X0306 4 2013-06-06 0 0001020569 IRON MOUNTAIN INC IRM 0001190861 DENINGER PAUL F C/O IRON MOUNTAIN INCORPORATED 745 ATLANTIC AVENUE BOSTON MA 02111 1 0 0 0 Common Stock, par value $.01 per share 2013-06-06 4 A 0 3953 0.01 A 11635 D Consists of shares issuable upon the settlement of restricted stock units granted on June 6, 2013. The restricted stock units vest on the one year anniversary of the grant date (or, if earlier, the annual meeting of stockholders that is closest to the one year anniversary). /s/ Sarah Cammarata, under Power of Attorney dated September 9, 2010 from Paul F. Deninger 2013-06-10