[Form 4] AMERICAN TOWER CORP /MA/ Insider Trading Activity

Rhea-AI Filing Summary

Ruth T. Dowling, Executive Vice President, Chief Administrative Officer, General Counsel and Secretary of American Tower Corp (AMT), reported a sale of 55 shares of Common Stock on 10/01/2025 at a price of $193.32 per share. The filing explains the 55 shares were delivered to the issuer to satisfy withholding taxes related to the vesting of restricted stock units previously granted under the company’s 2007 Equity Incentive Plan. After the transaction the reporting person beneficially owns 21,262 shares, which includes 35 shares acquired under the issuer’s employee stock purchase plan in May 2025.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

Dowling Ruth T

(Last) (First) (Middle)

116 HUNTINGTON AVENUE

(Street)

BOSTON MA 02116

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
AMERICAN TOWER CORP /MA/ [ AMT ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP, Chief Admin Ofr, GC & Sec

3. Date of Earliest Transaction (Month/Day/Year)
10/01/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	10/01/2025		F(1)		55	D	$193.32	21,262(2)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. 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.

2. Includes 35 shares acquired under the issuer's employee stock purchase plan in May 2025.

Remarks:

	/s/ Marina A. Breed, as attorney-in-fact	10/03/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did AMT reporting person Ruth T. Dowling disclose?

The filing reports a sale of 55 shares of AMT common stock on 10/01/2025 at $193.32 per share to cover withholding taxes on vested restricted stock units.

How many AMT shares does the reporting person beneficially own after the transaction?

The filing states the reporting person beneficially owns 21,262 shares following the reported transaction.

Why were the 55 shares sold according to the Form 4?

The Form 4 explains the 55 shares were delivered to the issuer for payment of withholding taxes in connection with vesting of restricted stock units under the 2007 Equity Incentive Plan.

Does the filing include any shares acquired through an employee program?

Yes; the filing notes inclusion of 35 shares acquired under the issuer’s employee stock purchase plan in May 2025.

Who signed the Form 4 filing on behalf of the reporting person?

The Form 4 is signed by Marina A. Breed, as attorney-in-fact, with a signature date of 10/03/2025.