SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 -------------------------------------------------------------------------------- FORM 11-K/A Amendment No. 1 (Mark One) X ANNUAL REPORT PURSUANT TO SECTION 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 2001 OR TRANSITION REPORT PURSUANT TO SECTION 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ________________ to ________________ Commission file number: 1-8864 A. Full title of plan and the address of the plan, if different from that of the issuer named below: USG CORPORATION INVESTMENT PLAN B. Name of issuer of the securities held pursuant to the plan and the address of its principal executive office: USG Corporation 125 South Franklin Street Chicago, IL 60606-4678 -------------------------------------------------------------------------------- TABLE OF CONTENTS Explanatory Note Signature Exhibit Index Exhibit 23 EXPLANATORY NOTE This Form 11-K/A amends the Form 11-K of the USG Corporation Investment Plan (formerly the USG Corporation Investment Plan for Salaried Employees) filed on March 28, 2002, for the purpose of including the Consent of the Independent Public Accountants attached hereto as Exhibit 23. SIGNATURE The Plan. Pursuant to the requirements of the Securities Exchange Act of 1934, the USG Corporation Pension and Investment Committee has duly caused this amendment to its annual report to be signed on its behalf by the undersigned hereunto duly authorized. USG CORPORATION INVESTMENT PLAN By: /s/ Peter K. Maitland -------------------------- Peter K. Maitland, Plan Administrator Date: June 30, 2003 EXHIBIT INDEX Exhibit No. Description Exhibit 23 Consent of Independent Accountants.