SC 13D/A

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

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. 10)

USG Corporation

(Name of Issuer)

Common Stock, Par Value $0.10 Per Share

(Title of Class of Securities)

90329405

(CUSIP Number)

Jorg Schanow, LL.M.

General Counsel

Gebr. Knauf KG

Am Bahnhof 7

97346 Iphofen

Federal Republic of Germany

(49) 9329-31-1091

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

April 16, 2018

(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)

CUSIP No.   90329405					13D
	1	Names of Reporting Persons I.R.S. Identification Nos. of Above Persons [Entities Only] Gebr. Knauf KG
	2	Check the Appropriate Box if a Member of a Group
		(a)		o
		(b)		o
	3	SEC Use Only
	4	Source of Funds WC
	5	Check Box if Disclosure of Legal Proceedings Is Required Pursuant to Item 2(d) or 2(e)  o
	6	Citizenship or Place of Organization Federal Republic of Germany
Number of Shares Beneficially Owned by Each Reporting Person With			Sole Voting Power 14,757,258
			Shared Voting Power -0-
			Sole Dispositive Power 14,757,258
			Shared Dispositive Power -0-
	11	Aggregate Amount Beneficially Owned by Each Reporting Person 14,757,258
	12	Check Box if the Aggregate Amount in Row (11) Excludes Certain Shares o
	13	Percent of Class Represented by Amount in Row (11) 10.53%*
	14	Type of Reporting Person PN

*  Based on 140,131,719 shares of the Common Stock outstanding as of March 12, 2018, as reported in the Issuer’s Definitive Proxy Statement filed with the U.S. Securities and Exchange Commission on March 29, 2018.

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CUSIP No.   90329405					13D
	1	Names of Reporting Persons I.R.S. Identification Nos. of Above Persons [Entities Only] C & G Verwaltungs GmbH
	2	Check the Appropriate Box if a Member of a Group
		(a)		o
		(b)		o
	3	SEC Use Only
	4	Source of Funds AF
	5	Check Box if Disclosure of Legal Proceedings Is Required Pursuant to Item 2(d) or 2(e)  o
	6	Citizenship or Place of Organization Federal Republic of Germany
Number of Shares Beneficially Owned by Each Reporting Person With			Sole Voting Power 14,757,258
			Shared Voting Power -0-
			Sole Dispositive Power 14,757,258
			Shared Dispositive Power -0-
	11	Aggregate Amount Beneficially Owned by Each Reporting Person 14,757,258
	12	Check Box if the Aggregate Amount in Row (11) Excludes Certain Shares o
	13	Percent of Class Represented by Amount in Row (11) 10.53%*
	14	Type of Reporting Person CO

*  Based on 140,131,719 shares of the Common Stock outstanding as of March 12, 2018, as reported in the Issuer’s Definitive Proxy Statement filed with the U.S. Securities and Exchange Commission on March 29, 2018.

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This Amendment No. 10 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.	Purpose of Transaction.
Item 4 is hereby amended to add the following:
On April 16, 2018, Gebr. Knauf KG delivered a letter to the Board of Directors of the Issuer.  A copy of the letter is attached as Exhibit 99.1 and incorporated herein by reference.
Item 7.	Material to be Filed as Exhibits.
99.1Letter dated April 16, 2018.

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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.

April 16, 2018
GEBR. KNAUF KG
/s/ Alexander Knauf
	Alexander Knauf
	General Partner
C & G VERWALTUNGS GMBH
/s/ Jörg Schanow
	Jörg Schanow
	General Manager

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EX-99.1

Exhibit 99.1

April 16, 2018

USG Corporation

550 West Adams Street

Chicago, IL 60661-3676

Attn: Steven F. Leer, Chairman of the Board of Directors

Michelle M. Warner, Senior Vice President, General Counsel and Corporate Secretary

Dear Members of the USG Board of Directors:

As a long-term shareholder of USG, we were deeply troubled that USG chose to deny our request for the Company’s current stocklist materials — a routine matter that merely levels the playing field — so that we may communicate with our fellow USG shareholders. Questioning Knauf’s ownership of USG stock and whether we have “proper purpose” for requesting these materials are the tactics of an entrenched management trying to thwart our right to communicate with fellow stockholders in connection with the annual meeting. These tactics are effectively preventing stockholders from sending a clear message to the Board regarding its refusal to engage related to Knauf’s offer to purchase all outstanding shares of USG for $42.00 per share in cash.

We believe USG’s actions clearly violate our rights as a stockholder under Delaware law. If USG continues to deny or delay its response to our request, we will unfortunately have no choice but to commence an action in the Delaware courts to compel the prompt production of the requested information.

We write to the Board to ask whether you were made aware and whether you approved of these actions. We believe it is highly inappropriate for USG to engage in conduct designed to delay or restrict our communications with the actual owners of USG. We hope you share our disappointment in these obstructive actions, which raise significant legal and corporate governance concerns and needlessly waste corporate cash.

However troubling, we will not be distracted by USG’s latest actions. Our $42 offer presents an immediate, high-value and cash-certain monetization opportunity for USG shareholders after a significant period of time without dividends or equivalent share price development. As the Board is aware, our offer has received public support from USG’s largest shareholder and we remain unwavering in our focus to engage with all fellow shareholders and bring this transaction to fruition.

We would have hoped to have a constructive discussion directly with USG, and we still do. However, USG’s numerous refusals to meaningfully engage with us despite our best efforts and the Company’s attempts to restrict shareholder dialogue has forced us to continue to pursue the path of a withhold campaign, during which we are asking stockholders to vote against the reelection of the USG’s director nominees as a message of frustration and disappointment with the entrenchment tactics employed by the Board and management. Nevertheless, it remains our strong preference to engage in constructive dialogue with USG to quickly reach an agreement on definitive documentation.

We look forward to the possibility of consummating a transaction in the near future.

Very truly yours,
Alexander Knauf	Manfred Grundke
General Partner	General Partner