X0304 4 2012-03-07 0 0001020569 IRON MOUNTAIN INC IRM 0001396523 Duale Marc A THIRD FLOOR, COTTONS CENTRE TOOLEY STREET LONDON X0 SE1 2TT UNITED KINGDOM 0 1 0 0 President, Iron Mountain Int'l Common Stock, par value $.01 per share 2012-03-11 4 A 0 1066 0 A 1066 D Common Stock, par value $.01 per share 2012-03-11 4 F 0 48 28.74 D 1018 D Performance Units 2012-03-07 4 A 0 7088 0 A Common Stock 7088 7088 D Restricted Stock Units 2012-03-09 4 A 0 10396 0 A Common Stock 10396 10396 D Restricted Stock Units 2012-03-11 4 D 0 1066 0 A Common Stock 1066 2136 D This acquisition is reported to reflect the partial vesting of restricted stock units ("RSUs") previously granted to the reporting person. Each performance unit ("PU") represents a contingent right to receive one share of Iron Mountain Incorporated common stock. The PUs were previously granted to the reporting person on March 11, 2011, and on March 7, 2012 the Compensation Committee of Iron Mountain Incorporated's Board of Directors determined the actual award of PUs under the grant after completion of the relevant performance period. The PUs fully vest on March 11, 2014, subject to certain exceptions, if the officer is, as of that date, continuing to perform services for Iron Mountain Incorporated. Each RSU represents a contingent right to receive one share of Iron Mountain Incorporated common stock. The RSUs vest in three annual installments beginning on the first anniversary of the date of grant. The RSUs, representing a right to purchase a total of 3,202 shares of Iron Mountain Incorporated common stock, were granted in March 2011 and vest in three annual installments beginning on March 11, 2012, which was the first anniversary of the date on which the RSUs were granted. /s/ Sarah Cammarata, under Power of Attorney dated December 2, 2010, from Marc A. Duale 2012-03-13