain heights must be reviewed by the FAA to ensure the structure will not present a hazard to air navigation. The FAA may condition its issuance of a no-

hazardno-hazard determination upon compliance with specified lighting and/or painting requirements. Towers that meet certain height and location criteria must also be registered with the FCC. A tower that requires FAA clearance will not be registered by the FCC until it is cleared by the FAA. Upon registration, the FCC may also require special lighting and/or painting. Owners of wireless communications towers may have an obligation to maintain painting and lighting or other marking in conformance with FAA and FCC regulations. Tower owners and licensees that operate on those towers also bear the responsibility of monitoring any lighting systems and notifying the FAA of any lighting outage or malfunction.

Owners and operators of towers may be subject to, and therefore must comply with, environmental laws, including NEPA, NHPA and ESA. Any licensed radio facility on a tower is subject to environmental review pursuant to the NEPA, among other statutes, which requires federal agencies to evaluate the environmental impact of their decisions under certain circumstances. The FCC has issued regulations implementing the NEPA. These regulations place responsibility on applicants to investigate potential environmental effects of their operations and to disclose any potential significant effects on the environment in an environmental assessment prior to constructing or modifying a tower and prior to commencing certain operations of wireless communications or radio or television stations from the tower. In the event the FCC determines the proposed structure or operation would have a significant environmental impact based on the standards the FCC has developed, the FCC would be required to prepare an

environmental impact statement, which will be subject to public comment. This process could significantly delay the registration of a particular tower.

We generally indemnify our customers against any failure to comply with applicable regulatory standards relating to the construction, modification, or placement of towers. Failure to comply with the applicable requirements may lead to civil penalties.

The Telecommunications Act of 1996 amended the Communications Act of 1934 by preserving state and local zoning authorities’ jurisdiction over the construction, modification, and placement of towers. The law, however, limits local zoning authority by prohibiting any action that would discriminate among different providers of personal wireless services or ban altogether the construction, modification or placement of radio communication towers. Finally, the Telecommunications Act of 1996 requires the federal government to help licensees for wireless communications services gain access to preferred sites for their facilities. This may require that federal agencies and departments work directly with licensees to make federal property available for tower facilities.

As an owner and operator of real property, we are subject to certain environmental laws that impose strict, joint and several liability for the cleanup of on-site or off-site contamination and related personal injury or property damage. We are also subject to certain environmental laws that govern tower placement and may require pre-construction environmental studies. Operators of towers must also take into consideration certain radio frequency (“RF”) emissions regulations that impose a variety of procedural and operating requirements. Certain proposals to operate wireless communications and radio or television stations from tower structures are also reviewed by the FCC to ensure compliance with requirements relating to human exposure to RF emissions. Exposure to high levels of RF energy can produce negative health effects. The potential connection between low-level RF energy and certain negative health effects, including some forms of cancer, has been the subject of substantial study by the scientific community in recent years. We believe that we are in substantial compliance with and we have no material liability under any applicable environmental laws. These costs of compliance with existing or future environmental laws and liability related thereto may have a material adverse effect on our prospects, financial condition or results of operations.

State and Local Regulations. Most states regulate certain aspects of real estate acquisition, leasing activities, and construction activities. Where required, we conduct the site acquisition portions of our site development services business through licensed real estate brokers’ agents, who may be our employees or hired as independent contractors, and conduct the construction portions of our site development services through licensed contractors, who may be our employees or independent contractors. Local regulations include city and other local ordinances, zoning restrictions and restrictive covenants imposed by community developers. These regulations vary greatly from jurisdiction to jurisdiction, but typically require tower owners to obtain approval from local officials or community standards organizations, or certain other entities prior to tower construction and establish regulations regarding maintenance and removal of towers. FCC rules establish presumptively reasonable time periods for state and local authorities to act on applications to collocate a facility or deploy a facility, such as a tower. In addition, many local zoning authorities require tower owners to post bonds or cash collateral to secure their removal obligations. Local zoning authorities generally have been unreceptive to construction of new towers in their communities because of the height and visibility of the towers, and have, in some instances, instituted moratoria. However, in August 2018, the FCC issued a declaratory ruling stating that express and de facto moratoria on deployment of telecommunications facilities violate the Communications Act. This FCC ruling has been affirmed by a federal appellate court.

International Regulations. Regulatory regimes outside of the U.S. and its territories vary by country and locality; however, these regulations typically require tower owners and/or licensees to obtain approval from local officials or government agencies prior to tower construction or modification or the addition of a new antenna to an existing tower. Additionally, some regulations include ongoing obligations regarding painting, lighting, and maintenance. Our international operations may also be subject to limitations on foreign ownership of land in certain areas. Based on our experience to date, these regimes have been similar to, but not more rigorous, burdensome or comprehensive than, those in the U.S. Non-compliance with such regulations may lead to monetary penalties or deconstruction orders. Our international operations are also subject to various regulations and guidelines regarding employee relations

and other occupational health and safety matters. As we expand our operations into additional international geographic areas, we will be subject to regulations in these jurisdictions.

Backlog

Backlog related to our site leasing business consists of lease agreements and amendments, which have been signed, but have not yet commenced. As of December 31, 2017, we had 1,205 new leases and amendments which had been executed with customers but which had not begun generating revenue. These leases and amendments will contractually provide for approximately $9.2 million of annual revenue. By comparison, as of December 31, 2016, we had 955 new leases and amendments which had been executed with customers but which had not begun generating revenue. These leases and amendments contractually provided for approximately $8.7 million of annual revenue.

Our backlog for site development services consists of the value of work that has not yet been completed under executed contracts. As of December 31, 2017, we had approximately $47.5 million of contractually committed revenue as compared to approximately $26.0 million as of December 31, 2016.  

Availability of Reports and Other Information

SBA Communications Corporation was incorporated in the State of Florida in March 1997.1997 and is a real estate investment trust (“REIT”) for federal income tax purposes. Our corporate website is www.sbasite.com. We make available, free of charge, access to our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, Proxy Statement on Schedule 14A and amendments to those materials filed or furnished pursuant to Section 13(a) or 15(d) of the Securities and Exchange Act of 1934, as amended (the “Exchange Act”), on our website under “Investor Relations – Reports and Results – SEC Filings,” as soon as

reasonably practicable after we file electronically such material with, or furnish it to, the United States Securities and Exchange Commission (the “Commission”).

ITEM 1A. RISK FACTORS

Risks Related to Our Business

If our wireless service provider customers combine their operations to a significant degree, our future operating results, ability to service our indebtedness, and stock price could be adversely affected.

Our wireless service providers have and may continue to be subject to consolidation pressures. Significant consolidation among our wireless service provider customers mayhave resulted and are expected to continue to result in our customers failing to renew existing leases for tower space as a result of overlapping coverage or reducing future capital expenditures in the aggregate because their existing networks and expansion plans may overlap or be very similar, or acquired technologies may be discontinued. In connection with the combinationssimilar. T-Mobile, Sprint, AT&T, and Verizon have grown through acquisitions of Verizon Wireless and ALLTEL (to form Verizon Wireless), Cingular and AT&T Wireless (to form AT&T Mobility) and Sprint PCS and Nextel (to form Sprint),other wireless service providers. As a result, the combined companies have rationalized duplicative parts of their networks, and, in the case of Sprint, the Nextel iDEN network was discontinued, which has leddiscontinued. During 2020, the consolidation of T-Mobile and may continueSprint was completed, reducing the number of national wireless service providers in the U.S. to leadthree. During the second half of 2020 we began to theexperience non-renewal of certain leases as a result of the T-Mobile/Sprint merger and we expect to continue to experience churn arising from this merger in the upcoming years. For the year ended December 31, 2020, leases with T-Mobile and Sprint, as they existed prior to the merger, represented approximately 17.6% and 14.7% of our total site leasing revenue, respectively. The revenue generated from legacy Sprint leases where both legacy T-Mobile and legacy Sprint overlap on sites where both companies leased space represented 5.9% of our towers. During 2013,total site leasing revenue for the year ended December 31, 2020, excluding, and incremental to, the impact from previously disclosed expected consolidation churn from T-Mobile’s MetroPCS and Sprint’s Clearwire networks. In addition, these overlapping sites have an average remaining current term of approximately 3.7 years and 5.0 years with Sprint acquired Clearwire Communications and T-Mobile, respectively, as they existed pre-merger.

Consolidation of wireless service providers has also occurred in some of our international markets and could continue to occur. For example, in January 2019, Claro acquired MetroPCS,Telefonica’s assets in Guatemala and in 2014, AT&TJuly 2020 Liberty Latin American acquired Leap Wireless (Cricket Wireless). These consolidations have ledTelefonica’s assets in Costa Rica, three markets in which we own and operate towers. Furthermore, Telefonica has announced its intent to sell its operations in its other Latin American markets, other than Brazil. In Brazil, as a result of Oi S.A.’s recent restructuring, the Court has approved the sale of all of Oi’s wireless tower assets to the three other telecommunications providers in Brazil, Telefonica, Claro, and TIM. The sale is subject to regulatory and anti-trust authorizations and the designation of which assets will be assigned to which carrier has not yet been publicized; however, we expect that a portion of our 7,492 tower leases that we had with Oi as of December 31, 2020 will be subject to overlap and may continue to leadbe subject to non-renewal upon expiration of certainthe leases. As of December 31, 2020, our tower leases. leases with Oi have an average remaining current term of approximately 13.4 years.

If our wireless service provider customers continue to consolidate as a result of, among other factors, limited wireless spectrum, for commercial use in the U.S., these consolidations could significantly impact the number of tower leases that are not renewed or the number of new leases that our wireless service provider customers require to expand their networks, which could materially and adversely affect our future operating results and our ability to service our indebtedness. These risks could be exacerbated due to changes in governmental policy that may favor industry consolidation.

We depend on a relatively small number of customers for most of our revenue, and the loss, consolidation or financial instability of any of our significant customers may materially decrease our revenue and adversely affect our financial condition.

We derive a significant portion of our revenue from a small number of customers. Consequently, a reduction in demand for site leasing, reduced future capital expenditures on the networks, or the loss, as a result of bankruptcy, merger with other customers of ours or otherwise, of any of our largest customers could materially decrease our revenue and have an adverse effect on our growth.

We derive revenue through numerous site leasing contracts and site development contracts. In the United States and Canada, each site leasing contract relates to the lease of space at an individual tower and is generally for an initial term of five years to 10 years with multiple renewal periods at the option of the tenant. Tenant leases in South Africa and our Central and South American markets typically have an initial term of 10 years with multiple renewal periods. However, if any of our significant site leasing customers were to experience financial difficulty, substantially reduce their capital expenditures or reduce their dependence on leased tower space and fail to renew their leases with us, our revenues, future revenue growth and results of operations would be adversely affected. For example, in January 2018, Oi, S.A. (“Oi”), our largest customer in Brazil, emerged from bankruptcy with a reorganization plan and is expected to resolve all of its pre-petition obligations by 2022. During 2020, as part of its recent restructuring, the Court has approved the sale of all of Oi’s wireless tower assets to the three other telecommunications providers in Brazil, Telefonica, Claro, and TIM. The

sale is subject to regulatory and anti-trust authorizations and the designation of which assets will be assigned to which carrier has not yet been publicized. In addition, the market pricemany of our Class A common stocktenants in our international markets are subsidiaries of global telecommunications companies. These subsidiaries may not have the explicit or implied financial support of their parent entities, which may impact their creditworthiness.

Our site development customers engage us on a project-by-project basis, and a customer can generally terminate an assignment at any time without penalty. In addition, a customer’s need for site development services can decrease, and we may not be affected by the economic and market perceptionsuccessful in establishing relationships with new customers. Furthermore, our existing customers may not continue to engage us for additional projects.

The following is a list of significant customers (representing at least 10% of revenue in any of the announcement or consummationlast three years) and the percentage of wireless service provider customer consolidationsour total revenues for the specified time periods derived from these customers:

(1)Prior year amounts have been adjusted to reflect the merger of T-Mobile and their impact onSprint.

We also have client concentrations with respect to revenues in each of our future operating results.financial reporting segments:

(1)Prior year amounts have been adjusted to reflect the merger of T-Mobile and Sprint.

We have a substantial level of indebtedness which may have an adverse effect on our business or limit our ability to take advantage of business, strategic or financing opportunities.

As indicated below, we have and will continue to have a significant amount of indebtedness relative to our deficit.indebtedness. The following table sets forth our total principal amount of debt and shareholders’ deficit as of December 31, 20172020 and 2016.  

2019.

As a consequence of our indebtedness, (1) demands on our cash resources may increase, (2) we are subject to restrictive covenants that further limit our financial and operating flexibility and (3) we may choose to institute self-imposed limits on our indebtedness based on certain considerations including market interest rates, our relative leverage and our strategic plans. For example, as a result of our substantial level of indebtedness and the uncertainties arising in the credit markets and the U.S. economy:

•we may be more vulnerable to general adverse economic and industry conditions;

•we may have to pay higher interest rates upon refinancing or on our variable rate indebtedness if interest rates rise, thereby reducing our cash flows;

•we may find it more difficult to obtain additional financing to fund future working capital, capital expenditures and other general corporate requirements that would be in our best long-term interests;

•we may be required to dedicate a substantial portion of our cash flow from operations to the payment of principal and interest on our debt, reducing the available cash flow to fund other investments, including share repurchases, tower acquisition and new build capital expenditures, or to satisfy our REIT distribution requirements;

•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 that are less leveraged; and

•we may be required to sell debt or equity securities or sell some of our core assets, possibly on unfavorable terms, in order to meet payment obligations.

These restrictionsOur variable rate indebtedness and refinancing obligations subject us to interest rate risk, which could have a material adverse effect oncause our business by limiting our abilitydebt service obligations to take advantage of financing, new tower development, mergers and acquisitions, share repurchases, or other opportunities and to satisfy our REIT distribution requirements.  increase significantly.

In addition, fluctuationsFluctuations in market interest rates or changes in central bank monetary policy may increase interest expense relating to our floating rate indebtedness, which we expect to incur pursuant to our Revolving Credit Facility and Term Loans,Loan, and may make it difficult to refinance our existing indebtedness at a commercially reasonable rate or at all. There is no guarantee that the future refinancing of our indebtedness will have fixed interest rates or that interest rates on such indebtedness will be equal to or lower than the rates on our current indebtedness.

Our variable rate indebtedness and refinancing obligations subject us to interest rate risk, which could cause our debt service obligations to increase significantly.

An increase in market interest rates would increase our interest expense arising on our existing and future floating rate indebtedness or upon refinancing of our fixed rate debt. Pursuant to the terms of our Credit Agreement, the interest rate that we pay on indebtedness incurred under the Revolving Credit Facility or Term Loans varies based on a fixed margin over either a base rate or a Eurodollar rate which references the LIBOR rate. As of December 31, 2020, this indebtedness represented approximately $2.7 billion, or 24.3% of our total indebtedness. As a result, we are exposed to interest rate risk. Interest rates, including LIBOR, have recently increasedfluctuate periodically and are expected to continue toas such may increase in future periods. If interest rates continue to increase, our debt service obligations on the variable rate indebtedness will increase even though the amount borrowed remained the same, and our net income and cash flows, including cash available for servicing our indebtedness, will correspondingly decrease. Furthermore,In addition, LIBOR is the subject of recent proposals for reform, and the U.K. Financial Conduct Authority announced its desire to phase out the use of LIBOR by June of 2023. This may cause LIBOR to disappear entirely or perform differently than in an environment of increasingthe past. If LIBOR ceases to exist, the method and rate used to calculate our interest rates it is likely that anyand/or payments on our variable rate indebtedness under our Credit Agreement, which matures beyond 2021, in the future refinancing of our indebtedness will be either at fixedmay result in interest rates and/or payments that are higher than, our current fixedlower than or that do not otherwise correlate over time with the interest rates and/or at variable rates. Inpayments that would have been applicable to our obligations if LIBOR was available in its current form. As such, the future,potential effect of any such event is uncertain, but were it to occur, our cost of capital, financial results, cash flows and results of operations may be adversely affected. It is unknown whether any alternative reference rates will attain market acceptance as replacements of LIBOR.

Although we may enter intohave used interest rate swaps that involve the exchange of floating for fixed rate interest payments in order to reduce interest rate volatility. However,mitigate this risk from time to time, we may not maintain interest rate swaps with respect to all of our variable rate indebtedness, and any swaps we enter into may not fully mitigate our interest rate risk. We currently have noFurthermore, the increase in our use of derivative instruments increases our exposure to counterparty credit risk to the extent that a counterparty to the instrument fails to meet or perform the terms of the instrument. As of December 31, 2020, we had interest rate swaps.

We dependswaps on a relatively small number of customers for mostportion of our revenue,2018 Term Loan that fixed $1.95 billion in notional value for approximately 4.25 years receiving interest at one-month LIBOR plus 175 basis points and paying a fixed rate of 1.874%.

The discontinuation of LIBOR could adversely affect our operating results and financial condition.

LIBOR has been the loss, consolidation subject of recent proposals for reform, and, in July 2017, the U.K. Financial Conduct Authority announced its desire to phase out the use of LIBOR by the end of 2021. These reforms may cause LIBOR to perform differently than it has in the past, and LIBOR may ultimately cease to exist after June 2023. These reforms will cause LIBOR to cease to exist and will cause the establishment of an alternative reference rate(s). The U.S. Federal Reserve, in conjunction with the Alternative Reference Rates Committee, is proposing to replace U.S. dollar LIBOR with a newly created index which is calculated based on repurchase agreements backed by treasury securities. These alternative rates, if adopted, would be used to calculate our interest rates and/or

payments on our variable rate indebtedness under our Credit Agreement, which matures beyond 2021. Any new reference rate may result in interest rates and/or financial instabilitypayments that are higher than, lower than or that do not otherwise correlate over time with the interest rates and/or payments that would have been applicable to our obligations if LIBOR was available in its current form. As such, the potential effect of any such event is uncertain, but were it to occur, our cost of capital, financial results, cash flows and results of operations may be adversely affected. It is unknown whether any alternative reference rates will attain market acceptance as replacements of LIBOR.

If LIBOR ceases to exist after 2021, the interest rate on our significant customersinterest rate swaps may not exactly conform to the new interest rate under our Credit Agreement. If the fallback LIBOR rate to our interest rate swaps differs from the fallback LIBOR rate under our Credit Agreement, our interest rate swaps could be at least partially ineffective as a hedge and could require us to mark-to-market the ineffective portion of the interest rate swap through our income statement.

Increasing competition in the tower industry may create pricing pressures or result in non-renewals that may materially decreaseand adversely affect us.

Our industry is highly competitive, and our revenuewireless service provider customers sometimes have alternatives for leasing antenna space. We believe that tower location and capacity, quality of service, density within a geographic market and, to a lesser extent, price historically have been and will continue to be the most significant competitive factors affecting the site leasing business. However, competitive pricing pressures for tenants on towers from competitors could materially and adversely affect our lease rates or lead to non-renewals of existing leases. Furthermore, pricing pressures could lead to more prevalent network sharing, both domestically and internationally, which could reduce the demand for our tower space or lead to non-renewals of existing leases. In addition, the increasing number of towers (1) may provide customers the ability to relocate their antennas to other towers if they determine that a more suitable, efficient or economical location exists, which could lead to non-renewal of existing leases, or (2) may adversely impact our ability to enter into new customer leases. This impact may be exacerbated if competitors construct towers near our existing towers. Any of these factors could materially and adversely affect our growth rate and our future operations.

In the site leasing business, we compete with:

•wireless service providers that own and operate their own towers and lease, or may in the future decide to lease, antenna space to other providers;

•national and regional tower companies who may be substantially larger and have greater financial condition.resources than we do;

We derive•international tower companies who have been in the international market for a significant portionlonger period of time than we have; and

•alternative facilities such as rooftops, outdoor and indoor DAS networks, billboards and electric transmission towers.

The site development segment of our revenue from aindustry is also competitive. There are numerous large and small numbercompanies that offer one or more of customers. Consequently, a reduction in demand forthe services offered by our site leasing, reduced future capital expenditures on the networks, or the loss, asdevelopment business. As a result of bankruptcy, merger with other customers of ours or otherwise, of anythis competition, margins in this segment may come under pressure. Many of our largest customers could materiallycompetitors have lower overhead expenses and therefore may be able to provide services at prices that we consider unprofitable. If margins in this segment were to decrease, our revenueconsolidated revenues and have an adverse effect on our growth.

On June 20, 2016, Oi, S.A. (“Oi”), our largest customer in Brazil, filed a petition for judicial reorganization in Brazil. For the year ended December 31, 2017, Oi comprised approximately 7.5% of our total site leasing revenue. While we initially recorded a $16.5 million bad debt provision during the second quarter of 2016 relating to amounts owed or potentially owed by Oi as of the petition date, since that date we have continued to do business with Oi in the ordinary course. On January 8, 2018, Oi’s reorganization plan was approved by the Brazilian courts and Oi is expected to resolve all its pre-petition obligations in accordance with the terms of the plan. However, if Oi is unable to successfully fulfill its reorganization obligations or cannot operate its business on a go-forward basis, it could adversely affect our future results of operation.

The following is a list of significant customers (representing at least 10% of revenue in any of the last three years) and the percentage of our total revenues for the specified time periods derived from these customers:

We also have client concentrations with respect to revenues in each of our financial reporting segments:

We derive revenue through numerous site leasing contracts and site development contracts. Each site leasing contract relates to the lease of space at an individual tower and is generally for an initial term of five to ten years in the U.S. and Canada, and renewable for five 5-year periods at the option of the tenant. Site leasing contracts in our Central American and South American markets typically have an initial term of ten years with multiple five year renewal periods. However, if any of our significant site leasing customers were to experience financial difficulty, substantially reduce their capital expenditures or reduce their dependence on leased tower space and fail to renew their leases with us, our revenues, future revenue growth and results of operations wouldsegment operating profit could be adversely affected. In addition, many of our tenants in our international markets are subsidiaries of global telecommunications companies. These subsidiaries may not have the explicit or implied financial support of their parent entities, which may impact their creditworthiness.

Our site development customers engage us on a project-by-project basis, and a customer can generally terminate an assignment at any time without penalty. In addition, a customer’s need for site development services can decrease, and we may not be successful in establishing relationships with new customers. Furthermore, our existing customers may not continue to engage us for additional projects.

Increasing competition may negatively impact our ability to grow our communication site portfolio long term.

We intend to continue growing our tower portfolio, domestically and internationally, through acquisitions and new builds. Our ability to meet our growth targets significantly depends on our ability to build or acquire existing towers that meet our investment requirements. Traditionally, our acquisition strategy has focused on acquiring towers from smaller tower companies, independent tower developers and wireless service providers. However, as a result of consolidation in the tower industry, there are fewer of these mid-sized tower transactions available in the U.S. and there is more competition to acquire existing towers. Increased competition for acquisitions may result in fewer acquisition opportunities for us, higher acquisition prices, and increased difficulty in negotiating and consummating agreements to acquire such towers. For example, in 2017,2020, we passed on more U.S. acquisitions than we did in 20162019 due to asset quality, price, or lease terms. Furthermore, to the extent that the tower acquisition opportunities are for significant tower portfolios, manysome of our competitors are significantly larger and have greater financial resources than we do. Finally, laws regulating competition, domestically and internationally, may limit our ability to acquire certain portfolios. As a result of these risks, the cost of acquiring these towers may be higher than we expect or we may not be able to meet our annual and long-term tower portfolio growth targets. If we are not able to successfully address these challenges, we may not be able to materially increase our tower portfolio in the long-term through acquisitions.

Our ability to build new towers is dependent upon the availability of sufficient capital to fund construction, our ability to locate, and acquire at commercially reasonable prices, attractive locations for such towers and our ability to obtain the necessary zoning and permits. Local regulations, including municipal or local ordinances, zoning restrictions and restrictive covenants imposed

by community developers, vary greatly, but typically require antenna tower and structure owners to obtain approval from local officials or community standards organizations prior to tower or structure construction or modification. With respect to our international new builds, our tower construction may be delayed or halted as a result of local zoning restrictions, inconsistencies between laws or other barriers to construction in international markets. Due to these risks, it may take longer to complete our new tower builds than anticipated, domestically and internationally, than anticipated, and the costs of constructing these towers may be higher than we expect or we may not be able to add as many towers as we had planned in 2018.2021. If we are not able to increase our new build tower portfolio as anticipated, it could negatively impact our ability to achieve our financial goals.

Increasing competition in the tower industry may create pricing pressures or result in non-renewals that may materially and adversely affect us.

Our industry is highly competitive, and our wireless service provider customers sometimes have alternatives for leasing antenna space. However, we believe that tower location and capacity, quality of service, density within a geographic market and, to a lesser extent, price historically have been and will continue to be the most significant competitive factors affecting the site leasing business. However competitive pricing pressures for tenants on towers from competitors could materially and adversely affect our lease rates.  In addition, the increasing number of towers (1) may provide customers the ability to relocate their antennae to other towers if they determine that a more suitable, efficient or economic location exists, which could lead to non-renewal of existing leases, or (2) may adversely impact our ability to enter into new customer leases. Any of these factors could materially and adversely affect our growth rate and our future operations.

In the site leasing business, we compete with:

•wireless service providers that own and operate their own towers and lease, or may in the future decide to lease, antenna space to other providers;

•national and regional tower companies who may be substantially larger and have greater financial resources than we do; and

•alternative facilities such as rooftops, outdoor and indoor DAS networks, billboards and electric transmission towers.

The site development segment of our industry is also competitive. There are numerous large and small companies that offer one or more of the services offered by our site development business. As a result of this competition, margins in this segment may come under pressure. Many of our competitors have lower overhead expenses and therefore may be able to provide services at prices that we consider unprofitable. If margins in this segment were to decrease, our consolidated revenues and our site development segment operating profit could be adversely affected.

A slowdown in demand for wireless communications services or for tower space could materially and adversely affect our future growth and revenues, and we cannot control that demand.

Additional revenue growth on our towers other than through contractual escalators comes directly from additional investment by our wireless service provider customers in their networks. If consumers significantly reduce their minutes of use or data usage, or fail to widely adopt and use wireless data applications, our wireless service provider customers could experience a decrease in demand for their services. Regardless of consumer demand, each wireless service provider must have substantial capital resources and capabilities to build out their wireless networks, including licenses for spectrum. In addition, our wireless service customers have engaged in increased use of network sharing, roaming or resale arrangements. As a result of all of the above, wireless service providers may scale back their business plans or otherwise reduce their spending, which could materially and adversely affect demand for our tower space and our wireless communications services business, which could have a material adverse effect on our business, results of operations and financial condition.

Our international operations are subject to economic, political and other risks that could materially and adversely affect our revenues or financial position.

Our current business operations in Canada, Central America, and South America,developing markets, and our expansion into any other international markets in the future, could result in adverse financial consequences and operational problems not typically experienced in the United States. The consolidated revenues generated by our international operations were approximately 18.2%19.0% during the year ended December 31, 2017,2020, and we anticipate that our revenues from our international operations will continue to grow in the future. Accordingly, our business is and will in the future be subject to risks associated with doing business internationally, including:

•changes in a specific country’s or region’s political or economic conditions;

•laws and regulations that tax or otherwise restrict repatriation of earnings or other funds or otherwise limit distributions of capital;

•laws and regulations that dictate how we operate our towers and conduct business, including zoning, maintenance and environmental matters, and laws related to ownership of real property;

•changes in a specific country’s or region’s political or economic conditions, including inflation or currency devaluation;

•laws affecting telecommunications infrastructure including the sharing of such infrastructure;

•laws and regulations governing our employee relations, including occupational health and safety matters;that tax or otherwise restrict repatriation of earnings or other funds or otherwise limit distributions of capital;

•changes to existing or new domestic or international tax laws, new or significantly increased municipal fees directed specifically at the ownership and operation of towers, which may be applied and enforced retroactively;retroactively and could materially affect the profitability of our operations;

•expropriation and governmental regulation restricting foreign ownership or requiring reversion or divestiture;

•laws effecting telecommunications infrastructuregovernmental regulations and restrictions impacting tower licenses, spectrum licenses and concessions, including additional restrictions on the sharing of such infrastructure;

•restrictionuse or revocation of such licenses, concessions or spectrum and additional conditions to receive or maintain such licenses;

•laws and regulations governing our employee relations, including occupational health and safety matters and employee compensation and benefits matters;

•our ability to comply with, and the costs of compliance with, anti-bribery laws such as the Foreign Corrupt Practices Act and similar local anti-bribery laws;

•our ability to compete with owners and operators of wireless towers that have been in the international market for a longer period of time than we have;

•uncertainties regarding legal or judicial systems, including inconsistencies between and within laws, regulations and decrees, and judicial application thereof, and delays in the judicial process;

•health or similar issues, such as a pandemic or epidemic;challenges arising from less-developed infrastructure in certain markets; and

•difficulty in recruiting and retaining trained personnel;personnel.

We are also exposed to risks operating in countries with high levels of inflation, including the risk that inflation rates exceed our fixed escalator percentages in markets where our leases include fixed escalators and the risk that adverse economic conditions may discourage growth in consumer demand and consequently reduce our customers’ demand for our site leasing services. For example, we have a subsidiary in Argentina through which we operate our site leasing business. The Argentinean economy was deemed to be “highly inflationary” from a U.S. GAAP perspective as of the second quarter of 2018 and remains highly inflationary as of December 31, 2020. As a result, we remeasured the financial statements for those operations to the U.S. dollar as of July 1, 2018. Although this change did not have a material impact on our financial statements as our assets in and revenue from Argentina were each less than 1% of consolidated assets and revenue, respectively, as of December 31, 2020, going forward, fluctuations in the Argentinean Peso to U.S. dollar exchange rate could negatively impact our financial results.

•languageCurrency fluctuations may negatively affect our results of operations.

Our operations in Central America and cultural differences.Ecuador are primarily denominated in U.S. Dollars. In Brazil, Canada, Chile, and South Africa, significantly all of our revenue, expenses, and capital expenditures, including tenant leases, ground leases and other property interests, and other tower-related expenses are denominated in local currency. In Colombia, Argentina, and Peru, our revenue, expenses, and capital expenditures, including tenant leases, ground leases and other property interests, and other tower-related expenses are denominated in a mix of local currency and U.S. dollars. Our foreign currency denominated revenues and expenses are translated into U.S. dollars at average exchange rates for inclusion in our consolidated financial statements.

For the year ended December 31, 2020, approximately 20.4% of our total cash site leasing revenue was generated by our international operations, of which 14.5% was generated in non-U.S. dollar currencies, including 11.4% which was denominated in Brazilian Reais. The exchange rates between our foreign currencies and the U.S. Dollar have fluctuated significantly in recent years and may continue to do so in the future. For example, the Brazilian Real has historically been subject to substantial volatility and weakened 22.8% when comparing the average rate for the years ended December 31, 2020 and 2019. This trend has affected, and may in the future continue to affect, our reported results of operations.

Changes in exchange rates between these local currencies and the U.S. dollar will affect the recorded levels of site leasing revenue, segment operating profit, assets and/or liabilities. Volatility in foreign currency exchange rates can also affect our ability to plan, forecast and budget for our international operations and expansion efforts.

Furthermore, we have intercompany loan agreements with our foreign subsidiaries to borrow in U.S. Dollars. As of December 31, 2020 and 2019, the aggregate amount outstanding under the intercompany loan agreements subject to remeasurement with our foreign subsidiaries was $909.8 million and $899.7 million, respectively. In accordance with ASC 830, we remeasure foreign denominated intercompany loans with the corresponding change in the balance being recorded in Other income (expense), net in our Consolidated Statements of Operations as settlement is anticipated or planned in the foreseeable future. Consequently, if the U.S. Dollar strengthens against the Brazilian Real or the South African Rand, our results of operations would be adversely affected. For the years ended December 31, 2020 and 2019, we recorded a $145.6 million loss and a $9.0 million gain, net of taxes, respectively, on the remeasurement of intercompany loans due to changes in foreign exchange rates. For the year ended December 31, 2020, we repaid $25.8 million under our intercompany loan with our Brazilian subsidiary.

Delays in the roll-out of new spectrum, due to a slowdown in demand for wireless services, the inability or unwillingness of wireless service providers to invest in their infrastructure or delays in the availability of new spectrum could materially and adversely affect our future growth and revenues.

We expect a significant portion of our future revenue growth will result from investments in the deployment of new or fallow spectrum by our wireless service provider customers. Wireless service providers typically invest in their networks in response to consumer demand for additional or higher quality service. If consumers significantly reduce their use of wireless services or fail to widely adopt and use new wireless technologies and their products and applications, our wireless service provider customers could experience a reduction in the rate of growth of or a decrease in demand for their services and therefore reduce the amount they invest in their network.

Regardless of consumer demand, each wireless service provider must have substantial capital resources and capabilities to deploy new spectrum in their wireless networks, including licenses for spectrum. If some or all of our wireless service providers are unwilling or unable to significantly invest in their networks, it could adversely affect our revenue growth. However, if any of these wireless service provider customers or other wireless service providers are unable to access sufficient capital to develop their spectrum, then overall demand for our towers and services could be adversely affected.

The FCC continues to auction new bands of spectrum, including CBRS and C-Band. Our customers have been and are expected to be the primary winners of these auctions and subsequently deploy this spectrum on our portfolio which would provide us with a revenue growth opportunity. Any delays or failure of these auctions could negatively impact future demand for our towers. Similarly, any delays in the clearing or availability of this spectrum subsequent to these auctions could delay the related demand for our towers.

New technologies or network architecture or changes in a customer’s business model may reduce demand for our wireless infrastructure or negatively impact our revenues.

Improvements or changes in the efficiency, architecture, and design of wireless networks or changes in a wireless service provider customer's business model may reduce the demand for our wireless infrastructure. Also, as customers deploy increased capital to develop and implement new technologies, they may allocate less of their budgets to lease space on our towers. For example, new technologies that may promote network sharing, joint development, or resale agreements by our wireless service provider customers, such as signal combining technologies or network functions virtualization, may reduce the need for our wireless infrastructure, or may result in the decommissioning of equipment on certain sites because portions of the customers' networks may become redundant. In addition, other technologies and architectures, such as WiFi, 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, the traditional macro site communications architecture that is the basis of substantially all of our site leasing business. The majority of our tower portfolio comprises traditional macro sites and therefore is not as diversified into non-macro sites and other technologies and architectures as some of our competitors. In addition, new technologies that enhance the range, efficiency, and capacity of wireless

equipment could reduce demand for our wireless infrastructure. For example, our wireless service provider customers have engaged in increased use of network sharing, roaming, or resale arrangements, resulting in reduced capital spending or a decision to sell or not renew their spectrum licenses or concessions. Any significant reduction in demand for our wireless infrastructure resulting from new technologies or new architectures or changes in a customer's business model may negatively impact our revenues or otherwise have a material adverse effect.  Any such event may have a disproportionate impact on our business compared to our competitors, whose portfolios may be more technologically and architecturally diversified than ours. In addition, while we are exploring and investing in ancillary services and emerging technologies, including our mobile edge computing initiative and private networks, those investments may not prove to be profitable, which could divert management's attention from other value-enhancing opportunities.

These factors could also have a material adverse effect on our growth rate since growth opportunities and demand for our tower space as a result of new technologies may not be realized at the times or to the extent anticipated. Any of these factors could have a material adverse effect on our business, results of operations and financial condition.

If we are unable to protect our rights to the land under our towers, it could adversely affect our business and operating results.

Our real property interests relating to the land under our tower structures consist primarily of leasehold and sub-leasehold interests, fee interests, easements, licenses, rights-of-way, and other similar interests. From time to time, we experience disputes with landowners regarding the terms of the agreements for the land under our tower structures, which can affect our ability to access and operate such towers. Further, landowners may not want to renew their agreements with us, they may lose their rights to the land, or they may transfer their landproperty interests to third parties, including ground leaseproperty interest aggregators and our competitors, which could affect our ability to renew agreements on commercially viable terms or at all. In addition, the land underlying the 2,113 towers we acquired in 2013 fromWe currently have 35-year non-terminable leases with Oi, one of Brazil’s largest telecommunications providers, with respect to 2,113 towers that we acquired in 2013. The land underneath these towers is currently subject to a concession from the Federal Republic of Brazil that expires in 2025. At the end of the term, the Brazilian government will have the right to (i)(1) renew the concession upon newly negotiated terms or (ii)(2) terminate the concession and take possession of the land and the tower on such land. Although Oi hasAt the time we acquired the towers, we also entered into a non-terminable lease with us for 35 years,right of first refusal to purchase such land to the extent that the Brazilian regulations permit those assets to be sold. Brazil has recently adopted a new telecommunications law that is expected to provide Oi and/or the Brazilian government rights to sell the land underlying these assets; however, as the regulations implementing this new law have not yet been promulgated, the amount, if at all, that we would be required to pay to purchase such interests is undetermined. If the concession is not renewed and we are unable to purchase the land, then our site leasing revenue from co-located tenants would terminate prior to the end of such lease. For the year ended December 31, 2017,2020, we generated 11.5%6.9% of our total international site leasing revenue from these 2,113 towers of which 7.3% related to Oi and 4.2% represented revenue from co-located tenants.towers.

As of December 31, 2017,2020, the average remaining life under our ground leases and other property interests, including renewal options under our control, was approximately 3335 years, and approximately 6.9%10.6% of our tower structures have ground leases or other property interests maturing in the next 10 years. Failure to protect our rights to the land under our towers may have a material adverse effect on our business, results of operations or financial condition.

New technologies or network architecture or changes in a customer’s business model may reduce demand for our wireless infrastructure or negatively impact our revenues.

Improvements or changes in the efficiency, architecture, and design of wireless networks or changes in a wireless service provider customer’s business model may reduce the demand for our wireless infrastructure. In addition, as customers deploy increased capital to the development and implementation of new technologies, they may allocate less of their budgets to lease space on our towers. For example, new technologies that may promote network sharing, joint development, or resale agreements by our wireless service provider customers, such as signal combining technologies or network functions virtualization, may reduce the need for our wireless infrastructure. In addition, other technologies and architectures, such as WiFi, 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, the traditional macro site cellular architecture that is the basis of substantially all of our site leasing business. In addition, new technologies that enhance the range, efficiency, and capacity of wireless equipment could reduce demand for our wireless infrastructure. Further, a customer may decide to no longer outsource wireless infrastructure or otherwise change its business model. Any significant reduction in demand for our wireless infrastructure resulting from new technologies or new architectures or changes in a customer’s business model may negatively impact our revenues or otherwise have a material adverse effect on us. 

Currency fluctuations may negatively affect our results of operations.

Our operations in Central America and Ecuador are primarily denominated in U.S. Dollars. In Brazil, Canada, Chile, and Colombia, significantly all of our revenue, expenses, and capital expenditures, including tenant leases, ground leases, and other tower-related expenses are denominated in local currency. In Argentina and Peru, our revenue, expenses, and capital expenditures, including tenant leases, ground leases, and other tower-related expenses are dominated in a mix of local currency and U.S. dollars. Our foreign currency denominated revenues and expenses are translated into U.S. dollars at average exchange rates for inclusion in our consolidated financial statements.    

For the year ended December 31, 2017, approximately 18.6% of our total cash site leasing revenue was generated by our international operations, of which 13.6% was generated in non-U.S. dollar currencies, including 12.7% which was denominated in Brazilian Reais. The exchange rates between our foreign currencies and the U.S. Dollar have fluctuated significantly in recent years and may continue to do so in the future.  For example, the Brazilian Real has historically been subject to substantial volatility and strengthened 8.7% when comparing the average rate for the years ended December 31, 2017 and 2016.  This trend has affected, and may in the future continue to affect, our reported results of operations.

Changes in exchange rates between these local currencies and the U.S. dollar will affect the recorded levels of site leasing revenue, segment operating profit, assets and/or liabilities. Volatility in foreign currency exchange rates can also affect our ability to plan, forecast and budget for our international operations and expansion efforts. 

Furthermore, we have intercompany loan agreements which permit one of our Brazilian entities to borrow amounts up to $1,250 million. As of December 31, 2017, the aggregate outstanding balance under these agreements was $560.9 million. In accordance with

ASC 830, we remeasure foreign denominated intercompany loans with the corresponding change in the balance being recorded in Other income (expense), net in our Consolidated Statements of Operations as settlement is anticipated or planned in the foreseeable future. Consequently, if the U.S. Dollar strengthens against the Brazilian Real, our results of operations would be adversely affected. For the years ended December 31, 2017 and 2016, we recorded  a $8.8 million loss and a $90.0 million gain, respectively, on the remeasurement of the intercompany loan due to changes in foreign currency exchange rates.

We may not be able to fully recognize the anticipated benefits of towers that we acquire.

A key element of our growth strategy is to increase our tower portfolio through acquisitions. We rely on our due diligenceare subject to a number of risks and uncertainties as a result of those acquisition activities. These activities may fail to achieve the towers andbenefits we expected from the representations and financial records of the sellers and other third parties to establish the anticipated revenues and expenses and whetheracquisition or the acquired towers willassets may not meet our internal guidelines for current and future potential returns. In addition,returns, particularly if we may not always have the ability to analyze and verify all information regarding title, access and other issues regarding the land underlying acquired towers.  This is particularly true in our international acquisitions of towers from wireless service providers. To the extent that these towers were acquired in individually material transactions, we may beare required to place enhancedgreater reliance on the financial and operational representations and warranties of the sellers. If (i)sellers in individually material acquisitions. The impact of these records are not complete or accurate, (ii) we do not have complete accessrisks is further enhanced in acquisitions of towers in international markets, where it may be more challenging to or use of,analyze and verify all relevant information with respect to the land underlying the acquired towers or (iii) the towers do not achieve the financial results anticipated, itassets being acquired. These risks could adversely affect our revenues and results of operations.

In addition, acquisitions which would be material in the aggregate may exacerbate the risks inherent with our growth strategy, such as (i)(1) an adverse financial impact on our overall profitability if the acquired towers do not achieve the projected financial results, (ii)(2) the impact of unanticipated costs associated with the acquisitions that may impacton our results of operations, for a period, (iii)(3) increased demands on our cash resources that may among other things, impact our ability to explore other opportunities, (iv)(4) undisclosed and assumed liabilities that we may be unable to recover, (v) increased vulnerability to general economic conditions, (vi)(5) an adverse impact on our existing customer relationships, (vii)(6) additional expenses and exposure to new regulatory, political and economic risks, if such acquisitions were in new jurisdictions and (viii)(7) diversion of managerial attention.

The process of integrating any acquired towers into our operations may result inis also subject to a number of risks and financial impacts, including unforeseen operating difficulties, and large expenditures, and may absorb significantdiversion of management attention, that would otherwise be available for the ongoing development of our business. It may also result in the loss of key customers and/or personnel, our inability to retain or timely find suitable replacements for key employees and expose usmanagement needed to operate the acquired business, and exposure to unanticipated liabilities. These risks may be exacerbated in those circumstances in which we acquireacquisitions of a material number of

towers. Further, we may not be able to retain the key employees that may be necessary to operate the business we acquire, and we may not be able to timely attract new skilled employees and management to replace them. There can be no assurance that we will be successful in integrating domestic and international acquisitions into our existing business. This is particularly true in our international acquisitions of towers from wireless service providers.

Delays or changes in the deployment or adoption of new technologies or slowing consumer adoption rates may have a material adverse effect on our growth rate.

There can be no assurances that 3G, 4G, including long-term evolution (“LTE”), advanced wireless service in the 1695-1710 MHz, 1755-1780 MHz, and 2155-2180 MHz bands (the “AWS-3” bands), or other new wireless technologies such as 5G will be deployed or adopted as rapidly as projected or that these new technologies will be implemented in the manner anticipated. The deployment of 3G in the United States experienced delays from the original projected timelines of the wireless and broadcast industries, and continued deployment of 4G could experience delays. Additionally, the demand by consumers and the adoption rate of consumers for these new technologies once deployed may be lower or slower than anticipated, particularly in certain of our international markets. These factors could have a material adverse effect on our growth rate since growth opportunities and demand for our tower space as a result of such new technologies may not be realized at the times or to the extent anticipated.

The documents governing our indebtedness contain restrictive covenants that could adversely affect our business by limiting our flexibility.

The indentures governing the 20142016 Senior Notes, the 20162020 Senior Notes, and the 20172021 Senior Notes, the Senior Credit Agreement, and the agreement for the mortgage loan underlying the Tower Securities contain restrictive covenants imposing significant operational and financial restrictions on us, including restrictions that may limit our ability to engage in acts that may be in our long-term best interests. Among other things, the covenants under each instrument limit our ability to:

•merge, consolidate or sell assets;

•make restricted payments, including pay dividends or make other distributions;

•enter into transactions with affiliates;

•enter into sale and leaseback transactions; and

•issue guarantees of indebtedness.

We are required to maintain certain financial ratios under the Senior Credit Agreement. The Senior Credit Agreement, as amended, requires SBA Senior Finance II to maintain specific financial ratios, including (1) a ratio of Consolidated Total Debt to Annualized Borrower EBITDA not to exceed 6.5 times for any fiscal quarter, (2) a ratio of Consolidated Total Debt and Net Hedge Exposure (calculated in accordance with the Senior Credit Agreement) to Annualized Borrower EBITDA for the most recently ended fiscal quarter not to exceed 6.5 times for 30 consecutive days and (3) a ratio of Annualized Borrower EBITDA to Annualized Cash Interest Expense (calculated in accordance with the Senior Credit Agreement) of not less than 2.0 times for any fiscal quarter.

Additionally, the mortgage loan relating to our Tower Securities contains financial covenants that require that the borrowers maintain, on a consolidated basis, a minimum debt service coverage ratio. To the extent that the debt service coverage ratio, as of the end of any calendar quarter, falls to 1.30 times or lower, then all cash flow in excess of amounts required to make debt service payments, to fund required reserves, to pay management fees and budgeted operating expenses and to make other payments required under the loan documents, referred to as “excess cash flow,” will be deposited into a reserve account instead of being released to the borrowers. The funds in the reserve account will not be released to the borrowers unless the debt service coverage ratio exceeds 1.30 times for two consecutive calendar quarters. If the debt service coverage ratio falls below 1.15 times as of the end of any calendar quarter, then an “amortization period” will commence and all funds on deposit in the reserve account will be applied to prepay the mortgage loan until such time that the debt service coverage ratio exceeds 1.15 times for a calendar quarter.

We are required to maintain certain financial ratios under the Senior Credit Agreement. The Senior Credit Agreement, as amended, requires SBA Senior Finance II to maintain specific financial ratios, including (1) a ratio of Consolidated Net Debt to Annualized Borrower EBITDA not to exceed 6.5 times for any fiscal quarter and (2) a ratio of Annualized Borrower EBITDA to Annualized Cash Interest Expense (calculated in accordance with the Senior Credit Agreement) of not less than 2.0 times for any fiscal quarter.

These covenants could place us at a disadvantage compared to some of our competitors which may have fewer restrictive covenants and may not be required to operate under these restrictions. Further, these covenants could have an adverse effect on our business by limiting our ability to take advantage of financing, new tower development, merger and acquisitions or other opportunities. If we fail to comply with these covenants, it could result in an event of default under our debt instruments. If any default occurs, all amounts outstanding under our outstanding notes and the Senior Credit Agreement may become immediately due and payable.

Our dependence on our subsidiaries for cash flow may negatively affect our business.

We are a holding company with no business operations of our own. Our only significant assets are, and are expected to be, the outstanding capital stock and membership interests of our subsidiaries. We conduct, and expect to continue conducting, all of our business operations through our subsidiaries. Accordingly, our ability to pay our obligations is dependent upon dividends and other distributions from our subsidiaries to us. Most of our indebtedness is owed directly by our subsidiaries, including the mortgage loan underlying the Tower Securities, the Term Loans and any amounts that we may borrow under the Revolving Credit Facility. Consequently, the first use of any cash flow from operations generated by such subsidiaries will be payments of interest and principal, if any, under their respective indebtedness. Other than the cash required to repay amounts due under our 2014 Senior Notes, 2016 Senior Notes, 2020 Senior Notes, and 20172021 Senior Notes, and funds to be utilized for stock repurchases and dividend payments, we currently expect that substantially all the earnings and cash flow of our subsidiaries will be retained and used by them in their operations, including servicing their respective debt obligations. The ability of our operating subsidiaries to pay dividends or transfer assets to us is restricted by applicable state law and contractual restrictions, including the terms of their outstanding debt instruments.

Our quarterly operating results for our site development services fluctuate and therefore we may not be able to adjust our cost structure on a timely basis with regard to such fluctuations.

The demand for our site development services fluctuates from quarter to quarter and should not be considered indicative of long-term results. Numerous factors cause these fluctuations, including:

•the timing and amount of our customers’ capital expenditures;

•the size and scope of our projects;

•the business practices of customers, such as deferring commitments on new projects until after the end of the calendar year or the customers’ fiscal year;

•delays relating to a project or tenant installation of equipment;

•seasonal factors, such as weather, holidays and vacation days and total business days in a quarter;

•the use of third party providers by our customers;

•the rate and volume of wireless service providers’ network development; and

•general economic conditions.

Although the demand for our site development services fluctuates, we incur significant fixed costs, such as maintaining a staff and office space, in anticipation of future contracts. In addition, the timing of revenues is difficult to forecast because our sales cycle may be relatively long. Therefore, we may not be able to adjust our cost structure on a timely basis to respond to the fluctuations in demand for our site development services.

The loss of the services of certain of our key personnel or a significant number of our employees may negatively affect our business.

Our success depends to a significant extent upon performance and active participation of our key personnel. We cannot guarantee that we will be successful in retaining the services of these key personnel. WeAlthough we have employment agreements with

Jeffrey A. Stoops, our President and Chief Executive Officer, Kurt L. Bagwell, our Executive Vice President and President—International, Thomas P. Hunt, our Executive Vice President, Chief Administrative Officer and General Counsel, and Brendan T. Cavanagh, our Executive Vice President and Chief Financial Officer.Officer, these agreements do not ensure that those members will continue with us in their current capacity for any particular period of time. We do not have employment agreements with any of our other key personnel. If weany of our key personnel were to lose any key personnel,leave or retire, we may not be able to find an appropriate replacement on a timely basis and our results of operations could be negatively affected. Further, the loss of a significant number of employees or our inability to hire a sufficient number of qualified employees could have a material adverse effect on our business.

Our business is subject to government regulations and changes in current or future regulations could harm our business.

We are subject to federal, state and local regulation of our business, both in the U.S. and internationally. In the U.S., both the FAA and the FCC regulate the construction, modification, and maintenance of towers and structures that support antennas used for wireless communications and radio and television broadcasts. In addition, the FCC separately licenses and regulates wireless communications equipment, wireless radio stations, and radio and television and radiobroadcast stations operating from such towers. FAA and FCC regulations govern construction, lighting, painting, and marking of towers and may, depending on the characteristics of the tower, require registration of the tower. Certain proposals to construct new towers or to modify existing towers are reviewed by the FAA to ensure that the tower will not present a hazard to air navigation. Further, as a result of our recent acquisition of a building containing a data center, we also acquired a limited number of residential apartment units and became subject to additional federal, state and local laws and regulations such as building, zoning, landlord/tenant, health and safety, and accessibility governing residential housing.

Tower owners may have an obligation to mark or paint such towers or install lighting to conform to FAA and FCC regulations and to maintain such marking, painting and lighting. Tower owners may also bear the responsibility of notifying the FAA of any lighting outages. Certain proposals to operate wireless communications and radio or television broadcast stations from towers are also reviewed by the FCC to ensure compliance with environmental impact requirements established in federal statutes, including NEPA, NHPA and ESA. Failure to comply with existing or future applicable requirements may lead to civil penalties or other liabilities and may subject us to significant indemnification liability to our customers against any such failure to comply. In addition, new regulations may impose additional costly burdens on us, which may affect our revenues and cause delays in our growth. Local regulations, including municipal or local ordinances, zoning restrictions and restrictive covenants imposed by community developers, vary greatly, but typically require tower owners to obtain approval from local officials or community standards organizations prior to tower construction or modification. Local regulations can delay, prevent, or increase the cost of new construction, co-locations, or site upgrades, thereby limiting our ability to respond to customer demand. In addition, new regulations may be adopted that increase delays or result in additional costs to us. In our international operations, the impact of these zoning, permitting and related regulations and restrictive covenants on our new builds, co-locations and operations could be exacerbated as some of these markets may lack established permitting processes for towers, have inconsistencies between national and local regulations and have other barriers to timely construction and permitting of towers.  As a result, tower construction in some of our international markets may be delayed or halted or our acquired towers may not perform as anticipated. These factors could have a material adverse effect on our future growth and operations.

Security breaches and other disruptions could compromise our information, which would cause our business and reputation to suffer.

As part of our day-to-day operations, we rely on information technology and other computer resources and infrastructure to carry out important business activities and to maintain our business records. Our computer systems, or those of our cloud or Internet-based providers, could fail on their own accord and are subject to interruption or damage from power outages, computer and telecommunications failures, computer viruses, security breaches (including through cyber-attack and data theft), errors, catastrophic events such as natural disasters and other events beyond our control. If our or our vendors’ computer systems and backup systems are compromised, degraded, damaged, or breached, or otherwise cease to function properly, we could suffer interruptions in our operations or unintentionally allow misappropriation of proprietary or confidential information (including information about our tenants or landlords). This could damage our reputation and disrupt our operations and the services we provide to customers, which could adversely affect our business and operating results. In addition, security incidents that impact our customers and other business partners could adversely affect our business and operating results. Furthermore, our investments in ancillary services and emerging technologies, including data centers and our mobile edge computing initiative, may leave us more vulnerable to security incidents, create new exposure for us to different types of security incidents or exacerbate the impact of such incidents on our business and operating results.

Our towersData privacy and protection laws are subjectevolving globally and present risks related to damageour handling of sensitive data that could result in regulatory penalties or litigation.

A portion of the activities that support our business involve collection, storage and transfer of sensitive data of our employees, tenants, ground lessors and other third parties, including residential tenants as a result of our recent data center acquisition that included a limited number of residential apartment units. In recent years there has been increased public attention regarding the protection of personal data and security of data transfers, accompanied by legislation and regulations intended to strengthen data protection and information security. The evolving nature of privacy laws in the U.S., Brazil and other countries where we have operations could impact our compliance costs in handling such data. Many data privacy regulations also grant private rights of action, including Brazil's new General Data Protection Law and certain state laws, such as California's Consumer Privacy Act. As interpretation and enforcement of these and other future data privacy regulations and industry standards evolve, we may incur costs related to litigation or regulatory penalties if we are non-compliant.

Damage from natural disasters and other unforeseen events. events could adversely affect us.

Our towers are subject to risks associated with natural disasters such as tornadoes, fires, hurricanes, and earthquakes or may collapse for any number of reasons, including structural deficiencies. In addition, we have energy sources on some of our tower sites, and any unforeseen incident may cause damage to surrounding property. We maintain insurance to cover the estimated cost of replacing damaged towers and damage to surrounding property, but these insurance policies are subject to loss limits and deductibles. We also maintain third party liability insurance, subject to loss limits and deductibles, to protect us in the event of an accident involving a tower. AAn incident involving our towers or tower accidentsites for which we are uninsured or underinsured, or damage to a significant number of our towers or surrounding property, could require us to incur significant expenditures and may have a material adverse effect on our operations or financial condition and may harm our reputation.

To the extent that we are not able to meet our contractual obligations to our customers, due to a natural disaster or other catastrophic circumstances, our customers may not be obligated or willing to pay their lease expenses; however, we may be required to continue paying our fixed expenses related to the affected tower, including expenses for ground lease expenses.leases and other property interests. If we are unable to meet our contractual obligations to our customers for a material portion of our towers, our operations could be materially and adversely affected.

We could have liability under environmental laws that could have a material adverse effect on our business, financial condition and results of operations.

Our operations, like those of other companies engaged in similar businesses, are subject to the requirements of various federal, state, local and foreign environmental and occupational safety and health laws and regulations, including those relating to the management, use, storage, disposal, emission and remediation of, and exposure to, hazardous and non-hazardous substances, materials, and wastes. As owner, lessee, or operator of numerous tower structures, we may be liable for substantial costs of remediating soil and groundwater contaminated by hazardous materials without regard to whether we, as the owner, lessee, or operator, knew of or were responsible for the contamination. We may be subject to potentially significant fines or penalties if we fail to comply with any of these requirements. The current cost of complying with these laws is not material to our financial condition or results of operations. However, the requirements of these laws and regulations are complex, change frequently, and could become more stringent in the future. It is possible that these requirements will change or that liabilities will arise in the future in a manner that could have a material adverse effect on our business, financial condition and results of operations.

We could suffer adverse tax and other financial consequences if taxing authorities do not agree with our tax positions.

We are periodically subject to a number of tax examinations by taxing authorities in the states and countries where we do business. We also have significant net operating losses (“NOLs”) in U.S. federal and state taxing jurisdictions. Generally, for U.S. federal and state tax purposes, NOLs generated prior to the 2018 tax year can be carried forward and used for up to twenty20 years, and all of our tax years will remain subject to examination until three years after our NOLs are used or expire. NOLs generated starting in the 2018 tax year can be carried forward indefinitely but are subject to the 80% utilization limitation. We expect that we will continue to be subject to tax examinations in the future. In addition, U.S. federal, state and local, as well as international, tax laws and regulations are extremely complex and subject to varying interpretations. If our tax benefits, including from our use of NOLs or other tax attributes, are challenged successfully by a taxing authority, we may be required to pay additional taxes or penalties, or make additional distributions, which could have a material adverse effect on our business, results of operations and financial condition.

Our issuance of equity securities and other associated transactions may trigger a future ownership change which may negatively impact our ability to utilize NOLs in the future.

The issuance of equity securities and other associated transactions may increase the chance that we will have a future ownership change under Section 382 of the Internal Revenue Code of 1986.1986 (“Code”). We may also have a future ownership change, outside of our control, caused by future equity transactions by our current shareholders. Depending on our market value at the time of such future ownership change, an ownership change under Section 382 could negatively impact our ability to utilize our NOLs and could result in us having to make additional cash distributions.

Our costs could increase and our revenues could decrease due to perceived health risks from RF energy.

The U.S. government imposesand other foreign governments impose requirements and other guidelines relating to exposure to RF energy. Exposure to high levels of RF energy can cause negative health effects. The potential connection between exposure to low levels of RF energy and certain negative health effects, including some forms of cancer, has been the subject of substantial study by the scientific community in recent years. According to the FCC, the results of these studies to date have been inconclusive. However, public perception of possible health risks associated with cellular and other wireless communications media could slow the growth of wireless companies, which could in turn slow our growth. In particular, negative public perception of, and regulations regarding, health risks could cause a decrease in the demand for wireless communications services. Moreover, if a connection between exposure to low levels of RF energy and possible negative health effects, including cancer, were demonstrated, we could be subject to numerous claims. Our current policies provide no coverage for claims based on RF energy exposure. If we were subject to claims relating to exposure to RF energy, even if such claims were not ultimately found to have merit, our financial condition could be materially and adversely affected.

The recently adopted US tax legislation may result in additional tax liabilities that may affectrecent COVID-19 pandemic has significantly impacted worldwide economic conditions and could have a material adverse effect on our future results and profitability.

On December 22, 2017, the U.S. government enacted comprehensive tax legislation, commonly referred to as the Tax Cuts and Jobs Act (the “Tax Act”), that significantly revises the U.S. tax code by, among other things, lowering the corporate income tax rate from a top marginal rate of 35% to a flat 21%, imposing a mandatory one-time deemed repatriation of foreign earnings (commonly referred to as the “transition tax”), limiting deductibility of interest expense and certain executive compensation and implementing a territorial tax system.

The SEC staff acknowledged the challenges companies face incorporating the effects of the Tax Act by their financial reporting deadlines. In response, Staff Accounting Bulletin No. 118 (“SAB 118”) was issued on December 22, 2017, regarding application of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 740, Income Taxes (“ASC Topic 740”), specifically to the Tax Act.  SAB 118 addresses the application of US GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed in reasonable detail to complete accounting for certain income tax effects of the Tax Act.

The Tax Act impacted our consolidatedbusiness operations, results of operations, duringcash flows and financial condition.

In December 2019, a novel strain of coronavirus, COVID-19, was identified in China. This virus continues to spread globally and in March 2020, the fourth quarterWorld Health Organization declared COVID-19 a pandemic. In December 2020, the first COVID-19 vaccine was released to the U.S. public for distribution. Public and mayprivate sector responsive measures, such as the imposition of travel restrictions, quarantines, adoption of remote working, and suspension of non-essential business and government services, could impact our consolidated results of operations in future periods.  In particular, the transition tax resulted in a one-time income inclusion of $52.4 million related to previously unremitted earnings of certain non-U.S. subsidiaries, which we will elect to include in income over the next eight tax years. The inclusion will be offset by our existing NOLs to the extent possible during the eight-year recognition period.operations. In addition, we recorded a one-time reductionCOVID-19 continues to our deferred tax assetsignificantly impact worldwide economic conditions, including negatively impacting economic growth and offsetting valuation allowancecreating disruption and volatility in the amountglobal financial and capital markets. Among other things, COVID-19 and the responsive measures that have been adopted may adversely affect:

the ability of $31.5 million; $19.2 million relatedour suppliers and vendors to provide products and services to us;

demand for our wireless infrastructure;

our ability to build new towers or the reductionability of the U.S. corporate tax rate and $12.3 million relatedour customers to theinstall new limitationsantennas on the deductibilityan existing tower, including as a result of executive compensation.  These amounts represent our provisional estimate of the relevant charges, but will be subject to adjustment as we finalize the relevant computations and as additional IRS rules and guidance on the Tax Act provisions are adopted. Since the Tax Act was passed latedelays or suspensions in the fourth quarterissuance of 2017,permits or other authorizations needed to increase the number of our tenants or amend our tenant leases; 

interest rates and ongoing guidancethe overall availability and accounting interpretation are expected over cost of capital, which could affect our ability to continue to grow our asset portfolio or pursue new business initiatives;

the next 12 months, we consider financial condition of wireless service providers;

the accountingability and willingness of wireless service providers to maintain or increase capital expenditures;

the Transition Tax, GILTI, Section 162(m) adjustment, state taxes,ability of our tenants to make lease payments on a timely basis; and other items

the willingness of our tenants to be incomplete due to the forthcoming guidance and our ongoing analysis of final year-end data and tax positions. We expect to complete our analysis within the measurement period in accordance with SAB 118.  Any material revisions in our computations could adversely affectrenew their existing leases for additional terms.

In addition, our results of operations in future periods. 

In addition, manymay be negatively affected by foreign currency adjustments resulting from the COVID-19 pandemic, including the recent strengthening of the provisionsU.S. Dollar against the currencies in certain international markets in which we operate. The extent of the Tax Actimpact of COVID-19 on our business operations, results of operations, cash flows, and financial condition, will require guidance throughdepend on future developments, including the issuance of Treasury regulations in order to assess their effect. There may be a substantial delay before such regulations are promulgated, increasing the uncertainty as to the ultimate effectduration and spread of the statutory amendmentspandemic and related government restrictions, all of which are uncertain and cannot be predicted. Additionally, if the COVID-19 pandemic results in a global recession, the negative impacts of the pandemic on us. Future regulatoryour operating results may worsen or administrative guidance may also have an adverse impact on us or our shareholders.be prolonged.

Risks Related to Our Status as a REIT

Complying with the REIT requirements may cause us to liquidate assets or hinder our ability to pursue otherwise attractive asset acquisition opportunities.

To qualify as a REIT for federal income tax purposes, we must continually satisfy tests concerning, among other things, the nature and diversification of our assets, the sources of our income and the amounts we distribute to our shareholders. For example, to qualify as a REIT, we must ensure that, at the end of each calendar quarter, at least 75% of the value of our assets consists of cash, cash items, government securities and “real estate assets” (as defined in the Code), including towers and certain mortgage loans and securities. The remainder of our investments (other than government securities, qualified real estate assets and securities issued by a taxable REIT subsidiary (“TRS”)) generally cannot include more than 10% of the outstanding voting securities of any one issuer or more than 10% of the total value of the outstanding securities of any one issuer. In addition, in general, no more than 5% of the value of our total assets (other than government securities, qualified real estate assets and securities issued by a TRS) can consist of the securities of any one issuer, and no more than 25% (for taxable years beginning on or before December 31, 2017) or 20% (for taxable years beginning after December 31, 2017) of the value of our total assets can be represented by securities of one or more TRSs. If we fail to comply with these requirements at the end of any calendar quarter, we must correct the failure within 30 days after the end of the calendar quarter or qualify for certain statutory relief provisions to avoid losing our REIT qualification and suffering adverse tax consequences. As a result, we may be required to liquidate assets.

In addition to the asset tests set forth above, to qualify and be subject to tax as a REIT, we will generally be required to distribute at least 90% of our REIT taxable income after the utilization of any available NOLs (determined without regard to the dividends paid deduction and excluding net capital gain) each year to our shareholders. Our determination as to the timing or amount of future dividends will be based on a number of factors, including investment opportunities around our core business and the availability of our existing NOLs. To the extent that we satisfy the 90% distribution requirement, but distribute less than 100% of our REIT taxable income (after the application of available NOLs, if any), we will be subject to U.S. federal corporate income tax on 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 our shareholders for a calendar year is less than a minimum amount specified under the Code. These distribution requirements could hinder our ability to pursue otherwise attractive asset acquisition opportunities. Furthermore, our ability to compete for acquisition opportunities in domestic and international markets may be adversely affected if we need, or require, the target company to comply with certain REIT requirements. These actions could have the effect of reducing our income, amounts available for distribution to our shareholders and amounts available for making payments on our indebtedness.

Qualifying as a REIT involves highly technical and complex provisions of the Code. If we fail to qualify as a REIT or fail to remain qualified as a REIT, to the extent we have REIT taxable income and have utilized our NOLs, we will be subject to U.S. federal income tax as a regular corporation and could face a substantial tax liability, which would reduce the amount of cash available for distribution to our shareholders.

Qualification as a REIT involves the application of highly technical and complex Code provisions for which only limited judicial and administrative authorities exist. Even a technical or inadvertent violation could jeopardize our REIT qualification. Our qualification as a REIT will depend on our satisfaction of certain asset, income, organizational, distribution, shareholder ownership and other requirements on a continuing basis.

We received an opinion of our special REIT tax counsel with respect to our qualification as a REIT. Investors should be aware, however, that opinions of counsel are not binding on the IRS or any court. The opinion represents only the view of such counsel based on its review and analysis of existing law and on certain representations as to factual matters and covenants made by us, including representations relating to the values of our assets and the sources of our income. The opinion is expressed as of the date issued. Our qualification as a REIT will depend on our satisfaction of certain asset, income, organizational, distribution, shareholder ownership and other requirements on a continuing basis. Our ability to satisfy the asset tests depends upon our analysis of the characterization and fair market values of our assets, some of which are not susceptible to a precise determination, and for which we will not obtain independent appraisals.

If we fail to qualify as a REIT in any taxable year, to the extent we have REIT taxable income and have utilized our NOLs, we would be subject to U.S. federal income tax, including any applicable alternative minimum tax on our taxable income at regular corporate rates, and dividends paid to our shareholders would not be deductible by us in computing our taxable income. Any resulting corporate tax liability could be substantial and would reduce the amount of cash available for distribution to our shareholders, which in turn could have an adverse impact on the value of our common stock. Unless we were entitled to relief under certain provisions of the Code, we also would be disqualified from re-electing to be taxed as a REIT for the four taxable years following the year in which we failed to qualify as a REIT. If we fail to qualify for taxation as a REIT, we may need to borrow additional funds or liquidate assets to pay any additional tax liability. Accordingly, funds available for investment and making payments on our indebtedness would be reduced.

We may be required to borrow funds, sell assets, or raise equity to satisfy our REIT distribution requirements.

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 of taxable income and the actual receipt of cash or the effect of nondeductible capital expenditures, the creation of reserves or required debt or amortization payments. If we do not have other funds available in these situations, we may need to borrow funds, sell assets or raise equity, even if the then-prevailing market conditions are not favorable for these borrowings,

sales or offerings, to enable us to satisfy the REIT distribution requirement and to avoid U.S. federal corporate income tax and the 4% excise tax in a particular year. These alternatives could increase our costs and our leverage, decrease our Adjusted Funds From Operations per share or require us to distribute amounts that would otherwise be invested in future acquisitions or stock repurchases.

Thus, compliance with the REIT requirements may hinder our ability to grow, which could adversely affect the value of our common stock. Furthermore, compliance with the REIT distribution requirements may increase the financing we need to fund capital expenditures, future growth, or expansion initiatives, which would increase our total leverage.

Covenants specified in our current and future debt instruments may limit our ability to make required REIT distributions.

The Senior Credit Agreement, the mortgage loan agreement related to our securitization transactions and the indentures governing our 2014 Senior Notes,  2016 Senior Notes, 2020 Senior Notes, and 20172021 Senior Notes contain certain covenants that could limit our ability to make distributions to our shareholders. Under the Senior Credit Agreement, our subsidiaries may make distributions to us to satisfy our REIT distribution requirements and additional amounts to distribute up to 100% of our REIT taxable income, so long as SBA Senior Finance II’s ratio of Consolidated TotalNet Debt to Annualized Borrower EBITDA does not exceed 6.5 times for any fiscal quarter. In addition, under the mortgage loan agreement related to our securitization transactions, or Securitization, a failure to comply with the Debt Service Coverage Ratio in that agreement could prevent our borrower subsidiaries from distributing any excess cash from the operation of their towers to us. Finally, while the indentures governing the 2014 Senior Notes,  2016 Senior Notes, 2020 Senior Notes, and 20172021 Senior Notes permit us to make distributions to our shareholders to the extent such distributions are necessary to maintain our status as a REIT or to avoid entity level taxation, this authority is subject to the conditions that no default or event of default exists or would result therefrom and that the obligations under the 2014 Senior Notes,  2016 Senior Notes, 2020 Senior Notes, or 20172021 Senior Notes, as applicable, have not otherwise been accelerated.

If these limitslimitations prevent us from satisfying our REIT distribution requirements, we could fail to qualify for taxation as a REIT. If these limitslimitations do not jeopardize our qualification for taxation as a REIT but do nevertheless prevent us from distributing 100% of our REIT taxable income, we will be subject to U.S. federal corporate income tax, and potentially the nondeductible 4% excise tax, on the retained amounts.

Our payment of cash distributions in the future is not guaranteed and the amount of any future cash distributions may fluctuate, which could adversely affect the value of our Class A common stock.

REITs are required to distribute annually at least 90% of their REIT taxable income (determined before the deduction for dividends paid and excluding any net capital gain). As of December 31, 2017,  $956.72020, $651.1 million of theour federal NOLs are attributes of the REIT. We may use these NOLs to offset our REIT taxable income, and thus any required distributions to shareholders may be reduced or eliminated until such time as the NOLs have been fully utilized.utilized, which may adversely affect the market value of our Class A common stock. The Internal Revenue Code places limitations upon the future availability of NOLs based upon changes in our equity. If these occur, our ability to offset future income with existing NOLs may be limited. We currently expect that we will utilize available NOLs to reduce all or a portion of our REIT taxable income and therefore we may not initially make any distributions, which may adversely affect the market value of our Class A common stock.

The amount of future distributions will be determined, from time to time, by theour Board of Directors to balance our goal of increasing long-term shareholder value and retaining sufficient cash to implement our current capital allocation policy, which prioritizes investment in quality assets that meet our return criteria, and then stock repurchases, when we believe our stock price is below its intrinsic value. The actual timing and amount of distributions will be as determined and declared by theour Board of Directors and will depend on, among other factors, our NOLs, our financial condition, earnings, debt covenants and other possible uses of such funds. Consequently, our future distribution levels may fluctuate.

Certain of our business activities may be subject to corporate level income tax and foreign taxes, which would reduce our cash flows, and would have potential deferred and contingent tax liabilities.

We may be subject to certain federal, state, local and foreign taxes on our income and assets, including alternative minimum taxes, taxes on any undistributed income and state, local or foreign income, franchise, property and transfer taxes. In addition, we 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 more relief provisions under the Code to maintain qualification for taxation as a REIT. In addition, we may incur a 100%

excise tax on transactions with a TRS if they are not conducted on an arm’s length basis. Any of these taxes would decrease our earnings and our available cash.

Our TRS assets and operations also will continue to be subject, as applicable, to federal and state corporate income taxes and to foreign taxes in the jurisdictions in which those assets and operations are located. If we continue our international expansion, we

may have additional TRS assets and operations subject to such taxes. Any of these taxes would decrease our earnings and our available cash.

We will also be subject to a federal corporate level tax at the highest regular corporate rate (35% in 2017 and 21% as of January 1, 2018) on the gain recognized from a sale of assets occurring during our first five years as a REIT, up to the amount of the built-in gain that existed on January 1, 2016, which is based on the fair market value of those assets in excess of our tax basis in those assets as of January 1, 2016. Gain from a sale of an asset occurring after the specified period ends will not be subject to this corporate level tax. We currently do not expect to sell any asset if the sale would result in the imposition of a material tax liability. We cannot, however, assure you that we will not change our plans in this regard.

Our use of TRSs may cause us to fail to qualify as a REIT.

The net income of our TRSs is not required to be distributed to us, and such undistributed TRS income is generally not subject to our REIT distribution requirements. However, if the accumulation of cash or reinvestment of significant earnings in our TRSs causes the fair market value of our securities in those entities, taken together with other non-qualifying assets, to represent more than 25% of the fair market value of our assets, or causes the fair market value of our TRS securities alone to represent more than 25% (for20% (25% for taxable years beginning on or before December 31, 2017) or 20% (for taxable years beginning afterprior to December 31, 2017) of the value of our total assets, in each case, as determined for REIT asset testing purposes, we would, absent timely responsive action, fail to qualify as a REIT. If we continue our international expansion, we may have increased net income from TRSs, which may cause us to rise above these thresholds.

Legislative or other actions affecting REITs could have a negative effect on us.

The rules dealing with U.S. federal income taxation are constantly under review by persons involved in the legislative process and by the IRS and the Treasury. Changes to the tax laws or interpretations thereof, with or without retroactive application, could materially and adversely affect our investors or us. We cannot predict how changes in the tax laws might affect our investors or us. New legislation, U.S. Treasury Regulations, administrative interpretations or court decisions could significantly and negatively affect our ability to qualify as a REIT or the U.S. federal income tax consequences to our investors and us of such qualification.

Our Board’s ability to revoke our REIT qualification, without shareholder approval, may cause adverse consequences to our shareholders.

Our articles of incorporation provide that our Board of Directors may revoke or otherwise terminate our REIT election, without the approval of our shareholders, if it determines that it is no longer in our best interests to continue to qualify as a REIT. If we cease to be a REIT, we will not be allowed a deduction for dividends paid to shareholders, if any, in computing our taxable income, and to the extent we have taxable income and have utilized our NOLs, we will be subject to U.S. federal income tax at regular corporate rates and state and local taxes, which may have adverse consequences on our total return to our shareholders.

We have limited experiencebegan operating as a REIT in 2016, which may adversely affect our financial condition, results of operations, cash flow, per share trading price of our common stock and ability to satisfy debt service obligations.

We have limited experiencebegan operating as a REIT in 2016 and as a result, we may not be able to continue to operate successfully as a REIT. In addition, we will beare required to implementmaintain substantial control systems and procedures in order to maintain our status as a REIT. As a result, we may incurWe have also incurred additional legal, accounting and other expenses that we havedid not previously incurred, which could be significant,incur prior to operating as a REIT and our management and other personnel may need to devotehave devoted additional time to comply with these rules and regulations and controls required for continued compliance with the Code.  These costs and time commitments could be substantially more than we currently expect. Therefore,factors may adversely affect our historical combined consolidated financial statements may not be indicative of our future costs and performance as a REIT. If our performance is adversely affected, it could affect our financial condition, results of operations, cash flow and ability to satisfy our debt service obligations.

The historical market price of our Class A common stock prior to our REIT conversion may not be indicative of the market price of our Class A common stock following our REIT conversion.

The historical market price of our Class A common stock prior to our REIT conversion, which commenced with our taxable year ending December 31, 2016, may not be indicative of how the market values our Class A common stock following our REIT

conversion because of the change in our organization from a taxable C corporation to a REIT. Although we do not currently anticipate commencing distributions until a future date, the stock price of REIT securities have historically been affected by changes in market interest rates as investors evaluate the annual yield from distributions on the entity’s common stock as compared to yields on other financial instruments. In addition, the market price of our Class A common stock may be affected by the economic and market perception of REIT securities as well as general market conditions.

Dividends payable by REITs do not qualify for the reduced tax rates available for some dividends.

The maximum U.S. federal income tax rate applicable to income from “qualified dividends” payable to U.S. shareholders that are individuals, trusts and estates is currently 20%. Dividends payable by REITs, however, generally are not eligible for the reduced rates applicable to qualified dividends. Although these rules do not adversely affect the taxation of REITs, the more favorable rates applicable to regular corporate qualified dividends could cause investors who are individuals, trusts and estates to perceive investments in REITs to be relatively less attractive than investments in the stocks of non-REIT corporations that pay dividends, which could adversely affect the value of the stock of REITs, including our common stock. REIT ordinary income distributions are generally eligible for a 20% deduction to the extent distributed out of the REIT’s taxable income.

Risks Related to Ownership of our Class A Common Stock

The REIT-related ownership and transfer restrictions may restrict or prevent our shareholders from engaging in certain transfers of our common stock.

In order for us to satisfy the requirements for REIT qualification, no more than 50% in value of all classes or series of our outstanding shares of stock may be owned, beneficially or constructively, by five5 or fewer individuals (as defined in the Code to include certain entities) at any time during the last half of each taxable year (other than the first year for which an election to be subject to tax

as a REIT has been made). In addition, our capital stock must be beneficially owned by 100 or more persons during at least 335 days of a taxable year of 12 months or during a proportionate part of a shorter taxable year (other than the first year for which an election to be taxed as a REIT has been made). Our articles of incorporation contain REIT-related ownership and transfer restrictions that generally restrict shareholders from owning more than 9.8%, by value or number of shares, whichever is more restrictive, of our outstanding shares of Class A common stock, or 9.8% in aggregate value of the outstanding shares of all classes and series of our capital stock. Under applicable constructive ownership rules, any shares of stock owned by certain affiliated owners generally would be added together for purposes of the ownership limits. These ownership and transfer restrictions could have the effect of delaying, deferring or preventing a transaction or a change in control that might involve a premium price for our capital stock or otherwise be in the best interest of our shareholders.

Future sales of our Class A common stock in the public market or the issuance of other equity may cause dilution or adversely affect the market price of our Class A common stock and our ability to raise funds in new equity or equity-related offerings.

Sales of a substantial number of shares of our Class A common stock or other equity-related securities in the public market, including sales by any selling shareholder, could depress the market price of our Class A common stock and impair our ability to raise capital through the sale of additional equity securities.

Our articles of incorporation, our bylaws and Florida law provide for anti-takeover provisions that could make it more difficult for a third party to acquire us.

Provisions of our articles of incorporation, our bylaws and Florida law could make it more difficult for a third party to acquire us, even if doing so would be beneficial to our shareholders. These provisions, alone or in combination with each other, may discourage transactions involving actual or potential changes of control, including transactions that otherwise could involve payment of a premium over prevailing market prices to holders of our Class A common stock, or could limit the ability of our shareholders to approve transactions that they may deem to be in their best interests.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None.

ITEM 2. PROPERTIES

We own our headquarters in Boca Raton, Florida where we currently have approximately 160,000 square feet of office space. We also own or have entered into long-term leases for international and regional locations convenient for the management and operation of our site leasing activities, and in certain site development office locations where we expect our activities to be longer-term. We open and close project offices from time to time in connection with our site development business. We believe our existing facilities are adequate for our current and planned levels of operations and that additional office space suited for our needs is reasonably available in the markets within which we operate.

Our interests in towers and the land beneath them are comprised of a variety of fee interests, leasehold interests created by long-term lease agreements, perpetual easements, easements, licenses, rights-of-way, and other similar interests. As of December 31, 2017,2020, approximately 70%71% of our tower structures were located on parcels of land that we own, land subject to perpetual easements, or parcels of land that have an interest that extends beyond 20 years. The average remaining life under our ground leases and other property interests, including renewal options under our control, is 3335 years. In rural areas, support for our towers, equipment shelters, and related equipment requires a tract of land typically up to 10,000 square feet. Less than 2,500 square feet is required for a monopole or self-supporting tower of the kind typically used in metropolitan areas for wireless communications towers. Ground leases and other property interests are generally for an initial term of five years or more with five or more additional automaticmultiple renewal periods, of five years, for a total of thirty30 years or more.

Most of our towers have significant capacity available for additional antennas. We measure the available capacity of our existing facilities to support additional tenants and generate additional lease revenue by assessing several factors, including tower height, tower type, wind loading, environmental conditions, existing equipment on the tower and zoning and permitting regulations in effect in the jurisdiction where the tower is located. As of December 31, 2017,2020, we had an average of 1.71.8 tenants per tower structure.

ITEM 3. LEGAL PROCEEDINGS

We are involved in various legal proceedings relating to claims arising in the ordinary course of business. We do not believe that the ultimate resolution of these matters will have a material adverse effect on our business, financial condition, results of operations or liquidity.

ITEM 4. MINE SAFETY DISCLOSURE

Not Applicable.

PART II

ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Market for our Class A Common Stock

Our Class A common stock commenced trading under the symbol “SBAC” on The NASDAQ National Market System on June 16, 1999. We now trade on the NASDAQ Global Select Market, a segment of the NASDAQ Global Market, formally known as the NASDAQ National Market System.

The following table presents the high and low sales price for our Class A common stock for the periods indicated:

As of February 21, 2018,18, 2021, there were 67277 record holders of our Class A common stock.

Dividends

Dividends

We have never paid a dividend on any class of common stock.  As a REIT, we are required to distribute annually at least 90% of our REIT taxable income after the utilization of any available NOLs (determined before the deduction for dividends paid and excluding any net capital gain). As of December 31, 2017, $956.72020, $651.1 million of the federal NOLs are attributes of the REIT. We may use these NOLs to offset our REIT taxable income, and thus any required distributions to shareholders may be reduced or eliminated until such time as our NOLs have been fully utilized. The amount of future distributions will be determined, from time to time, by the boardour Board of directorsDirectors to balance our goal of increasing long-term shareholder value and retaining sufficient cash to implement our current capital allocation policy, which prioritizes investment in quality assets that meet our return criteria, and then stock repurchases when we believe our stock price is below its intrinsic value. The actual amount, timing and frequency of future dividends, will be at the sole discretion of the boardour Board of directorsDirectors and will be declared based upon various factors, many of which are beyond our control.

Issuer Purchases of Equity Securities

The following table presents information related to our repurchases of Class A common stock during the fourth quarter of 2017:2020:

(1)On November 2, 2020, our Board of Directors authorized a new $1.0 billion stock repurchase plan, replacing the prior plan authorized on July 29, 2019 which had $124.3 million remaining from the previous authorization. This new plan authorizes the purchase, from time to time, of up to $1.0 billion of our outstanding Class A common stock through open market repurchases in compliance with Rule 10b-18 under the Exchange Act and/or in privately negotiated transactions at management’s discretion based on market and business conditions, applicable legal requirements and other factors. Shares repurchased will be retired. The new plan has no time deadline and will continue until otherwise modified or terminated by our Board of Directors at any time in its sole discretion. As of the date of this filing, we had $500.0 million remaining under the current authorized stock repurchase plan.

ITEM 6. SELECTED FINANCIAL DATARESERVED

The following table sets forth selected historical financial data as of and for each of the five years in the period ended December 31, 2017. The financial data for the fiscal years ended 2017,  2016,  2015,  2014, and 2013 have been derived from our audited consolidated financial statements. You should read the information set forth below in conjunction with our “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and our consolidated financial statements and the related notes to those consolidated financial statements included in this Form 10-K.