AMERICAN TOWER CORP /MA/ — Director's Dealing 2017

May 15, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AMERICAN TOWER CORP /MA/ (AMT)
CIK: 0001053507
Period of Report: 2017-05-11

Reporting Person: Sharma Amit (EVP, Asia)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-05-11	Common Stock	M	61096	$44.92	Acquired	177556	Direct
2017-05-11	Common Stock	S	61096	$126.57	Disposed	116460	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-05-11	Option to Purchase Common Stock	$44.92	M	61096	Disposed	2017-12-03	Common Stock (61096)	Direct

Footnotes

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

F2: Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $126.10 to $126.90 per share.

F3: This option was granted pursuant to the 2007 Equity Incentive Plan, as amended, and is exercisable in 25% cumulative annual increments beginning December 3, 2008.