IRON MOUNTAIN INC — Director's Dealing 2016

May 4, 2016

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: IRON MOUNTAIN INC (IRM)
CIK: 0001020569
Period of Report: 2016-05-02

Reporting Person: BAILEY CLARK H (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2016-05-02	Common Stock, par value $.01 per share	M	9772	$19.947	Acquired	161367	Direct
2016-05-02	Common Stock, par value $.01 per share	S	6868	$37.07	Disposed	154499	Direct
2016-05-02	Common Stock, par value $.01 per share	S	2904	$37.08	Disposed	151595	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2016-05-02	Employee Stock Option (Right to Buy)	$19.947	M	9772	Disposed	2016-05-24	Common Stock (9772)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock, par value $.01 per share	12409	Indirect
Common Stock, par value $.01 per share	12409	Indirect

Footnotes

F1: This amount has been reduced by one (1) share to correct a rounding error with respect to the number of shares of Iron Mountain common stock acquired by the Reporting Person on November 4, 2014 as a result of the Reporting Person's receipt of his pro rata portion of the special distribution declared by the Board of Directors of Iron Mountain Incorporated on September 15, 2014 and paid on November 4, 2014.

F2: Shares held by the Clarke H. Bailey GST Trust for the benefit of Trent S. Bailey.

F3: Shares held by the Clarke H. Bailey GST Trust for the benefit of Turner H. Bailey.

F4: This stock option, representing a right to purchase a total of 9,772 shares, is fully vested. The number of stock options granted includes previously reported adjustments effective on September 26, 2014 made in connection with the special distribution declared by the Board of Directors of the Issuer on September 15, 2014 and paid on November 4, 2014.