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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1. Name and Address of Reporting Person * Spivy Gregory P   2. Issuer Name and Ticker or Trading Symbol ARMSTRONG WORLD INDUSTRIES INC [AWI] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director __X__ 10% Owner _____ Officer (give title below) __X__ Other (specify below) See Remarks (Last) (First) (Middle) ONE LETTERMAN DRIVE, BUILDING D, 4TH FLOOR 3. Date of Earliest Transaction (Month/Day/Year) 07/13/2018 (Street) SAN FRANCISCO, CA 94129 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 (1) 07/13/2018   A   1,558 (2) A $ 0 7,295 (3) D (4) (5)   Common Stock               6,852,612 I See Footnotes (5) (6)

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
Spivy Gregory P ONE LETTERMAN DRIVE BUILDING D, 4TH FLOOR SAN FRANCISCO, CA 94129	X	X		See Remarks
ValueAct Holdings, L.P. ONE LETTERMAN DRIVE BUILDING D, 4TH FLOOR SAN FRANCISCO, CA 94129	X	X		See Remarks
ValueAct Capital Master Fund, L.P. ONE LETTERMAN DRIVE BUILDING D, 4TH FLOOR SAN FRANCISCO, CA 94129	X	X		See Remarks
VA Partners I, LLC ONE LETTERMAN DRIVE BUILDING D, 4TH FLOOR SAN FRANCISCO, CA 94129	X	X		See Remarks
ValueAct Capital Management, L.P. ONE LETTERMAN DRIVE BUILDING D, 4TH FLOOR SAN FRANCISCO, CA 94129	X	X		See Remarks
ValueAct Capital Management, LLC ONE LETTERMAN DRIVE BUILDING D, 4TH FLOOR SAN FRANCISCO, CA 94129	X	X		See Remarks
ValueAct Holdings GP, LLC ONE LETTERMAN DRIVE BUILDING D, 4TH FLOOR SAN FRANCISCO, CA 94129	X	X		See Remarks

Signatures

/s/ Gregory P. Spivy		07/17/2018
**Signature of Reporting Person		Date
VALUEACT HOLDINGS, L.P., By: VALUEACT HOLDINGS GP, LLC, its General Partner, By: /s/ Bradley E. Singer, Chief Operating Officer		07/17/2018
**Signature of Reporting Person		Date
VALUEACT CAPITAL MASTER FUND, L.P., By: VA PARTNERS I, LLC, its General Partner, By: /s/ Bradley E. Singer, Chief Operating Officer		07/17/2018
**Signature of Reporting Person		Date
VA PARTNERS I, LLC, By: /s/ Bradley E. Singer, Chief Operating Officer		07/17/2018
**Signature of Reporting Person		Date
VALUEACT CAPITAL MANAGEMENT, L.P., By: VALUEACT CAPITAL MANAGEMENT, LLC, its General Partner, By: /s/ Bradley E. Singer, Chief Operating Officer		07/17/2018
**Signature of Reporting Person		Date
VALUEACT CAPITAL MANAGEMENT, LLC, By: /s/ Bradley E. Singer, Chief Operating Officer		07/17/2018
**Signature of Reporting Person		Date
VALUEACT HOLDINGS GP, LLC, By: /s/ Bradley E. Singer, Chief Operating Officer		07/17/2018
**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)	Restricted stock units granted under the 2016 Directors Stock Unit Plan, as amended, and as part of the Issuer's nonemployee Director Compensation Program. The units vest (contingent upon the Director's continued service as of such date) on the earlier of (i) the one-year anniversary of the grant; (ii) the death or total and permanent disability of the Director; or (iii) the date of any Change in Control Event (as defined in the Plan). Vested units will be acquirable by the Director, at the election of the Director: (i) at the vesting of the units at the one-year anniversary of the grant or (ii) at the time of the Director's termination of service.
(2)	Represents an annual grant of restricted stock units as the equity portion of the Directors retainer for Board service under the Issuer's nonemployee Director Compensation Program. The grant date fair value of the units is calculated under the Financial Accounting Standards Board's Accounting Standards Codification Topic 718 using the closing stock price of the Issuer's common shares on July 13, 2018, the first business day following the Issuer's Annual Meeting of Shareholders, which price was $67.40.
(3)	Includes vested and unvested units as well as units not yet acquirable by the Director. Under the terms of the 2008 Directors Stock Unit Plan, as amended (the "2008 Plan"), vested units under the 2008 Plan are not acquirable by the Director until (i) for those restricted stock units granted prior to June 2011, six (6) months following the termination of service on the Issuer's Board of Directors, and, (ii) for those units granted during and after June 2011, at the time of termination of service on the Issuer's Board of Directors. Under the terms of the 2016 Directors Stock Unit Plan, as amended (the "2016 Plan"), vested units under the 2016 Plan are not acquirable by the Director until, at the election of the Director: (i) the vesting of the units at the one-year anniversary of the grant or (ii) the time of the Director's termination of service.
(4)	The ValueAct entities referred to in this footnote 4 are collectively referred to herein as "ValueAct Capital." Under an agreement with ValueAct Capital, Gregory P. Spivy is deemed to hold the common stock for the benefit of the limited partners of ValueAct Capital Master Fund, L.P. and indirectly for (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.
(5)	Each reporting person listed herein disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that such person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.
(6)	The securities reported herein are directly beneficially owned by ValueAct Capital Master Fund, L.P. and may be deemed to be indirectly beneficially owned by (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.
Remarks: - The reporting persons herein may be deemed to be members of a "group" for purposes of the Securities Exchange Act of 1934, as amended. Each reporting person disclaims beneficial ownership of any securities deemed to be owned by the group that are not directly owned by such reporting person. This report shall not be deemed an admission that such reporting person is a member of a group or the beneficial owner of any securities not directly owned by such reporting person. - Gregory P. Spivy, a Partner at ValueAct Capital, serves on the board of directors of the Issuer. As a result, the other reporting persons herein may be deemed directors by deputization.

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