As filed with the Securities and Exchange Commission on May 24, 2001 Registration No. 333-_____ ================================================================================ UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 ------------------- POST-EFFECTIVE AMENDMENT NO. 1 FORM S-8 REGISTRATION STATEMENT Under The Securities Act of 1933 ------------------- ARIBA, INC. (Exact name of registrant as specified in its charter) DELAWARE 7372 77-0439730 (State or other jurisdiction of (Primary Standard Industrial (IRS Employer incorporation or organization) Classification Code Number) Identification No.) 807 11th Avenue Sunnyvale, CA 94089 (650) 390-1000 (Address of principal executive offices) (Zip Code) ------------------- 1999 Equity Incentive Plan Employee Stock Purchase Plan (Full title of the Plans) ------------------- Robert M. Calderoni Chief Financial Officer, Executive Vice President Finance and Administration ARIBA, INC. 807 11th Avenue Sunnyvale, CA 94089 (Name and address of agent for service) (650) 390-1000 (Telephone number, including area code, of agent for service) ------------------- This Post-Effective Amendment No. 1 to the Registration Statement shall hereafter become effective in accordance with the provisions of Section 8(c) of the Securities Act of 1933, as amended. PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT Item 8. Exhibits -------- Exhibit Number Exhibit - -------------- ------- 4* Instrument Defining Rights of Stockholders. 5* Opinion and consent of Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP. 23.1 Consent of Independent Auditors. 23.2* Consent of Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP is contained in Exhibit 5. 24* Power of Attorney. *Incorporated by reference to Registration Statement No. 333-61064 on Form S-8 filed with the SEC on May 16, 2001. II-1 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 Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Sunnyvale, State of California on this 24th day of May, 2001. ARIBA, INC. By: /s/Larry Mueller* ------------------------------------------- Larry Mueller President and Chief Executive Officer Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed below by the following persons in the capacities and on the dates indicated. Signature Title Date - --------- ----- ---- /s/Larry Mueller* President and Chief Executive Officer May 24, 2001 - -------------------------------- (Principal Executive Officer) Larry Mueller /s/Robert M. Calderoni* Chief Financial Officer, Executive Vice May 24, 2001 - -------------------------------- President-Finance and Administration Robert M. Calderoni (Principal Financial and Accounting Officer) and Secretary /s/Robert C. Kagle* Director May 24, 2001 - -------------------------------- Robert C. Kagle /s/Paul Hegarty* Director May 24, 2001 - -------------------------------- Paul Hegarty /s/Masayoshi Son* Director May 24, 2001 - -------------------------------- Masayoshi Son Director May 24, 2001 ________________________________ Hatim A. Tyabji /s/Robert E. Knowling, Jr.* Director May 24, 2001 - -------------------------------- Robert E. Knowling, Jr. /s/Keith Krach* Chairman of the Board May 24, 2001 - -------------------------------- Keith Krach *By: /s/ Robert M. Calderoni May 24, 2001 - -------------------------------- Robert M. Calderoni Attorney-in-Fact II-2 EXHIBIT INDEX Exhibit Number Exhibit - -------------- ------- 4* Instrument Defining Rights of Stockholders. 5* Opinion and consent of Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP. 23.1 Consent of Independent Auditors. 23.2* Consent of Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP is contained in Exhibit 5. 24* Power of Attorney. *Incorporated by reference to Registration Statement No. 333-61064 on Form S-8 filed with the SEC on May 16, 2001.