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

May 9, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

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

Reporting Person: SHARBUTT DAVID E (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-05-05	Common Stock	M	4167	$43.11	Acquired	10612	Direct
2017-05-05	Common Stock	S	4167	$127.77	Disposed	6445	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-05-05	Option to Purchase Common Stock	$43.11	M	4167	Disposed	2020-03-10	Common Stock (4167)	Direct

Footnotes

F1: Represents the weighted average price of shares sold in multiple same-day transactions at prices ranging from $127.75 to $127.82 per share.

F2: This option was granted pursuant to the 2007 Equity Incentive Plan, as amended.