EXHIBIT 3.1.12 CERTIFICATE OF AMENDMENT TO THE CERTIFICATE OF INCORPORATION OF RANGE RESOURCES CORPORATION ----------------------------------------------------------------- (PURSUANT TO SECTION 242 OF THE DELAWARE GENERAL CORPORATION LAW) ----------------------------------------------------------------- Range Resources Corporation, a Delaware corporation (the "Corporation"), DOES HEREBY CERTIFY: FIRST: The name of the Corporation is RANGE RESOURCES CORPORATION. SECOND: The amendment to the Certificate of Incorporation of the Corporation effected by this certificate shall provide: that the number of authorized shares of the Corporation's Common Stock be increased from 50 million shares to 100 million shares. THIRD: To accomplish the foregoing amendment, the present Article FOURTH is hereby amended to read in its entirety as follows: FOURTH: (1) The total number of shares of all classes of stock that the Corporation shall have authority to issue is 110 million shares, divided into classes as follows: 100 million Common shares having a par value of $.0l per share; and 10 million Preferred shares having a par value of $1.00 per share. (2) No holder of shares of the Corporation shall have any preemptive right to subscribe for or to purchase any shares of the Corporation of any class whether now or hereafter authorized. FOURTH: The above amendment to the Certificate of Incorporation of the Corporation was duly adopted by the unanimous approval of the Board of Directors of the Corporation and has been duly approved by the stockholders owning more than a majority of the Corporation's outstanding shares of stock entitled to vote in accordance with the provisions of Section 242 of the General Corporation Law of the State of Delaware or otherwise. IN WITNESS WHEREOF, said Range Resources Corporation has caused the Certificate to be signed by John H. Pinkerton, President and Chief Executive Officer, and attested by Rodney L. Waller, its Senior Vice President and Secretary, as of the 24th day of May, 2000. RANGE RESOURCES CORPORATION By: /s/ JOHN H. PINKERTON -------------------------------------- John H. Pinkerton President and Chief Executive Officer ATTEST: By: /s/ RODNEY L. WALLER --------------------------------- Rodney L. Waller Senior Vice President and Secretary