AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON SEPTEMBER 5, 2002 REGISTRATION NO. 333-99147 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 --------------------- AMENDMENT NO. 1 TO FORM S-4 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 --------------------- UNOCAL CORPORATION (Exact name of registrant as specified in its charter) DELAWARE 1311 95-3825062 (State or other Jurisdiction of (Primary Standard Industrial (I.R.S. Employer Incorporation or Organization) Classification Code Number) Identification No.) 2141 ROSECRANS AVENUE, SUITE 4000 EL SEGUNDO, CALIFORNIA 90245 (310) 726-7600 (Address, including zip code, and telephone number, including area code, of registrant's principal executive offices) --------------------- BARRY A. L. HOFFMAN, ESQ. DEPUTY GENERAL COUNSEL UNOCAL CORPORATION 2141 ROSECRANS AVENUE, SUITE 4000 EL SEGUNDO, CALIFORNIA 90245 (310) 726-7600 (Name, address, including zip code, and telephone number, including area code, of agent for service) --------------------- COPY TO: DANIEL A. NEFF, ESQ. ELLIOTT V. STEIN, ESQ. WACHTELL, LIPTON, ROSEN & KATZ 51 WEST 52ND STREET NEW YORK, NEW YORK 10019 (212) 403-1000 APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: As promptly as practicable after this Registration Statement becomes effective and upon consummation of the transactions described herein. If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box. [ ] If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. [ ] ----- If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. [ ] ----- --------------------- CALCULATION OF REGISTRATION FEE --------------------------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------------------------- PROPOSED MAXIMUM PROPOSED MAXIMUM TITLE OF EACH CLASS OF AMOUNT TO OFFERING PRICE AGGREGATE AMOUNT OF SECURITIES TO BE REGISTERED BE REGISTERED PER SHARE OFFERING PRICE REGISTRATION FEE --------------------------------------------------------------------------------------------------------------------------------- Common Stock, par value $1.00 per share (including the associated Preferred Stock Purchase Rights)........................... 15,570,020 shares(1) Not Applicable $553,431,082(2) $50,916(3) --------------------------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------------------------- (1) Represents 50,353,225 outstanding shares of common stock of Pure Resources, Inc. on August 2, 2002 less 32,709,067 shares owned by Union Oil Company of California plus an additional 6,210,630 shares of Pure Resources, Inc. common stock reserved for issuance upon exercise of outstanding stock options on June 30, 2002, multiplied by the exchange ratio of 0.6527. Information as to the number of outstanding shares and stock options of Pure Resources, Inc. has been obtained from Pure Resources, Inc.'s filings with the S.E.C. (2) Reflects the product of (a) $23.20, the market price of the common stock of Pure Resources, Inc. computed in accordance with Rule 457(c) and 457(f) under the Securities Act, based upon the average of the high and low sale prices of the Pure Resources, Inc. common stock as quoted on the New York Stock Exchange on August 28, 2002 and (b) 23,854,788, the maximum number of shares to be acquired pursuant to the offer. The proposed maximum aggregate offering price is estimated solely to determine the registration fee. (3) 0.0092% of the Proposed Maximum Aggregate Offering Price. THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF THE SECURITIES ACT OR UNTIL THIS REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE SECURITIES AND EXCHANGE COMMISSION, ACTING PURSUANT TO SECTION 8(a), MAY DETERMINE. -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- This Amendment No. 1 to the Registration Statement on Form S-4 amends and supplements the Registration Statement on Form S-4 filed by the Registrant with the Securities and Exchange Commission on September 4, 2002, as provided below. All of the offering materials sent to Pure stockholders reflected the amended information provided below. ITEM 4. TERMS OF THE TRANSACTION. Under the title "Selected Historical Financial Data of Unocal and Pure -- Unocal Selected Historical Consolidated Financial Data" appearing on page 5 of the prospectus, the information under the title "Consolidated Income Statement Data: Earnings from continuing operations before minority interests, interest expense and income taxes" is amended and replaced in its entirety as follows: UNOCAL SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA AS OF AND FOR THE SIX MONTHS ENDED JUNE 30, AS OF AND FOR THE YEAR ENDED DECEMBER 31, ----------------- -------------------------------------------- 2002 2001 2001 2000 1999 1998 1997 ------- ------- ------- ------- ------ ------ ------ (DOLLARS IN MILLIONS, EXCEPT PER SHARE AMOUNTS) CONSOLIDATED INCOME STATEMENT DATA: *** Earnings from continuing operations before minority interests, interest expense and income taxes............................ 368 1,024 1,284 1,446 449 445 880 *** SIGNATURES Pursuant to the requirements of the Securities Act, the Registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in El Segundo, California, as of September 5, 2002. UNOCAL CORPORATION By: /s/ TERRY G. DALLAS ------------------------------------ Terry G. Dallas Executive Vice President and Chief Financial Officer The undersigned directors and executive officers of Unocal Corporation appoint Timothy H. Ling, Joe D. Cecil and Darrell D. Chesum and each of them severally our true and lawful attorney with power to sign for us this registration statement and any and all amendments to this registration statement, and generally do all such things in our names and in our capacities as directors to enable Unocal Corporation to comply with the provisions of the Securities Act of 1933 and all requirements of the Securities and Exchange Commission in connection with this offering. Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed below as of September 5, 2002 by the following persons in the capacities indicated: SIGNATURE TITLE --------- ----- /s/ CHARLES R. WILLIAMSON * Chief Executive Officer and Director --------------------------------------------- (Principal Executive Officer) /s/ TIMOTHY H. LING** Chief Operating Officer and Director --------------------------------------------- /s/ JOE D. CECIL** Vice President and Comptroller --------------------------------------------- (Principal Accounting Officer) /s/ JOHN W. AMERMAN** Director* --------------------------------------------- /s/ JOHN W. CREIGHTON, JR.** Director* --------------------------------------------- /s/ JAMES W. CROWNOVER** Director* --------------------------------------------- /s/ FRANK C. HERRINGER** Director* --------------------------------------------- /s/ DONALD B. RICE** Director* --------------------------------------------- --------------- * A majority of the board of directors ** By Joe D. Cecil, Attorney-In-Fact II-4