As filed with the Securities and Exchange Commission on May 1, 2000 Registration No. 333-24803 SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ----------------------- POST-EFFECTIVE AMENDMENT NO. 1 to FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 ----------------------- IRON MOUNTAIN INCORPORATED (1) (Exact name of registrant as specified in its charter) ----------------------- Delaware 04-3107342 (State or other jurisdiction (I.R.S. Employer of incorporation or organization) Identification Number) 745 Atlantic Avenue Boston, Massachusetts 02111 (617) 535-4766 (Address, including zip code, and telephone number, including area code, of registrant's principal executive offices) -------------------- Iron Mountain Incorporated 1995 Stock Incentive Plan (Full title of the plan) --------------------- C. Richard Reese Chairman of the Board of Directors and Chief Executive Officer Iron Mountain Incorporated 745 Atlantic Avenue Boston, Massachusetts 02111 (617) 535-4766 (Name, address, including zip code, telephone number, including area code, of agent for service) --------------------- Copy to: Susan Forest Barrett, Esq. Sullivan & Worcester LLP One Post Office Square Boston, Massachusetts 02109 (617) 338-2800 --------------------- - ------------------- (1) On February 1, 2000, Iron Mountain Incorporated, a Delaware corporation ("Old Iron Mountain"), merged with and into Pierce Leahy Corp., a Pennsylvania corporation ("Pierce Leahy"). Pierce Leahy survived the merger and immediately changed its name to "Iron Mountain Incorporated," a Pennsylvania corporation ("New Iron Mountain"). This Post-Effective Amendment No. 1 is being filed by New Iron Mountain on behalf of Old Iron Mountain. Deregistration of Common Stock On April 9, 1997, Old Iron Mountain filed a Registration Statement on Form S-8 (Registration No. 333-24803) for the sale of an aggregate of 1,417,354 shares (as adjusted for a 3 for 2 stock split in July 1998) of common stock, par value $.01 per share, of Old Iron Mountain ("Common Stock") under the Iron Mountain Incorporated 1995 Stock Incentive Plan (the "Plan"). On February 1, 2000, Old Iron Mountain merged with and into Pierce Leahy, and New Iron Mountain assumed the obligations of Old Iron Mountain under the Plan. Pursuant to Old Iron Mountain's undertaking in the Registration Statement, this Post-Effective Amendment No. 1 is being filed by New Iron Mountain on behalf of Old Iron Mountain to deregister all shares of Common Stock registered pursuant to the Registration Statement but remaining unsold as of the date this Post-Effective Amendment No. 1 is filed. SIGNATURES Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Post-Effective Amendment No. 1 to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Boston, Commonwealth of Massachusetts, on May 1, 2000. IRON MOUNTAIN INCORPORATED By: /s/ C. Richard Reese C. Richard Reese Chairman and Chief Executive Officer Pursuant to the requirements of the Securities Act of 1933, as amended, this Post-Effective Amendment No. 1 to the Registration Statement has been signed below by the following persons in the capacities and on the dates indicated. Signature Title Date /s/ C. Richard Reese Chairman, Chief Executive May 1, 2000 C. Richard Reese Officer and Director President and Director J. Peter Pierce /s/ John F. Kenny, Jr. Executive Vice President, Chief May 1, 2000 John F. Kenny, Jr. Financial Officer and Director * Vice President and Corporate May 1, 2000 Jean A. Bua Controller (principal accounting officer) Director Clarke H. Bailey * Director May 1, 2000 Constantin R. Boden Director Kent P. Dauten * Director May 1, 2000 Eugene B. Doggett Director May 1, 2000 B. Thomas Golisano * Director May 1, 2000 Arthur D. Little Director Howard D. Ross * Director May 1, 2000 Vincent J. Ryan *By: /s/ C. Richard Reese C. Richard Reese Attorney-in-Fact pursuant to Power of Attorney previously filed as a part of this Registration Statement