1 As filed with the Securities and Exchange Commission on January 11, 2001 Registration No. 333-63439 ================================================================================ SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 --------------------- POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-3 Registration Statement Under the Securities Act of 1933 --------------------- ASPEN TECHNOLOGY, INC. (Exact name of registrant as specified in its charter) --------------------- DELAWARE 04-2739697 (State or other jurisdiction of (I.R.S. Employer Identification No.) incorporation or organization) Ten Canal Park Cambridge, Massachusetts 02141 (617) 949-1000 (Address, including zip code, and telephone number, including area code, of registrant's principal executive offices) --------------------- LAWRENCE B. EVANS Chairman of the Board and Chief Executive Officer Aspen Technology, Inc. Ten Canal Park Cambridge, Massachusetts 02141 (617) 949-1000 (Name, address, including zip code, and telephone number, including area code, of agent for service) --------------------- Copies to: MICHAEL J. MUSCATELLO, ESQ. MARK L. JOHNSON, ESQ. General Counsel Hale and Dorr LLP Aspen Technology, Inc. 60 State Street Ten Canal Park Boston, Massachusetts 02109 Cambridge, Massachusetts 02141 Telephone: (617) 526-6000 Telephone: (617) 949-1000 Fax: (617) 526-5000 Fax: (617) 949-1717 ================================================================================
2 This registrant hereby withdraws from registration all of its 5 1/4% convertible subordinated debentures due June 15, 2005 registered pursuant to its registration statement on Form S-3 (registration number 333-63439) and not sold as of the time of filing of this Post-Effective Amendment No. 1.
3 SIGNATURES Pursuant to the requirements of the Securities Act of 1933, the registrant has duly caused this Post-Effective Amendment No. 1 to Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Cambridge, Commonwealth of Massachusetts, as of January 10, 2001. ASPEN TECHNOLOGY, INC. By: /s/ Lisa A. Zappala -------------------------------------- Lisa A. Zappala Senior Vice President and Chief Financial Officer Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment No. 1 to Registration Statement has been signed as of January 10, 2001 by the following persons in the capacities indicated. Signature Title --------- ----- * Chairman of the Board and Chief Executive - -------------------------------- Officer (Principal Executive Officer) Lawrence B. Evans /s/ Lisa W. Zappala Senior Vice President and Chief Financial - -------------------------------- Officer (Principal Financial and Lisa W. Zappala Accounting Officer) * Director - -------------------------------- Joseph F. Boston * Director - -------------------------------- Gresham T. Brebach, Jr. * Director - -------------------------------- Douglas R. Brown Director - -------------------------------- Stephen L. Brown Director - -------------------------------- Stephen M. Jennings - -------------------------------- Director Joan C. McArdle *By: /s/ Lisa W. Zappala ---------------------------- Lisa W. Zappala Attorney-in-fact