X0306 4 2014-03-17 0 0001020569 IRON MOUNTAIN INC IRM 0001291613 Cloutier Ernest W C/O IRON MOUNTAIN INCORPORATED ONE FEDERAL STREET BOSTON MA 02110 0 1 0 0 EVP, Gen. Counsel, Secretary Common Stock, par value $.01 per share 2014-03-17 4 A 0 2755 0 A 14165 D Common Stock, par value $.01 per share 2014-03-17 4 F 0 896 27.66 D 13269 D Restricted Stock Units 2014-03-17 4 D 0 2755 0 D Common Stock 2755 5520 D This acquisition is reported to reflect the partial vesting of restricted stock units ("RSUs") previously granted to the Reporting Person on March 15, 2013. Each RSU represents a contingent right to receive one share of Iron Mountain Incorporated common stock ("Common Stock"). The RSUs, representing a contingent right to receive a total of 8,275 shares of Common Stock, were granted to the Reporting Person on March 15, 2013 and vest in three substantially equal annual installments beginning on the first anniversary of the grant date. /s/ Sarah Cammarata, under Power of Attorney dated November 1, 2013, from Ernest W. Cloutier 2014-03-19