X0306 4 2013-03-11 0 0001020569 IRON MOUNTAIN INC IRM 0001032365 REESE C RICHARD 100 BELVIDERE STREET APARTMENT 9F BOSTON MA 02199 1 1 0 0 Executive Chairman Common Stock, par value $.01 per share 2013-03-11 4 A 0 28532 0 A 399164 D Common Stock, par value $.01 per share 2013-03-11 4 F 0 9480 35.31 D 389684 D Common Stock, par value $.01 per share 2891381.553 I By Contract Common Stock, par value $.01 per share 280152 I See Footnote Common Stock, par value $.01 per share 1330625 I See Footnote Restricted Stock Units 2013-03-11 4 D 0 28532 0 D Common Stock 28532 57151 D Performance Units 2013-03-13 4 A 0 76600 0 A Common Stock 76600 76600 D This acquisition is reported to reflect the partial vesting of restricted stock units ("RSUs") previously granted to the Reporting Person. The Reporting Person shares beneficial ownership of these shares with Schooner Capital Corporation as a result of a 1988 deferred compensation arrangement, as amended, between Schooner Capital LLC ("Schooner") and the Reporting Person relating to the Reporting Person's former services as President of the predecessor corporation to Schooner (the "Arrangement"). Pursuant to the Arrangement, the Reporting Person is entitled to receive benefits equivalent to the fair market value of such shares with payments to the Reporting Person commencing on the first business day of 2014 and payable in nine annual installments; however, the Reporting Person has the right to defer the commencement of such installments in certain circumstances. In addition, any unpaid benefits pursuant to this arrangement shall be payable to the Reporting Person's beneficiary(ies) in a lump sum upon his death. Benefits pursuant to this arrangement are payable in cash or, at the Reporting Person's election, Iron Mountain Incorporated common stock ("Common Stock"). These shares are held by the GST Trust. The Reporting Person disclaims beneficial ownership of the GST Trust, and this report should not be deemed an admission that the Reporting Person is beneficial owner of such securities for the purposes of Section 16 of the Exchange Act of 1934, as amended, or for any purpose. These shares are held by the Reese Family 2005 LLC (the "LLC"). The Reporting Person disclaims beneficial ownership of all securities held by the LLC, and this report should not be deemed an admission that the Reporting Person is beneficial owner of such securities for purposes of Section 16 of the Exchange Act of 1934, as amended, or for any purpose. Each RSU represents a contingent right to receive one share of Common Stock. The RSUs, representing a contingent right to receive a total of 85,683 shares of Common Stock, were granted to the Reporting Person on March 9, 2012 and vest in three substantially equal annual installments beginning on the first anniversary of the grant date. The number of RSUs granted includes previously reported RSUs allocated on November 21, 2012 in connection with the Reporting Person's receipt of his pro rata portion of a special dividend declared by the Board of Directors of Iron Mountain Incorporated on October 11, 2012 and paid on November 21, 2012. Each performance unit ("PU") represents a contingent right to receive one share of Common Stock. The PUs were previously granted to the Reporting Person on March 9, 2012, and on March 13, 2013 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 9, 2015, subject to certain exceptions. /s/ Garry B. Watzke, under Power of Attorney dated September 16, 2010 from C. Richard Reese 2013-03-13