X0306 4 2014-11-04 0 0001020569 IRON MOUNTAIN INC IRM 0001618762 Allerton Jennifer C/O IRON MOUNTAIN INCORPORATED ONE FEDERAL STREET BOSTON MA 02110 1 0 0 0 Common Stock, par value $.01 per share 2014-11-04 5 A 0 E 217 A 2889 D This report reflects 217 previously unreported shares (the "Shares") allocated to the Reporting Person on November 4, 2014 in connection with the Reporting Person's receipt of her pro rata portion of a special distribution declared by the Board of Directors of the issuer on September 15, 2014 and paid on November 4, 2014. The Shares are issuable upon the settlement of restricted stock units ("RSUs") granted on September 15, 2014, which RSUs shall 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 August 27, 2014, from Jennifer Allerton 2014-11-06