(AMT)

Role: EVP, CFO & Treasurer
Signature: /s/ Marina A. Breed, as attorney-in-fact
Issuer symbol: AMT
Transactions as of: 13 Feb 2025
Net transactions value: -$1,576,182
Form type: 4
Filing time: 18 Feb 2025, 16:05:35 UTC
Previous filing: 17 Jan 2025
Next filing: 03 Mar 2025
SEC: View on sec.gov

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	AMT	Common Stock	Options Exercise	$1,566,836	+16,568	+26%	$94.57	79,360	13 Feb 2025	Direct
transaction	AMT	Common Stock	Sale	$2,854,272	-15,051	-19%	$189.64	64,309	13 Feb 2025	Direct	F1, F2
transaction	AMT	Common Stock	Sale	$288,746	-1,517	-2.4%	$190.34	62,792	13 Feb 2025	Direct	F1, F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	AMT	Option to Purchase Common Stock	Options Exercise	$0	-16,568	-100%	$0.000000	0	13 Feb 2025	Common Stock	16,568	$94.57	Direct	F4

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.

Transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c).

Explanation of Responses:

Id	Content
F1	The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 13, 2024.
F2	Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $189.14 to $190.08 per share.
F3	Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $190.23 to $190.44 per share.
F4	This option was granted pursuant to the 2007 Equity Incentive Plan, as amended, and is exercisable in 25% cumulative annual increments beginning March 10, 2016.