AMERICAN TOWER CORP /MA/ — Director's Dealing 2016

May 4, 2016

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AMERICAN TOWER CORP /MA/ (AMT)
CIK: 0001053507
Period of Report: 2016-05-02

Reporting Person: Bartlett Thomas A (EVP and CFO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2016-05-02	Common Stock	M	38860	$76.90	Acquired	135289	Direct
2016-05-02	Common Stock	M	53909	$81.18	Acquired	189198	Direct
2016-05-02	Common Stock	S	91759	$105.03	Disposed	97439	Direct
2016-05-02	Common Stock	S	1010	$105.54	Disposed	96429	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2016-05-02	Option to Purchase Common Stock	$76.90	M	38860	Disposed	2023-03-11	Common Stock (38860)	Direct
2016-05-02	Option to Purchase Common Stock	$81.18	M	53909	Disposed	2024-03-10	Common Stock (53909)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	193	Indirect

Footnotes

F1: The sales reported on this Form 4 were pursuant to a 10b5-1 trading plan adopted by the reporting person on March 10, 2016.

F2: Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $104.51 to $105.50 per share.

F3: Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $105.51 to $105.58 per share.

F4: This option was granted pursuant to the 2007 Equity Incentive Plan and is exercisable in 25% cummualtive annual increments beginning March 11, 2014.

F5: This option was granted pursuant to the 2007 Equity Incentive Plan and is exercisable in 25% cummualtive annual increments beginning March 10, 2015.