FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * FAIRFAX FINANCIAL HOLDINGS LTD/ CAN   2. Issuer Name and Ticker or Trading Symbol USG CORP [USG] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director __X__ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 95 WELLINGTON STREET WEST, SUITE 800 3. Date of Earliest Transaction (Month/Day/Year) 08/23/2012 (Street) TORONTO, ONTARIO, CANADA,  M5J 2N7 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) ___ Form filed by One Reporting Person _X_ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock, $0.10 par value ("Common Shares") 08/23/2012   S   1,000,000 D $ 19.975 5,794,000 I See Footnote (1) Common Shares 08/24/2012   S   1,713,700 D $ 20.631 4,080,300 I See Footnote (1) Common Shares 08/27/2012   S   645,500 D $ 20.618 3,434,800 I See Footnote (1) Common Shares 08/28/2012   S   878,623 D $ 20.377 2,556,177 I See Footnote (1) Common Shares 08/29/2012   S   639,000 D $ 20.472 1,917,177 I See Footnote (1)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
FAIRFAX FINANCIAL HOLDINGS LTD/ CAN 95 WELLINGTON STREET WEST SUITE 800 TORONTO, ONTARIO, CANADA M5J 2N7		X
WATSA V PREM ET AL 95 WELLINGTON STREET WEST SUITE 800 TORONTO, ONTARIO, CANADA M5J 2N7		X
1109519 ONTARIO LTD 95 WELLINGTON STREET WEST SUITE 800 TORONTO, ONTARIO, CANADA M5J 2N7		X
SIXTY TWO INVESTMENT CO LTD 1600 CATHEDRAL PLACE 925 WEST GEORGIA ST. VANCOUVER, BC, CANADA V6C 3L3		X
810679 ONTARIO LTD 95 WELLINGTON STREET WEST SUITE 800 TORONTO, ONTARIO, CANADA M5J 2N7		X
ODYSSEY REINSURANCE CO 300 FIRST STAMFORD PLACE STAMFORD, CT 06902		X
UNITED STATES FIRE INSURANCE CO 305 MADISON AVENUE MORRISTOWN, NJ 07962		X

Signatures

/s/ Paul Rivett, Vice President, Operations		02/13/2013
**Signature of Reporting Person		Date
/s/ V. Prem Watsa		02/13/2013
**Signature of Reporting Person		Date
/s/ V. Prem Watsa, President		02/13/2013
**Signature of Reporting Person		Date
/s/ V. Prem Watsa, President		02/13/2013
**Signature of Reporting Person		Date
/s/ V. Prem Watsa, President		02/13/2013
**Signature of Reporting Person		Date
/s/ Kirk M. Reische, Vice President		02/13/2013
**Signature of Reporting Person		Date
/s/ Paul W. Bassaline, Vice President and Controller		02/13/2013
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	The Common Shares are held by certain subsidiaries of Fairfax Financial Holdings Limited ("Fairfax") as well as by the pension plans of certain subsidiaries of Fairfax, including, immediately following the transactions reported herein, 579,800 Common Shares held by United States Fire Insurance Company and 1,254,477 Common Shares held by Odyssey Reinsurance Company.

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