X0306 4 2017-10-11 0 0001020569 IRON MOUNTAIN INC IRM 0001346840 Keddy Patrick J C/O IRON MOUNTAIN INCORPORATED ONE FEDERAL STREET BOSTON MA 02110 0 1 0 0 Exec.VP,GM,N.America,W.Europe Common Stock, par value $.01 per share 2017-10-11 4 M 0 7011 24.804 A 19599 D Common Stock, par value $.01 per share 2017-10-11 4 S 0 7011 39.142 D 12588 D Common Stock, par value $.01 per share 2017-10-11 4 M 0 16417 29.270 A 29005 D Common Stock, par value $.01 per share 2017-10-11 4 S 0 16417 39.000 D 12588 D Employee Stock Option (Right to Buy) 24.804 2017-10-11 4 M 0 7011 0 D 2024-02-13 Common Stock 7011 0 D Employee Stock Option (Right to Buy) 29.270 2017-10-11 4 M 0 16417 0 D 2026-02-18 Common Stock 16417 32884 D This transaction was effected pursuant to a 10b5-1 trading plan which was approved and became effective as of September 8, 2017. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $39.000 to $39.215, inclusive. The Reporting Person undertakes to provide to Iron Mountain Incorporated (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (2). This stock option, representing a right to purchase a total of 7,011 shares, is fully vested. This stock option, representing a right to purchase a total of 49,301 shares, has vested with respect to 16,417 shares. The remaining shares become exercisable in two substantially equal annual installments beginning on February 18, 2018. /s/ Elizabeth Tammaro, under Power of Attorney dated May 26, 2016, from Patrick Keddy 2017-10-13