AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON MARCH 21, 2001 REGISTRATION NO. 333-11897 ================================================================================ SECURITIES AND EXCHANGE COMMISSION --------------- POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-3 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 --------------- OCCIDENTAL PETROLEUM CORPORATION (Exact name of registrant as specified in its charter) DELAWARE 95-4035997 (State or other jurisdiction of (I.R.S. Employer incorporation or organization) Identification No.) 10889 WILSHIRE BOULEVARD LOS ANGELES, CALIFORNIA 90024 (310) 208-8800 (Address, including zip code, and telephone number, including area code, of registrant's principal executive offices) DONALD P. DE BRIER, ESQ. GENERAL COUNSEL OCCIDENTAL PETROLEUM CORPORATION 10889 WILSHIRE BOULEVARD LOS ANGELES, CALIFORNIA 90024 (310) 443-6176 (Name, address, including zip code, and telephone number, including area code, of agent for service) --------------- Copy to: STEVEN R. MACKEY, ESQ. GENERAL COUNSEL HELMERICH & PAYNE, INC. 1579 E. 21ST STREET TULSA, OKLAHOMA 74114 ================================================================================ PART II INFORMATION NOT REQUIRED IN PROSPECTUS EXPLANATORY STATEMENT This filing constitutes Post-Effective Amendment No. 1 (this "Amendment") to the Registration Statement on Form S-3 (Registration Number 333-11897) (the "Registration Statement") of Occidental Petroleum Corporation, declared effective by the Securities Exchange Commission on September 16, 1996. Pursuant to this Amendment, Occidental Petroleum Corporation hereby deregisters all 915,000 shares of its common stock, $.20 par value per share (the "Common Stock"), subject to the Registration Statement and not previously sold by the Selling Stockholder in accordance with the plan of distribution described under the caption "Plan of Distribution" set forth in the Prospectus comprising a portion of the Registration Statement. Any such shares of Common Stock have become freely tradable pursuant to paragraph (k) of Rule 144 under the Securities Act of 1933, as amended. The Registration Statement shall have no further force or effect. 1 SIGNATURES Pursuant to the requirements of the Securities Act and Rule 478 thereunder, the Registrant has duly caused this Post-Effective Amendment No. 1 to Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Los Angeles, State of California, on March 21, 2001. OCCIDENTAL PETROLEUM CORPORATION By /s/ DONALD P. DE BRIER ------------------------------------- Donald P. de Brier Executive Vice President General Counsel and Secretary sak\ngo\s3-1amd II-1