AMERICAN TOWER CORP /MA/ (AMT) Business

ITEM 1. BUSINESS

Overview

We are one of the largest global real estate investment trusts and a leading independent owner, operator and developer of multitenant communications real estate. Our primary business is the leasing of space on communications sites to wireless service providers, radio and television broadcast companies, wireless data providers, government agencies and municipalities and tenants in a number of other industries. We refer to this business, inclusive of our data center business discussed below, as our property operations, which accounted for 97% of our total revenues for the year ended December 31, 2025. We also offer tower-related services in the United States, which we refer to as our services operations. These services include site application, zoning and permitting, structural and mount analyses, and construction management services, together with program management offerings that support customer deployment needs from project scoping through construction. Our services operations primarily support our site leasing business, including the addition of new tenants and equipment on our sites. Our customers include our tenants, licensees and other payers.

Since inception, we have grown our communications real estate portfolio through acquisitions, long-term lease arrangements and site development. Our portfolio primarily consists of towers that we own and towers that we operate pursuant to long-term lease arrangements, as well as distributed antenna system (“DAS”) networks, which provide seamless coverage solutions in certain in-building and outdoor wireless environments. In addition to the communications sites in our portfolio, we manage rooftop and tower sites for property owners under various contractual arrangements. We also hold other telecommunications infrastructure, fiber and property interests that we lease primarily to communications service providers and third-party tower operators, and, as discussed further below, we hold a portfolio of highly interconnected data center facilities and related assets in the United States that we provide for the leasing of space primarily to enterprises, network operators, cloud providers and supporting service providers.

As of December 31, 2025, our communications real estate portfolio of 149,686 communications sites included 42,224 communications sites in the U.S. & Canada, 27,857 communications sites in Africa & APAC (as defined below), 32,524 communications sites in Europe and 47,081 communications sites in Latin America, as well as (i) urban telecommunications assets in Argentina, Brazil, Colombia and Spain, (ii) other property interests in Canada and the United States and (iii) 30 operating data center facilities across eleven markets in the United States.

We operate as a real estate investment trust for U.S. federal income tax purposes (“REIT”). Accordingly, we generally are not required to pay U.S. federal income taxes on income generated by our REIT operations, including the income derived from leasing space on our towers and in our data centers, as we receive a dividends paid deduction for distributions to stockholders that offsets our REIT taxable income and gains. However, we remain obligated to pay U.S. federal income taxes on earnings from our domestic taxable REIT subsidiaries (“TRSs”). In addition, our international assets and operations, regardless of their classification for U.S. tax purposes, continue to be subject to taxation in the jurisdictions where those assets are held or those operations are conducted.

The use of TRSs enables us to continue to engage in certain businesses and jurisdictions while complying with REIT qualification requirements. We may, from time to time, change the election of previously designated TRSs to be included as part of the REIT. As of December 31, 2025, our REIT-qualified businesses included our U.S. tower leasing business, a majority of our U.S. DAS networks business, our Services and Data Centers segments, as well as most of our operations in Canada, Costa Rica, France, Germany, Ghana, Kenya, Mexico, Nigeria, South Africa, Spain and Uganda.

We report our results in six segments: U.S. & Canada property (which includes all assets in the United States and Canada, other than our data center facilities and related assets), Africa & Asia-Pacific (“APAC”) property, Europe property, Latin America property, Data Centers and Services.

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Products and Services

Property Operations

Our property operations accounted for 97%, 98% and 99% of our total revenues for the years ended December 31, 2025, 2024 and 2023, respectively. Our revenue is primarily generated from tenant leases. Within our tower leasing operations, our tenants lease space on our communications real estate, where they install and maintain their equipment. Rental payments vary considerably depending upon numerous factors, including, but not limited to, amount, type and position of tenant equipment on the tower, remaining tower capacity and tower location. Our costs typically include ground rent (which is primarily fixed under long-term lease agreements with annual cost escalations) and power and fuel costs, some or all of which may be passed through to our tenants, as well as property taxes and repair and maintenance expenses. Our property operations have generated consistent growth in revenue and typically have low cash flow volatility due to the following characteristics:

•Long-term tenant leases with contractual rent escalations. In general, our tenant leases for our communications sites with wireless carriers have initial non-cancellable terms of five to ten years with multiple renewal terms, with provisions that periodically increase the rent due under the lease, typically annually, based on a fixed escalation percentage (averaging approximately 3% in the United States) or an inflationary index in most of our international markets, or a combination of both. Based upon foreign currency exchange rates and the tenant leases in place as of December 31, 2025, we expect to generate over $54 billion of non-cancellable tenant lease revenue over future periods, before the impact of straight-line lease accounting.

•Consistent demand for our sites. As a result of rapidly growing usage of mobile data and other wireless services and the corresponding wireless industry capital spending trends in the markets we serve, we anticipate consistent demand for our communications sites. We believe that our global asset base positions us well to benefit from the increasing proliferation of advanced wireless devices and the increasing usage of high bandwidth applications on those devices. We have the ability to add new tenants and new equipment for existing tenants on our sites, which typically results in incremental revenue and modest incremental costs. Our site portfolio and our established tenant base provide us with a solid platform for new business opportunities, which has historically resulted in consistent and predictable organic revenue growth.

•High lease renewal rates. Our tenants tend to renew leases because suitable alternative sites may not exist or be available and repositioning a site in their network may be expensive and may adversely affect network quality. We define churn as tenant billings lost when a tenant cancels or does not renew its lease or, in limited circumstances, when the lease rates on existing leases are reduced. We derive our churn rate for a given year by dividing our tenant billings lost on this basis by our prior-year tenant billings. During the year ended December 31, 2025, churn was approximately 2% of our tenant billings, primarily driven by churn in our U.S. & Canada property segment.

•High operating margins. Incremental operating costs associated with adding new tenants or equipment to an existing communications site are typically relatively minimal. Therefore, as tenants or equipment are added, the substantial majority of incremental revenue flows through to gross margin and operating profit. In addition, in many of our international markets, certain expenses, such as ground rent or power and fuel costs, are reimbursed or shared by our tenant base.

•Low maintenance capital expenditures. On average, we require relatively low amounts of annual capital expenditures to maintain our communications sites.

Our property business includes the operation of communications sites and managed networks, the leasing of property interests and, in select markets, the operation of fiber, the operation of data centers and the provision of backup power through shared generators and power solutions. Our presence in a number of markets at different relative stages of wireless development provides us with significant diversification and long-term growth potential. Our property segments accounted for the following percentage of consolidated total revenue for the years ended December 31,:

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(1)    For the years ended December 31, 2024 and 2023, excludes the operating results of our subsidiaries, ATC Asia Pacific Pte. Ltd. and ATC Telecom Infrastructure Private Limited (“ATC TIPL”), which are reported as discontinued operations. See note 21 to our consolidated financial statements included in this Annual Report (“Note 21”) for further discussion.

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Communications Sites. Approximately 82%, 87% and 88% of revenue in our property segments was attributable to our communications sites, excluding data center facilities and related assets, DAS networks and fiber, for the years ended December 31, 2025, 2024 and 2023, respectively.

We lease space on our communications sites to tenants providing a diverse range of communications services, including cellular voice and data, broadcasting, mobile video and a number of other applications. In addition, in many of our international markets, we receive pass-through revenue from our tenants to cover certain costs, including power and fuel costs and ground rent. Our top tenants by revenue for each property segment are as follows for the year ended December 31, 2025:

•U.S. & Canada: AT&T Inc. (“AT&T”); T-Mobile US, Inc. (“T-Mobile”); and Verizon Communications Inc. (“Verizon Wireless”) accounted for an aggregate of 85% of U.S. & Canada property segment revenue.

•Africa & APAC: Bharti Airtel Limited (“Airtel”); and MTN Group Limited (“MTN”) accounted for an aggregate of 81% of Africa & APAC property segment revenue.

•Europe: Telefónica S.A. (“Telefónica”) accounted for an aggregate of 70% of Europe property segment revenue.

•Latin America: América Móvil; AT&T; Telefónica; and TIM S.p.A. accounted for an aggregate of 71% of Latin America property segment revenue.

Accordingly, we are subject to certain risks, as set forth in Item 1A of this Annual Report under the caption “Risk Factors—A substantial portion of our current and projected future revenue is derived from a small number of customers, and we are sensitive to adverse changes in the creditworthiness and financial strength of our customers.” In addition, we are subject to risks related to our international operations, as set forth under the caption “Risk Factors—Our foreign operations are subject to economic, political and other risks that could materially and adversely affect our revenues or financial position, including risks associated with fluctuations in foreign currency exchange rates.”

Data Centers and Related Assets, Managed Networks, Other Telecommunications Assets, Property Interests and Shared Generators and Power Solutions. In addition to our communications sites, we also own and operate several types of managed network solutions, provide communications site management services to third parties, manage and lease property interests under carrier or other third-party communications sites, operate data center facilities and related assets, operate other telecommunications assets and provide back-up power sources and power solutions to tenants at our sites. The balance of our property segment revenue not attributable to our communications sites was attributable to these items.

•Data Centers and Related Assets. We own and operate data center facilities and related assets in the United States, which consist of specialized and secure buildings that house networking, storage and communications technology infrastructure, including servers, storage devices, switches, routers and fiber optic transmission equipment. These buildings are designed to provide the power, cooling and network connectivity necessary to efficiently operate this equipment. Data centers located at points where many communications networks converge can also function as interconnection hubs where customers are able to connect to multiple networks, cloud companies and other service providers to exchange traffic and interoperate with each other.

•Managed Networks. We own and operate DAS networks in the United States and certain international markets. We obtain rights from property owners to install and operate in-building DAS networks, and we grant rights to wireless service providers to attach their equipment to our installations. We also offer a small portfolio of outdoor DAS networks as a complementary shared infrastructure solution for our tenants in the United States and in certain international markets. Typically, we have designed, built and operated our outdoor DAS networks in areas in which zoning restrictions or other barriers may prevent or delay deployment of more traditional wireless communications sites, such as macro tower sites. We also hold lease rights and easement interests on rooftops capable of hosting communications equipment in locations where towers are generally not a viable solution based on area characteristics. In addition, we provide management services to property owners in the United States who elect to retain full rights to their property while simultaneously marketing the rooftop for wireless communications equipment installation. As the demand for advanced wireless services in urban markets evolves, we continue to evaluate a variety of infrastructure solutions, including small cells and other network architectures that may support our tenants’ networks in these areas.

•Other Telecommunications Assets. We own and operate other telecommunications assets, including fiber and related assets, in certain international markets. We currently provide the right to use such fiber and related assets to communications and internet service providers and third-party operators to support their telecommunications infrastructure.

•Property Interests. We own portfolios of property interests in Canada and the United States, including land under carrier or other third-party communications sites, which provide recurring cash flow under complementary leasing arrangements.

•Shared Generators and Power Solutions. We have contracts with certain of our tower tenants pursuant to which we provide access to shared backup power generators in the United States. In Africa, we also have contracts to power our

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tower tenants’ equipment through the use of shared infrastructure assets, primarily consisting of generators, solar panels and electricity storage solutions.

Services Operations

We offer tower-related services in the United States, including site application, zoning and permitting, structural and mount analyses, and construction management services, together with program management offerings that support customer deployment needs from project scoping through construction. Our services operations primarily support our site leasing business, including through the addition of new tenants and equipment on our sites. This segment accounted for 3%, 2% and 1% of our total revenue for the years ended December 31, 2025, 2024 and 2023, respectively.

Site Application, Zoning and Permitting. We engage in site application services on our own behalf in connection with our tower development projects, as well as on behalf of our tenants. We typically work with our tenants’ engineers to determine the geographic areas where new communications sites will best address the tenants’ needs and meet their coverage objectives. Once a new site is identified, we acquire the rights to the land or structure on which the site will be constructed, and we manage the permitting process to ensure all necessary approvals are obtained to construct and operate the communications site.

Structural and Mount Analyses. We offer structural and mount analyses services to wireless carriers in connection with the installation of their communications equipment on our towers. Our team of engineers can evaluate whether a tower structure can support the additional burden of the new equipment or if an upgrade is needed, and whether the proposed mount configurations will be capable of supporting the required loads in accordance with applicable standards. This enables our tenants to better assess potential sites before making an installation decision. Our structural and mount analyses capabilities enable us to provide higher quality service to our existing tenants by, among other things, reducing the time required to achieve on-air readiness, while also providing opportunities to offer structural and mount analyses services to third parties.

Construction Management. We offer construction management services to wireless carriers in connection with the deployment of their networks on our tower sites. Our construction management team oversees construction activities such as contractor sourcing, contractor selection and management, materials management, on-site quality control and closeout documentation for new installations or modifications. Our construction management capabilities enable us to provide efficient deployment to the carriers while ensuring that the construction work meets our quality control standards.

Strategy

Operational Strategy

As wireless communications technologies advance and the use of wireless services on handsets, tablets and other advanced mobile devices grows, there is a corresponding increase in demand for the communications infrastructure required to facilitate ever growing network demand. To capture this demand, our primary operational focus is to (i) increase the occupancy of our existing communications real estate portfolio to support global connectivity, (ii) invest in, and selectively grow, our communications real estate portfolio and service offerings, including through platform expansion initiatives, (iii) further improve our operational performance and efficiency and (iv) maintain a strong balance sheet. We believe these efforts to meet our customers’ needs will support and enhance our ability to capitalize on the growth in demand for wireless infrastructure. In addition, we expect to explore new opportunities to enhance or extend our shared communications infrastructure businesses, including those that may make our assets incrementally more attractive to new customers, or to existing customers for new uses, and those that increase our operational efficiency.

•Increase the occupancy of our existing communications real estate portfolio to support global connectivity. We believe that our highest incremental returns will be achieved by leasing additional space on our existing communications sites. Increasing demand for wireless services in our served markets has resulted in significant capital spending by major wireless carriers and other connectivity providers. As a result, we anticipate growing demand for our communications sites because they are attractively located and typically have capacity available for additional tenants and equipment. In the United States, incremental carrier network activity is being driven by ongoing 5G network deployments. In our international markets, carriers are increasingly deploying more advanced network technologies such as 4G and, in the case of our international markets with more mature network technology, 5G, while continuing to selectively augment legacy networks. We believe that the majority of our towers have capacity for additional tenants and that substantially all of our towers that are currently at or near full structural capacity can be upgraded or augmented to meet future tenant demand with relatively modest capital investment. Therefore, we will continue to target our sales and marketing activities to increase the utilization and return on investment of our existing communications sites.

•Invest in and selectively grow our communications real estate portfolio to meet our customers’ needs. We seek opportunities to invest in and grow our operations through our capital expenditure program, acquisitions and platform expansion initiatives. A significant portion of our inorganic growth has been focused on properties with lower initial

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tenancy because we believe that over time we can significantly increase tenancy levels, and therefore, drive strong returns on those assets. More recently, we have invested in strategic data center assets, including through our acquisition of CoreSite Realty Corporation (“CoreSite”) in late 2021 (the “CoreSite Acquisition”), which we believe can drive strong, recurring growth and also meaningfully enhance the value of our existing communications tower real estate through emerging edge compute opportunities in the future. We also expect to explore additional ways to use our platform expansion initiatives to enhance the efficiency of our operations over time.

•Further improve our operational performance and efficiency. We continue to seek opportunities to improve our operational performance throughout the organization. This includes investing in our systems and people as we strive to improve efficiency and provide superior service to our customers. To achieve this, we intend to continue to focus on customer service initiatives, such as reducing cycle times for key functions, including lease processing and tower structural analysis. We are also focused on developing and implementing power solutions across our footprint to help improve the overall efficiency of the communications infrastructure and wireless industries through our power as a service (PaaS) initiatives.

•Maintain a strong balance sheet. We remain committed to disciplined financial policies, which we believe result in our ability to maintain a strong balance sheet and will support our overall strategy and focus on asset growth and operational excellence. As a result of these policies, we currently have investment grade credit ratings. We continue to focus on maintaining a robust liquidity position and, as of December 31, 2025, had $11.1 billion of available liquidity. We believe that our investment grade credit ratings provide us consistent access to the capital markets and our liquidity provides us the ability to continue to invest in growing and augmenting our business.

Capital Allocation Strategy

The objective of our capital allocation strategy is to simultaneously increase adjusted funds from operations per share and our return on invested capital over the long term. To maintain our qualification for taxation as a REIT, we are required annually to distribute an amount equal to at least 90% of our REIT taxable income (determined before the deduction for distributed earnings and excluding any net capital gain) to our stockholders. After complying with our REIT distribution requirements, we plan to continue to allocate our available capital among investment alternatives that meet or exceed our return on investment criteria, while taking into account the repayment of debt consistent with our financial policies. On an ongoing basis, we also perform a comprehensive assessment of our global operations to ensure our portfolio is positioned to drive sustained growth and achieve our risk-adjusted return objectives. This assessment can influence our decisions on future capital allocation priorities between certain countries and assets, and may result in our decision to prioritize investments into developed markets, including the U.S. & Canada, Europe and the data centers markets. Conversely, this assessment can influence our decision to divest a portion, or all, of certain assets, including our Mexico fiber and Poland businesses in 2023, our Australia, India and New Zealand businesses in 2024 and our South Africa fiber business in 2025, and repurpose proceeds, and potential future capital, to other capital priorities, including investments into developed markets.

•Capital expenditure program. We expect to continue to invest in and expand our existing communications real estate portfolio through our capital expenditure program. This includes capital expenditures associated with site maintenance, increasing the capacity of our existing sites and projects such as new site and data center facility construction, land interest acquisitions and power solutions.

•Acquisitions. We intend to continue to pursue acquisitions of communications sites and other telecommunications infrastructure in our existing or new markets where we can meet or exceed our risk-adjusted return on investment criteria. The risk-adjusted hurdle rates used to evaluate acquisition opportunities consider additional factors such as the country and counterparties involved, investment and economic climate, legal and regulatory conditions and industry risk, among others.

•Return excess capital to stockholders. If we have excess capital available after funding (i) our required distributions, (ii) capital expenditures, (iii) the repayment of debt consistent with our financial policies and (iv) anticipated future investments, including acquisition and select platform expansion opportunities, we will seek to return such excess capital to stockholders, including through our stock repurchase programs.

International Strategy

Our international strategy incorporates portfolio analysis, capital prioritization and the disciplined management of overseas cash, including repatriation where feasible.

We believe that, in certain international markets, we can create value by expanding our existing, communications real estate leasing business, and leveraging our shared global experience, capabilities and services, to deliver a best-in-class offering for our customers and attractive risk-adjusted return for our shareholders. We strive to maintain a diversified approach to our

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international strategy by operating in a geographically diverse array of markets in a variety of stages of wireless network development.

Specifically as part of our ongoing portfolio analysis, we conduct an extensive review of a particular country’s historical and projected macroeconomic fundamentals, including inflation and foreign currency exchange rate trends, demographics, capital markets, tax regime and investment alternatives, and the general business, political and legal environments, including property rights and regulatory regime. We also analyze (i) the competitiveness of the country’s wireless market and (ii) how a particular market fits within our long-term strategic objectives.

Regulatory Matters

Towers, Antennas and Fiber. Our U.S. and international tower leasing businesses are subject to national, state and local regulatory requirements with respect to the registration, siting, construction, lighting, marking and maintenance of our towers. In the United States, the construction of new towers or modifications to existing towers may require pre-approval by the Federal Communications Commission (“FCC”) and the Federal Aviation Administration (“FAA”), depending on factors such as tower height and proximity to public airfields. Towers requiring pre-approval must be registered with the FCC and maintained in accordance with FAA standards. Similar requirements regarding pre-approval of the construction and modification of towers are imposed by regulators in other countries. Non-compliance with applicable tower-related requirements may lead to monetary penalties or site deconstruction orders.

Certain of our international operations are subject to regulatory requirements with respect to licensing, registration and permitting.

In Africa & APAC, our subsidiaries in Burkina Faso, Ghana, Kenya, Niger, Nigeria and Uganda are required to hold a license in order to establish and maintain passive telecommunications infrastructure services and DAS networks for communications service providers. Our subsidiaries in the Philippines and Bangladesh are required to hold a registration or license in order to establish, manage and operate passive telecommunications infrastructure services.

In Latin America, our subsidiary in Chile holds a concession of intermediate telecommunications services and our subsidiary in Argentina holds an information and communications technology service license. In Peru, our subsidiaries are registered as infrastructure providers. The subsidiary that holds our fiber business in Brazil is also licensed and regulated as an authorization holder to provide telecommunications services. In certain of the markets in which we operate, we are required to provide tower space to service providers on a non-discriminatory basis, subject to the negotiation of mutually agreeable terms. Additionally, one of our Brazilian subsidiaries, American Tower do Brasil – Cessao de Infraestruturas S.A. (“ATC Brazil”) issued non-convertible debentures in 2023 and in 2025, which are listed on the Brazilian stock exchange. Although the non-convertible debentures are held by another subsidiary of ours and are eliminated in consolidation, ATC Brazil is still subject to the listing requirements of such exchange.

Our international business operations may be subject to increased licensing fees or ownership restrictions. For example, in South Africa, the Broad-Based Black Economic Empowerment Act, 2003 (the “BBBEE Act”) has established a legislative framework for the promotion of economic empowerment of South African citizens disadvantaged by Apartheid. Accordingly, the BBBEE Act and related codes measure BBBEE Act compliance and good corporate practice by the inclusion of certain ownership, management control, employment equity and other metrics for companies that do business there. Our foreign operations may be affected if a country’s regulatory authority restricts, revokes or modifies spectrum licenses of certain wireless service providers or implements modifications or limitations on foreign ownership.

In all countries where we operate, we are subject to zoning restrictions and restrictive covenants imposed by local authorities or community organizations. While these regulations vary, they typically require tower owners or tenants to obtain approval from local authorities, environmental bodies or community standards organizations prior to tower construction or the addition of a new antenna to an existing tower. Local zoning authorities and community residents periodically oppose construction in their communities, which can delay or prevent new tower construction, new antenna installation or site upgrade projects, thereby limiting our ability to respond to tenant demand. This opposition and existing or new zoning, environmental or aviation regulations can increase costs associated with new tower construction, tower modifications or additions of new antennas to a site or site upgrades, as well as adversely affect the associated timing or cost of such projects. Further, additional regulations may be adopted that cause delays or result in additional costs to us or changes in the competitive landscape that may negatively affect our business. In addition, certain municipalities have sought to impose permit fees based upon structural or operational requirements of towers and certain regional and other governmental bodies have sought to impose levies or other forms of fees. These factors could materially and adversely affect our operations. In the United States, the Telecommunications Act of 1996 prohibits any action by state and local authorities that would discriminate between different providers of wireless services or ban altogether the construction, modification or placement of communications sites. It also prohibits state or local restrictions

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based on the environmental effects of radio frequency emissions to the extent the facilities comply with FCC regulations. Further, in February 2012, the United States government adopted regulations requiring that local and state governments approve modifications or colocations that qualify as eligible facilities under the regulations.

Portions of our business are subject to additional regulations, for example, in a number of states throughout the United States, certain of our subsidiaries hold Competitive Local Exchange Carrier (CLEC) or other status, in connection with the operation of our outdoor DAS networks business. In addition, we, or our customers, may be subject to new regulatory policies in certain jurisdictions from time to time that may materially and adversely affect our business or the demand for our communications sites.

Data Centers. Our U.S. data center facilities and related assets are subject to various federal, state and local regulations, such as state and local fire and life safety regulations and Americans with Disabilities Act (“ADA”) federal requirements. If one of our properties is not in compliance with these regulations, we may be required to make significant unanticipated expenditures in order to comply with such regulations and/or pay fines or civil damage awards. Existing regulations may subsequently change or future regulations may be enacted, either of which could have a similar impact as described above, and could materially and adversely affect our operations.

In some markets, our data centers are subject to zoning restrictions imposed by local authorities. While these regulations vary, they may require data center operators to obtain approval from local authorities or environmental bodies prior to data center construction or modification of an existing facility. Local authorities and community residents periodically oppose construction in their communities, which can delay or prevent new data center construction, thereby limiting our ability to respond to tenant demand. This opposition and existing or new zoning or environmental regulations can increase costs associated with new data center construction or modifications to existing facilities, as well as adversely affect the associated timing or cost of such projects.

Environmental Matters. Our U.S. and international operations are subject to various national, state and local environmental 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, the siting of our towers and the maintenance of our data center facilities. We may be required to obtain permits, pay additional property taxes, comply with regulatory requirements and make certain informational filings related to hazardous substances or devices used to provide power such as batteries, generators and fuel at our tower sites and/or data center facilities. When a site is decommissioned, we are required to follow applicable regulatory requirements, including by following decommissioning procedures and environmental management plans. With respect to our data center facilities, the presence of contamination, asbestos, lead or lead-based paint, mold or other air quality issues or the failure to remediate contamination, asbestos, lead or lead-based paint, mold or other air quality issues at our facilities may expose us to third-party liability or materially and adversely affect our ability to sell, lease or develop the real estate or to borrow using the real estate as collateral. Violations of these types of regulations could subject us to fines or criminal sanctions.

Additionally, in the United States and in other countries where we operate, before constructing a new tower or adding an antenna to an existing site, we must review and evaluate the impact of the action to determine whether it may significantly affect the environment and whether we must disclose any significant impacts in an environmental assessment. If a tower or new antenna might have a material adverse impact on the environment, FCC or other governmental approval of the tower or antenna could be significantly delayed or modifications to the site construction plans may be necessary.

The U.S. Environmental Protection Agency, or EPA, some of the states and localities in which we operate and the governments of other countries in which we operate have also enacted or proposed certain climate-related disclosures and may adopt new regulations related to the use of fossil fuels or requiring the use of alternative fuel or renewable energy sources to power energy resources that serve our data centers. Efforts to support and enhance renewable electricity generation may increase our costs of electricity above those that would be incurred through procurement of conventionally generated electricity. Our data centers require and consume significant amounts of power, including electricity generated by the burning of fossil fuels. These laws, regulations and stakeholder requests could limit our ability to develop new facilities or result in substantial compliance, maintenance, repair, retrofit and construction costs, including capital expenditures for environmental control facilities and other new equipment. Changes in regulations that affect electric power providers, such as regulations related to the control of greenhouse gas emissions or other climate change-related matters, could adversely affect the costs of electric power and increase our operating costs, which could adversely affect our business, financial condition and results of operations or those of our customers. See “Risk Factors” in Item 1A of this Annual Report for more information on our data center-related risks.

Health and Safety. In the United States and in other countries where we operate, we are subject to various national, state and local laws regarding employee health and safety, including protection from radio frequency exposure and air quality issues.

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Competition

Our industry is highly competitive. There are frequently new market participants that create additional competition. We compete, both for new business and for the acquisition of assets, with other public tower companies, such as Crown Castle International Corp., SBA Communications Corporation, Vertical Bridge, Telesites S.A.B. de C.V. and Cellnex Telecom, S.A., wireless carrier tower consortia and private tower companies, private equity sponsored firms, carrier-affiliated tower companies, independent wireless carriers, tower owners, broadcasters and owners of non-communications sites, including rooftops, utility towers, water towers and other alternative structures. Our data center business also competes with a variety of companies offering similar data center solutions and services, including space, power, interconnection and development services. We believe that location and capacity, grid distribution constraints, network and/or interconnection density, price, quality and speed of service have been, and will continue to be, significant competitive factors affecting owners, operators and managers of communications sites and data center facilities.

Our services business competes with a variety of companies offering individual, or combinations of, competing services. The field of competitors includes site application consultants, zoning consultants, real estate firms, right-of-way consultants, structural engineering firms, construction management firms, tower owners/managers, telecommunications equipment vendors who can provide turnkey site development services through multiple subcontractors and our tenants’ personnel. We believe that our tenants base their decisions for services on various criteria, including a company’s experience, local reputation, price and time for completion of a project.

For more information on demand trends in our industry, see Item 7 of this Annual Report under the caption “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Executive Overview.”

Human Capital Resources

As of December 31, 2025, we employed 4,866 full-time individuals, including 2,388 employees based in the United States and 2,478 employees based internationally. Our teams in our more than 20 countries around the world are our most important assets and fundamental to our success. Aligned with our business strategy, our human capital management strategy focuses on developing and delivering solutions to attract, develop, engage and retain top talent in each of the countries where we operate. Our Chief Human Resources Officer regularly reports to the Compensation and Human Capital Committee of our Board of Directors (our “Board”) on our initiatives related to human capital management.

A critical factor in our success is ensuring that an inclusive and collaborative workplace remains at the core of our business culture, infusing fresh ideas, helping us remain connected to our customers in a dynamic global market and ensuring mutual respect guides us in our interactions both internally and externally. Additionally, we have implemented several initiatives designed to support our inclusion efforts, including pledges from the American Tower Foundation. We also enable global employee resource groups to promote better employee engagement, which are open to all employees with the goal of enhancing professional development, connection and collaboration for everyone.

As a critical investment in our capacity to provide our customers with outstanding support and customer service, we offer a variety of development opportunities unique to each market to cultivate our talent throughout our global organization. For individual contributors, we provide resources in up to five languages that focus on job-specific training and general topics, such as productivity, collaboration and project management. We create and customize courses to meet regional needs and update these courses regularly to address changing marketplace dynamics and employee interests.

Developing our managers is critical to our success, and several resources and tools are provided to all levels of management. For example, our Management Essentials program provides continuous learning opportunities through training led by American Tower leaders globally. Managers learn tools and best practices that enable both management and team success, and that build and strengthen competencies to better respond to the needs of a growing and increasingly complex organization. Furthermore, our Gateway to Leadership program builds further on the skills and competencies we deliver through Management Essentials by providing additional leadership training for managers in Europe, Africa and Latin America. Our annual Accelerated Leadership Development program, in collaboration with the INSEAD executive education program, provides our next generation leaders in Latin America, Europe, the U.S. and Africa, with a seven-week intensive workshop to enhance management and leadership skills. For our employees with high potential, we offer several professional development opportunities designed to support these employees through a career path journey to become inclusive leaders. These are all supported by a comprehensive talent-management review process to develop future leaders and ensure effective succession planning. Additionally, our virtual corporate university, ATC YOU, provides our employees with a range of global learning resources for professional development and career growth.

Our recruiting efforts consistently include strategies to build qualified candidate pipelines with varied skills and backgrounds and promote a culture that supports a diverse team of global employees. We have developed education initiatives and increased access to professional development opportunities for employees, including an enhanced focus on mentoring opportunities.

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Our Compensation and Human Capital Committee also approved a shared human capital management goal for the entire executive team for 2025, which focuses on developing talent.

We are committed to the safety of our employees and surrounding communities. Depending on the role, team members are required to pass and complete regular safety training courses and follow specific tower and site safety protocols with the support of operational manuals. A key component of our culture is a strong commitment to incident reporting and corrective actions, as well as a comprehensive program for ensuring vendor compliance with safety standards and certifications. Our strict adherence to the rigorous standards set forth by the relevant government agencies and other authorities, such as the Telecommunications Infrastructure Registered Apprenticeship Program and Telecommunications Industry Association, is critical to ensuring our towers are structurally safe for field personnel, vendors, customers and communities. We have several employee security protocols and standards in place to better protect our people and assets worldwide. These include global standards for the security of international travelers and personnel ground movements. We also operate a traveler assistance program that allows us to better monitor international travel and provide employees with relevant trip advice and 24/7 assistance services. A related journey risk management program provides support for trips in complex threat environments, and includes hostile environment awareness training, real-time tracking of personnel and 24/7 support. Furthermore, as part of our efforts to globalize our operations, we created a new global Health & Safety (“H&S”) function tasked with strengthening our H&S policies and culture, ensuring compliance with global and local regulations and fostering a proactive safety-first mindset across all organizational levels.

We offer medical and parental leave benefits to full-time employees across all markets, with some local variation. We conduct wellness check-ins and offer resources to support our employees’ mental health and well-being, including access to a free Employee Assistance Program, which offers confidential assistance on a wide range of issues. We also offer market competitive benefits in all locations and, in 2025, continued our behavioral health benefit in the United States to support employees’ mental well-being.

Executive Officers

For information about our Executive Officers, see Item 10 of this Annual Report under the caption “Directors, Executive Officers and Corporate Governance.”

Available Information

Our internet website address is www.americantower.com. Information contained on our website is not incorporated by reference into this Annual Report, and you should not consider information contained on our website as part of this Annual Report. You may access, free of charge, our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, plus amendments to such reports as filed or furnished pursuant to Sections 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (“Exchange Act”), through the “Investor Relations” portion of our website as soon as reasonably practicable after we electronically file such material with, or furnish it to, the Securities and Exchange Commission (the “SEC”).

We have adopted a written Code of Ethics and Business Conduct Policy (the “Code of Conduct”) that applies to all of our employees and directors, including, but not limited to, our principal executive officer, principal financial officer and principal accounting officer or controller or persons performing similar functions. The Code of Conduct, our Corporate Governance Guidelines and the charters of the audit, compensation and nominating and corporate governance committees of our Board are available on the “Investor Relations” portion of our website, under the “Corporate Governance” tab. In the event we amend the Code of Conduct, or provide any waivers of the Code of Conduct to our directors or executive officers, we will disclose these events on our website as required by the regulations of the New York Stock Exchange (the “NYSE”) and applicable law.

In addition, paper copies of these documents may be obtained free of charge by writing us at the following address: 222 Berkeley Street, Boston, Massachusetts 02116, Attention: Investor Relations; or by calling us at (617) 375-7500.