AMT · American Tower Corp /Ma/

Includes 142 shares acquired under the issuer's employee stock purchase plan in May 2026.

The sale reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 29, 2025.

The sale reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 29, 2025.

Includes 41 shares acquired under the issuer's employee stock purchase plan in May 2026.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of restricted stock units previously granted under the 2007 Equity Incentive Plan, as amended.

Shares gifted to a charitable organization.

The sale reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 29, 2025.

The sale reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 29, 2025.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended (the "Plan"), and vest 1/3rd annually over three years, commencing one year from the date of grant. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended (the "Plan"), and vest 1/3rd annually over three years, commencing one year from the date of grant. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended (the "Plan"), and vest 1/3rd annually over three years, commencing one year from the date of grant. Each RSU represents a contingent right to receive one share of Common Stock.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs and performance-based restricted stock units previously granted under the Plan.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs and performance-based restricted stock units previously granted under the Plan.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended (the "Plan"), and vest 1/3rd annually over three years, commencing one year from the date of grant. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended (the "Plan"), and vest 1/3rd annually over three years, commencing one year from the date of grant. Each RSU represents a contingent right to receive one share of Common Stock.

Includes 80 and 40 shares acquired under the issuer's employee stock purchase plan in May 2025 and November 2025, respectively.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs and performance-based restricted stock units previously granted under the Plan.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended (the "Plan"), and vest 1/3rd annually over three years, commencing one year from the date of grant. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

Shares delivered to the issuer for the payment of withholding taxes in connection with the vesting of RSUs previously granted under the Plan.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended (the "Plan"), and vest 1/3rd annually over three years, commencing one year from the date of grant. Each RSU represents a contingent right to receive one share of Common Stock.

These restricted stock units ("RSUs") were granted pursuant to the 2007 Equity Incentive Plan, as amended, and vest on March 10, 2027. Each RSU represents a contingent right to receive one share of Common Stock.

This option was granted pursuant to the 2007 Equity Incentive Plan, as amended, and is exercisable in 25% cumulative annual increments beginning March 10, 2017.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 6, 2025.

Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $189.58 to $190.09 per share.

The sale reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 29, 2025.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 6, 2025.

Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $187.31 to $188.30 per share.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 6, 2025.

Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $188.31 to $189.30 per share.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 26, 2025.

Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $188.82 to $189.78 per share.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 26, 2025.

Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $189.92 to $190.88 per share.

This option was granted pursuant to the 2007 Equity Incentive Plan, as amended, and is exercisable in 25% cumulative annual increments beginning March 10, 2017.