X0202 4 2004-05-27 0001020569 IRON MOUNTAIN INC/PA IRM 0001183339 LITTLE ARTHUR D P.O. BOX 166 HUNTRESS BRIDGE ROAD S. EFFINGHAM NH 03882 1 0 0 0 Common Stock, par value, $.01 per share 0 D Stock Option (Right to Buy) 44.14 2004-05-27 4 A 0 4531 0 A 2004-05-27 2014-05-27 Common Stock 4531 0 D As of the date of the filing, Mr. Little holds no direct ownership of Iron Mountain Common Stock and holds 30,000 shares indirectly. The indirectly held shares are held by Mr. Little as beneficiary of the Little Family Trust. This option vests 8.33% and fully vests after 12 quarters (5/27/07). Clare A. Dever, under Power of Attorney dated November 14, 2002 from Arthur D. Little 2004-05-28