Exhibit 3.1 CERTIFICATE OF TRUST OF USX CAPITAL TRUST I This Certificate of Trust of USX Capital Trust I (the "Trust"), dated March 13, 1997, is being duly executed and filed by the undersigned, as trustees, to form a business trust under the Delaware Business Trust Act (12 Del. C. Section 3801 et seq.). 1. Name. The name of the business trust being formed hereby is USX ---- Capital Trust I. 2. Delaware Trustee. The name and business address of the trustee of ---------------- the Trust with a principal place of business in the State of Delaware is The Bank of New York (Delaware), White Clay Center, Rte 273, Newark, DE 19711. 3. Effective Date. This Certificate of Trust shall be effective as -------------- of its filing. IN WITNESS WHEREOF, the undersigned, being all of the trustees of the Trust, have executed this Certificate of Trust as of the date first above written. /s/ A.G. Adkins _______________________________ A.G. Adkins, as Trustee /s/ P.J. Kuntz ______________________________ P.J. Kuntz, as Trustee /s/ M.K. Stewart ______________________________ M.K. Stewart, as Trustee THE BANK OF NEW YORK, as Trustee /s/ Mary La Gumina By______________________________ Name: Mary La Gumina Title: Assistant Vice President 2 THE BANK OF NEW YORK (DELAWARE), as Trustee /s/ Frederick Clark By____________________________ Name: Frederick Clark Title: Authorized Signatory