SCHEDULE 13D/A

(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO RULE 13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO

RULE 13d-2(a)

(Amendment No. 15)

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box o.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended (“Securities Exchange Act”) or otherwise subject to the liabilities of that section of the Securities Exchange Act but shall be subject to all other provisions of the Securities Exchange Act.

(Continued on following pages)

*  Based on 139,652,659 shares of the Common Stock outstanding as of March 31, 2018, as reported in the Issuer’s Form 10-Q filed with the U.S. Securities and Exchange Commission on April 25, 2018, for the quarterly period ended March 31, 2018.

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*  Based on 139,652,659 shares of the Common Stock outstanding as of March 31, 2018, as reported in the Issuer’s Form 10-Q filed with the U.S. Securities and Exchange Commission on April 25, 2018, for the quarterly period ended March 31, 2018.

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This is Amendment No. 15 to the Schedule 13D filed by certain of the Reporting Persons with the Securities and Exchange Commission on October 27, 2000, as subsequently amended (the “Schedule 13D”), with respect to the shares of Common Stock, par value $0.10 per share (“Common Stock”), of USG Corporation (the “Issuer”).  Capitalized terms used herein without definition have the meanings assigned to such terms in the Schedule 13D.

Item 4 is hereby amended to add the following:

On May 1, 2018, Gebr. Knauf KG (“Knauf”) issued a press release commenting on USG Corporation’s willingness to enter into a confidentiality agreement to facilitate discussions regarding Knauf’s $42 per share cash offer.  A copy of this press release is attached as Exhibit 99.1 and incorporated herein by reference.

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

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