FORM 8-K SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 _________________________ CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report: April 18, 2000 VASTAR RESOURCES, INC. (exact name of registrant as specified in charter) Delaware 1-13108 95-4446177 (State or other (Commission (IRS Employer jurisdiction of File Number) Identification No.) Incorporation) 15375 Memorial Drive, Houston, Texas 77079 (Address of Principal executive offices) (Zip Code) Registrant's telephone number, including area code: (281) 584-6000 Item 1. Changes in Control of Registrant. On April 18, 2000, the combination of BP Amoco p.l.c. ("BP Amoco") and Atlantic Richfield Company ("ARCO") was completed. As a result of the combination, BP Amoco indirectly owns, through a subsidiary, 81.9 percent of the Common Stock, par value $0.01 per share, of the registrant, Vastar Resources, Inc. (the "Company") and a change of control of the Company has occurred. Simultaneous with the consummation of the merger, the Chairman of the Board of the Company, Michael E. Wiley, and three additional members of the Board of Directors of the Company, Terry G. Dallas, Marie L. Knowles and Donald R. Voelte, Jr., resigned. The Board of Directors thereafter reduced the size of the Board of Directors to five positions which are occupied by the remaining members of the Board of Directors. The Board of Directors also elected Charles D. Davidson as Chairman of the Board. The Board of Directors now consists of the following members: Charles D. Davidson, Chairman, Jimmie D. Callison, Robert C. LeVine, Steven J. Shapiro and William D. Schulte. On March 16, 2000, BP Amoco p.l.c. advised Vastar's Board of Directors of its intention to commence a $71.00 per share tender offer to purchase the approximately 17.6 million shares, or 18.1 percent, of Vastar's common stock that are publicly traded. The proposal was conditional on the completion of BP Amoco's acquisition of ARCO. Vastar has formed a special committee of independent directors to evaluate the proposal. Item 5. Other Events. Attached as Exhibit 99 to this Form 8-K is a press release announcing the resignation of certain members of the Board of Directors and election of a new Chairman of the Board. 2 SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, Vastar Resources, Inc. has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. VASTAR RESOURCES, INC. (Registrant) Dated: April 18, 2000 /s/ Joseph P. McCoy ___________________________ (signature) Joseph P. McCoy Vice President and Controller (Duly Authorized Officer and Principal Accounting Officer) 3 EXHIBIT INDEX Exhibit No. Description _______ ___________ 99 Press Release Dated April 18, 2000. 4