Executive Pay Structure

OVERVIEW

ANNUAL BASE SALARY

American Tower provides a competitive level of compensation to its executive officers to attract and retain highly-qualified executive talent and reward sustained performance over time. The base salary is determined on an annual basis.

ANNUAL PERFORMANCE INCENTIVE PROGRAM

American Tower provides at-risk, variable cash pay opportunity for performance over one year to motivate its executive officers to achieve or exceed annual goals within appropriate risk parameters.

Target annual performance incentive awards for the CEO:

Target annual performance incentive awards for the other NEOs:

tied to achievement of the pre-established Company financial goals

tied to achievement of the pre-established Company financial goals

tied to achievement of pre-established individual performance goals

LONG-TERM INCENTIVE (LTI) PLAN

American Tower provides long-term equity-based pay opportunity for sustained operating performance to focus its executives on the creation of long-term stockholder value.

Target grant date award for the CEO:

Target grant date for the other NEOs:

allocated to performance-based restricted stock units (PSUs)

allocated to PSUs

allocated time-based restricted stock units (RSUs)

allocated to RSUs

The number of PSUs earned is based on achievement of pre-established performance goals for a three-year performance period: 70% based on cumulative Consolidated AFFO per Share(1) 30% based on average ROIC(1) The actual payout is based on performance levels against these goals.

Each RSU grant vests 25% annually over four years, commencing one year from the date of grant. See “Compensation Discussion and Analysis” beginning on page 30.

⁽¹⁾Definitions of non-GAAP financial measures and reconciliations to GAAP can be found in Appendix A.

(1)Mr. Bartlett was appointed President and CEO on March 16, 2020 (2)As of December 31, 2019 †Sole Management Director Nominee *Lead Director

Member

Chair

Audit Committee Financial Expert

Director Nominee Snapshot

Board Diversity

While we do not have a specific diversity policy for our Board of Directors (Board), our Corporate Governance Guidelines provide for selecting Directors who reflect a diverse set of skills, professional and personal backgrounds, perspectives and experiences. We are proud to have Directors who are highly diverse, including with respect to gender, ethnicity and experience.

Our Board consists of individuals with diverse and complementary business, leadership and financial expertise. Many of our Directors have leadership experience at major U.S. and multinational companies, as well as experience on the boards of other companies and organizations, which provide an understanding of different business processes, challenges and strategies. In addition, many of our Directors have industry and public policy experience that provides insight into issues faced by public companies.

Our Amended and Restated By-Laws (By-Laws) permit a group of up to 20 stockholders who have owned at least three percent (3%) of American Tower stock continuously for at least three (3) years the ability to submit Director nominees—up to twenty-five percent (25%) of the Board—for inclusion in our proxy statement if the stockholder(s) and the nominee(s) satisfy the requirements specified in our By-Laws.

PROXY ACCESS

Holders of at least 3% of AMT stock held by up to 20 stockholders

Holding the stock continuously for at least 3 years

Can nominate up to 25% of the Board for election at an annual meeting of stockholders

In addition, we provide our stockholders with the right to call a special meeting and act by written consent, the terms of

which reflect the mainstream of current market practice.

Related Party Transactions, Director Independence and Code of Conduct

For fiscal year 2019, there were:

•NO related party transactions

•NO transactions that affected our Directors’ independence

•NO violations or waivers of our Code of Conduct with respect to our Directors or executive officers

Corporate Governance

General

Our Board is committed to strong corporate governance practices and dedicated to ensuring that American Tower is managed for the long-term benefit of our stockholders and other stakeholders. To fulfill this role, the Board and its three standing committees—Audit; Compensation; and Nominating and Corporate Governance (Nominating)—meet throughout the year and engage in meaningful discussions with management to ensure that the Board is informed regarding the Company’s activities, operating plans and strategic initiatives.

To promote full compliance with all applicable corporate governance standards and remain aligned with best practices, the Board has adopted corporate governance principles and procedures, which it reviews and amends as necessary. We also continuously review guidance and interpretations provided by the Securities and Exchange Commission (SEC) and the New York Stock Exchange (NYSE). Furthermore, we engage in meaningful discussions with our stockholders regarding governance issues and potential improvements.

You can access the charters for each of our current committees, our Corporate Governance Guidelines, and By-Laws on the “Investor Relations – Corporate Governance” section of our website, www.americantower.com, and our Code of Conduct in the “Corporate Responsibility – Ethics” section of our website. You may also request such documents to be mailed to you by writing to: American Tower Corporation, 116 Huntington Avenue, Boston, Massachusetts 02116, Attention: Investor Relations. Each committee charter, our Corporate Governance Guidelines and our Code of Conduct are reviewed annually.

Board of Directors

Our Board is committed to highly effective corporate governance that is responsive to stockholders, ensuring that the Company delivers on its strategic objectives.

BOARD LEADERSHIP STRUCTURE

The Board is led by our independent Lead Director, Pam Reeve, a role she has held since May 2004 when appointed by the independent Directors. All Directors, other than the CEO, are independent and all members of the three standing committees are independent. Following the 2020 Annual Meeting of Stockholders, Pam Reeve will serve as non-executive Chair of the Board, subject to her re-election as a Director.

The Nominating Committee regularly reviews the current Board structure. Consistent with our Corporate Governance Guidelines, the Lead Director performs the following responsibilities to manage the Board effectively while providing independent oversight:

•Assisting executive management on communications with Directors regarding strategic, business, financial and governance matters;

•Communicating with and assigning tasks to the other Board members;

•After obtaining input from the other independent Directors, approving agendas, materials and schedules for upcoming Board meetings and reviewing meeting schedules to ensure that there is sufficient time for discussion of all agenda items;

•Together with the Chairman of the Compensation Committee, preparing and conducting the annual performance review of the CEO, based on input from each Director on the CEO’s performance and achievements during the year; and

•Serving as Chairperson of all Board meetings, including the Board’s executive sessions of independent Directors, which are held at least once per quarter.

Other duties include:

•Engaging in consultation and direct communication with major stockholders, including responding to inquiries, as appropriate;

•Assuring that a succession plan is in place for the CEO;

•Meeting with the CEO frequently to discuss strategy and meeting regularly with senior management other than the CEO;

•Serving as liaison for, and facilitating a working relationship between, the independent Directors and the CEO;

•Soliciting direct feedback from independent Directors;

•Calling meetings of the independent Directors at any time, as necessary;

•Leading discussions regarding risk management;

•Participating in the interview process for prospective Directors;

•Ensuring timely and appropriate information flow to the Board; and

•Performing such other duties as the Board may from time to time designate.

SELECTION OF DIRECTORS AND BOARD REFRESHMENT

In order to maintain sustained growth of the Company, it is important we continue to have a Board with the requisite competencies to provide sound stewardship. We are committed to ensuring that our Board is composed of Directors who bring a wealth of leadership experience, diverse viewpoints, knowledge and skills that benefit our Company and stockholders. The Nominating Committee reviews the characteristics, skills, background and experience of the Board as a whole and its individual members on an ongoing basis to assess those traits against the needs identified to benefit the Company, its management and its stockholders.

Our Board consists of Directors with a range of tenure, with our longer-serving Directors providing important institutional knowledge and experience and our newer Directors bringing fresh perspectives to deliberations. The Board, including the Nominating Committee, believes that periodic Board refreshment is necessary to optimize the Board’s effectiveness. In September 2019, the Board appointed Lockheed Martin's former Chief Financial Officer, Bruce Tanner, to complement the composition and skill sets of our Board. As we expand our operations throughout the world, the Nominating Committee continues to strive to maintain a Board with the knowledge and skills necessary to oversee a global company effectively.

Board Succession Planning

The Nominating Committee works with the Lead Director to develop a Board succession plan that effectively promotes the Company’s long-term strategic objectives. The Nominating Committee continuously evaluates the Board’s composition in light of the Company’s strategy and regularly reviews the current tenure of the Board. The Nominating Committee selects Directors who will prove to be strategic assets capable of assessing and addressing risks, trends and opportunities for the Company in the future.

Process for Director Selection/Nomination

On a quarterly basis, the Nominating Committee reviews the size and composition of the Board using a rigorous matrix of identified skills, experience and other criteria relevant to a global, publicly traded company in the mobile telecommunications infrastructure industry. As described in our Corporate Governance Guidelines, the Nominating Committee assesses director candidates based on specific criteria as outlined under the section “Director Skills and Qualifications Criteria” on page 15 below. Although the Nominating Committee does not assign specific numeric weights to these skills in its assessments, any Director candidate is expected to possess substantive knowledge or experience in several of the areas specified in the criteria. In addition, our Board believes it is important to review its effectiveness and that of its standing committees on an annual basis and, accordingly, engages with an outside independent consultant to conduct that evaluation and provide critical feedback. The feedback generated from this process assists the Board, and particularly the Nominating Committee, in determining the composition and skill set required for our Board to function effectively and oversee management’s implementation of the Company’s strategic goals and priorities.

In considering candidates for inclusion in the Board’s slate of recommended Director nominees, the Nominating Committee recommends individuals whom it believes can best enhance the success of the business and represent stockholder interests through the exercise of sound judgment in light of the full Board’s experience. The Nominating Committee considers diversity to be a key criterion in searching for new director candidates. To identify and evaluate Director candidates, the Nominating Committee requests recommendations from Board members and others, reviews and discusses biographical information and background material relating to potential candidates and, along with other Board members, interviews selected potential candidates. The Nominating Committee may then choose to present such candidates to the Board for consideration.

Upon selection of a candidate, the individual is interviewed by members of the Board and an analysis is prepared to further assess the suitability of the candidate to address the needs of the Board. If the candidate is selected for recommendation to the Board, a review of his or her independence and potential conflicts is conducted.

As a stockholder, you may recommend to the Nominating Committee an individual for consideration as a potential Director candidate. To do so, please submit the candidate’s name, together with appropriate biographical information and background materials, to: David E. Sharbutt, Chairperson of the Nominating and Corporate Governance Committee, c/o General Counsel, American Tower Corporation, 116 Huntington Avenue, Boston, Massachusetts 02116. If the biographical and background material provided for a stockholder recommended candidate is appropriate, the Nominating Committee will evaluate the candidate by following substantially the same process, and applying substantially the same criteria, as for candidates submitted by Board members. The Nominating Committee will review each candidate’s qualifications in light of the Board’s needs, given the current mix of Director attributes.

Stockholders proposing Director nominations must comply with the advance notice and specific information requirements in our By-Laws, which include, among other things, the disclosure of hedging, derivative interests and other material interests of the nominating stockholder and Director nominee. In addition, each Director nominee proposed by a stockholder must deliver, promptly following the stockholder meeting at which such nominee is elected or re-elected, a statement that he or she agrees to tender an irrevocable advance resignation in accordance with our Corporate Governance Guidelines.

DIRECTOR SKILLS AND QUALIFICATIONS CRITERIA

As demonstrated in the Directors’ biographies beginning on page 64 and the “Board Diversity” section in the Proxy Statement Summary on page 9, the Nominating Committee focuses not only on traditional diversity categories such as gender, race and national origin but also diversity in experience and skills. The Nominating Committee actively seeks out qualified women, persons of color and other individuals from minority groups to include in the pool from which new candidates are selected. The Nominating Committee incorporates this broad view of diversity into its nomination process and seeks to maintain a Board that is strong in its collective knowledge and has a diversity of skills, ability, perspectives and experience. The Nominating Committee evaluates each individual Director candidate in the context of the Board as a whole, based on the following criteria:

BOARD MEETINGS

During fiscal year 2019, our Board held four regular meetings in person and three special meetings by telephone. Each current Director attended at least 75% of the aggregate number of meetings of our Board and the committees on which he or she served. Mr. Tanner was appointed to the Board in September 2019 and therefore

he did not serve on the Board for the entire calendar year. However, Mr. Tanner attended all Board meetings in 2019 after his appointment as Director and he was not a member of any committee at the time that the meetings were held. All of our Directors as of the date of our 2019 Annual Meeting of Stockholders attended the meeting. We encourage, but do not require, our Directors to attend each annual meeting of stockholders.

In determining whether to recommend a Director for re-election, the Nominating Committee also considers the Director’s past attendance at meetings and participation in, and contributions to, the activities of the Board and standing committees.

DIRECTOR ONBOARDING AND CONTINUING EDUCATION

To familiarize new Directors with American Tower’s business, strategies and policies, and to assist new Directors in developing Company and industry knowledge to optimize their service on the Board, we conduct a robust orientation program for new Directors, which includes, among other things, a presentation on our business and wireless infrastructure sector, each of our regional markets, our capital structure, board and committee responsibilities, corporate responsibility (including the American Tower Foundation), legal and risk management, corporate governance guidelines and policies and securities trading and reporting. Because we believe that our Directors should be continually educated regarding corporate governance processes and practices, our business and our industry, we periodically conduct Board education sessions, often using external experts. The Nominating Committee annually reviews that year’s Director training initiatives to determine programs for the upcoming year. Additionally, we encourage each independent Director to attend, annually and at the Company’s expense, at least one board education course offered by either an academic institution or a professional service organization.

DIRECTOR INDEPENDENCE

The NYSE rules effectively create a two-step process for determining whether a Director qualifies as “independent.” First, a Director must satisfy the bright-line standards for independence established by the NYSE. Second, the Board must affirmatively determine that the Director has no material relationship with the Company, either directly or as a partner, stockholder or officer of an organization that has a relationship with the Company.

As set forth in our Corporate Governance Guidelines, the Board has established guidelines to help it determine whether a Director has a material relationship with the Company. Under these guidelines, a Director is not considered to have a material relationship with the Company solely on the grounds that he or she:

•is an executive officer or employee, or has an immediate family member who is an executive officer, of a company that makes payments to, or receives payments from, us for property or services, unless the amount of such payments or receipts, in any of the three fiscal years preceding the determination, exceeded the greater of $1 million or two percent (2%) of such other company’s consolidated gross revenues;

•is an executive officer of another company that is indebted to us, or to which we are indebted, unless the total amount of either company’s indebtedness to the other is more than five percent (5%) of the total consolidated assets of the company at which he or she serves as an executive officer;

•is a director of another company that does business with us, provided that he or she owns less than five percent (5%) of the outstanding capital stock of the other company and recuses himself or herself from any deliberations of our Board with respect to such other company; or

•serves as an executive officer of any charitable organization, unless our charitable contributions to the organization, in any of the three fiscal years preceding the determination, exceeded the greater of $1 million or two percent (2%) of such charitable organization’s consolidated gross revenues.

In addition, ownership of a significant amount of our Common Stock, by itself, does not constitute a material relationship.

For relationships not covered by these guidelines, the other independent Directors will determine whether a material relationship exists, based upon the recommendation of the Nominating Committee. No immediate family relationship exists between any of our Directors or executive officers and any other Directors or executive officers.

The Board has determined that, based on his or her compliance with the Board’s established guidelines, each of American Tower’s non-management Directors has no material relationship with us and is “independent” under Section 303A.02 of the NYSE listing standards. In making its assessment, the Board determined that each of Messrs. Dolan, Hormats, Lara and Tanner and Ms. Reed had no relationship with the Company, other than being a Director or stockholder. With respect to Messrs. Macnab, Sharbutt and Thompson and Mses. Lieblein and Reeve, the Board determined that relationships that existed with the Company were immaterial.

Specifically, the Board considered that each of Messrs. Macnab, Sharbutt and Thompson and Mses. Lieblein and Reeve served or currently serves as a director (or executive officer in the case of Mr. Macnab) of a company that does business with us, as follows: Mr. Macnab served as a director and executive officer of National Retail Properties, Inc. until April 2017; Mr. Sharbutt currently serves as a director of Flat Wireless, LLC; Mr. Thompson currently serves as a director of Spok Holdings, Inc.; Ms. Lieblein currently serves as a director of Southwest Airlines Co. and Honeywell International, Inc.; and Ms. Reeve currently serves as a director and chair of Frontier Communications Corporation. In each case, the Board determined that such service was in accordance with the NYSE listing standards and our Corporate Governance Guidelines in that none of these Directors beneficially owns five percent (5%) or more of the outstanding capital stock of the applicable company, each recuses himself or herself from any deliberations of the Board with respect to the applicable company and, in each case, payments made to or received from each applicable company were less than $1 million or two percent (2%) of both the Company’s or the applicable company’s revenue in fiscal year 2019.

Each member of the Audit Committee is an audit committee financial expert under SEC rules and has the accounting or related financial-management expertise required under NYSE rules. In addition, each member is “independent” under the additional independence requirements of Rule 10A-3 under the Securities Exchange Act of 1934, as amended (Exchange Act). No Audit Committee member serves on the audit committee of more than two other public companies.

For more information on the Compensation Committee’s role and our processes and procedures for determining executive compensation, see “Compensation Discussion and Analysis” beginning on page 30.

Nominating and Corporate Governance Committee

Members: David E. Sharbutt (Chair) Robert D. Hormats Pamela D.A. Reeve Samme L. Thompson

Key Responsibilities:

•Identifies and recommends individuals to serve on the Board and its committees. •Develops and makes recommendations with respect to our Corporate Governance Guidelines, including the appropriate size, composition and responsibilities of the Board and its committees. •Reviews corporate governance best practices and market trends. •Reviews and approves or ratifies any related party transactions. •Reviews any contemplated outside directorships of current Board members. •Establishes performance criteria for the annual evaluation of the Board and its committees, and oversees the annual self-evaluation by Board members. •Responds to stockholder requests and inquiries. •Reviews and recommends Director training initiatives, and reviews Director onboarding program. •Oversees sustainability reports. •Advises the Board with respect to Board committee charters, composition and protocol, including the current Board structure.

Meetings in 2019: 4

ANNUAL EVALUATION

To identify areas that are effective and areas for improvement, our Board, with oversight by the Nominating Committee, conducts annual evaluations of its performance and that of each of its three standing committees. The Board recognizes that a robust and constructive evaluation process is essential to good governance and effectiveness. The table below summarizes the process followed in 2019. We expect to conduct a similar Board and committee self-evaluation process in 2020.

			Identification of Third-Party Consultant: Information Gathering The Nominating Committee hired an independent consultant to conduct the Director self-evaluation process. The consultant used a variety of evaluation formats, including: •interviews and discussion sessions with individual Directors, standing committees, the full Board and members of senior management who interact with the Board; •surveys of each Board member to facilitate an objective, independent assessment of the effectiveness of the Board and applicable committees; and •meetings of the Board and each committee to assess the Board and committee performance firsthand. This process was intended to encourage candid feedback from Directors regarding the actions of the Board and the standing committees. Information gathered included Board and committee effectiveness and performance, agenda topics, materials, tenure, skills, leadership and strategy. Board members were also invited to discuss the performance of the Lead Director.
			Review and Assessment: Report to Nominating Committee and Board The independent consultant: •aggregated the results of its observations, interviews, feedback and surveys regarding Director performance, Board dynamics and effectiveness of the Board and the committees; and •presented the findings to our Nominating Committee and full Board. The data identified any themes or issues that had emerged and included suggestions for areas of improvements for each committee and the Board and an action plan for implementation of the changes suggested. The full Board reviewed the results of the consultant’s assessment and each committee reviewed its results.
			Action by the Nominating Committee The Nominating Committee: •used these results to review and assess the Board’s and each committee’s composition and required skill sets, responsibilities, structure, processes and effectiveness; and •assessed the responsive actions to be taken to address areas of improvement in the performance of the Board and each of the committees. This included succession planning and an assessment as to the need for specific skills, experience and perspectives which would benefit the Board in the future. The findings were compared against the strategic objectives of the Company and the skills matrix in order to address future needs of the business.