============================================================================= UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities and Exchange Act of 1934 (Amendment No. 4) Allison Transmission Holdings, Inc. ------------------------------------------------ (Name of Issuer) Common Stock ------------------------------------------------ (Title of Class of Securities) 01973R101 ------------------------------------------------ (CUSIP Number) Allison Bennington, Esq. ValueAct Capital One Letterman Drive, Building D, Fourth Floor San Francisco, CA 94129 (415) 362-3700 ------------------------------------------------ (Name, address and telephone number of Person Authorized to Receive Notices and Communications) Allison Bennington, Esq. ValueAct Capital One Letterman Drive, Building D, Fourth Floor San Francisco, CA 94129 (415) 362-3700 November 17, 2016 ------------------------------------------------ (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 that is the subject of this Schedule 13D, and is filing this schedule because of 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box [ ]. Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 240.13d-7 for other parties to whom copies are to be sent. *The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page. This 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 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes). ============================================================================= SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 2 of 12 ----------------------------------------------------------------------------- 1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE PERSON (entities only) ValueAct Capital Master Fund, L.P. ----------------------------------------------------------------------------- 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [X] (b) [ ] ----------------------------------------------------------------------------- 3. SEC USE ONLY ----------------------------------------------------------------------------- 4. SOURCE OF FUNDS (See Instructions)* WC* ----------------------------------------------------------------------------- 5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ----------------------------------------------------------------------------- 6. CITIZENSHIP OR PLACE OF ORGANIZATION British Virgin Islands ----------------------------------------------------------------------------- 7. SOLE VOTING POWER 0 NUMBER OF ---------------------------------------------------------- SHARES 8. SHARED VOTING POWER BENEFICIALLY 10,525,204** OWNED BY EACH ---------------------------------------------------------- PERSON WITH 9. SOLE DISPOSITIVE POWER 0 ---------------------------------------------------------- 10. SHARED DISPOSITIVE POWER 10,525,204** ----------------------------------------------------------------------------- 11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 10,525,204** ----------------------------------------------------------------------------- 12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES [ ] ----------------------------------------------------------------------------- 13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 6.4% ----------------------------------------------------------------------------- 14. TYPE OF REPORTING PERSON PN ----------------------------------------------------------------------------- *See Item 3 **See Item 2 and 5 SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 3 of 12 ---------------------------------------------------------------------------- 1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE PERSON (entities only) VA Partners I, LLC ----------------------------------------------------------------------------- 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [X] (b) [ ] ----------------------------------------------------------------------------- 3. SEC USE ONLY ----------------------------------------------------------------------------- 4. SOURCE OF FUNDS* 00* ----------------------------------------------------------------------------- 5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ----------------------------------------------------------------------------- 6. CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ----------------------------------------------------------------------------- 7. SOLE VOTING POWER 0 NUMBER OF ---------------------------------------------------------- SHARES 8. SHARED VOTING POWER BENEFICIALLY 10,525,204** OWNED BY EACH ---------------------------------------------------------- PERSON WITH 9. SOLE DISPOSITIVE POWER 0 ---------------------------------------------------------- 10. SHARED DISPOSITIVE POWER 10,525,204** ----------------------------------------------------------------------------- 11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 10,525,204** ----------------------------------------------------------------------------- 12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES [ ] ----------------------------------------------------------------------------- 13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 6.4% ----------------------------------------------------------------------------- 14. TYPE OF REPORTING PERSON 00 (LLC) ----------------------------------------------------------------------------- *See Item 3 **See Item 2 and 5 SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 4 of 12 ---------------------------------------------------------------------------- 1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE PERSON (entities only) ValueAct Capital Management, L.P. ----------------------------------------------------------------------------- 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [X] (b) [ ] ----------------------------------------------------------------------------- 3. SEC USE ONLY ----------------------------------------------------------------------------- 4. SOURCE OF FUNDS* 00* ----------------------------------------------------------------------------- 5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ----------------------------------------------------------------------------- 6. CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ----------------------------------------------------------------------------- 7. SOLE VOTING POWER 0 NUMBER OF ---------------------------------------------------------- SHARES 8. SHARED VOTING POWER BENEFICIALLY 10,525,204** OWNED BY EACH ---------------------------------------------------------- PERSON WITH 9. SOLE DISPOSITIVE POWER 0 ---------------------------------------------------------- 10. SHARED DISPOSITIVE POWER 10,525,204** ----------------------------------------------------------------------------- 11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 10,525,204** ----------------------------------------------------------------------------- 12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES [ ] ----------------------------------------------------------------------------- 13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 6.4% ----------------------------------------------------------------------------- 14. TYPE OF REPORTING PERSON PN ----------------------------------------------------------------------------- *See Item 3 **See Item 2 and 5 SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 5 of 12 ---------------------------------------------------------------------------- 1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE PERSON (entities only) ValueAct Capital Management, LLC ----------------------------------------------------------------------------- 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [X] (b) [ ] ----------------------------------------------------------------------------- 3. SEC USE ONLY ----------------------------------------------------------------------------- 4. SOURCE OF FUNDS* 00* ----------------------------------------------------------------------------- 5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ----------------------------------------------------------------------------- 6. CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ----------------------------------------------------------------------------- 7. SOLE VOTING POWER 0 NUMBER OF ---------------------------------------------------------- SHARES 8. SHARED VOTING POWER BENEFICIALLY 10,525,204** OWNED BY EACH ---------------------------------------------------------- PERSON WITH 9. SOLE DISPOSITIVE POWER 0 ---------------------------------------------------------- 10. SHARED DISPOSITIVE POWER 10,525,204** ----------------------------------------------------------------------------- 11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 10,525,204** ----------------------------------------------------------------------------- 12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES [ ] ----------------------------------------------------------------------------- 13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 6.4% ----------------------------------------------------------------------------- 14. TYPE OF REPORTING PERSON 00 (LLC) ----------------------------------------------------------------------------- *See Item 3 **See Item 2 and 5 SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 6 of 12 ----------------------------------------------------------------------------- 1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE PERSON (entities only) ValueAct Holdings, L.P. --------------------------------------------------------------------------- 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [X] (b) [ ] ----------------------------------------------------------------------------- 3. SEC USE ONLY --------------------------------------------------------------------------- 4. SOURCE OF FUNDS* 00* ----------------------------------------------------------------------------- 5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ----------------------------------------------------------------------------- 6. CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ----------------------------------------------------------------------------- 7. SOLE VOTING POWER 0 NUMBER OF ---------------------------------------------------------- SHARES 8. SHARED VOTING POWER BENEFICIALLY 10,525,204** OWNED BY EACH ---------------------------------------------------------- PERSON WITH 9. SOLE DISPOSITIVE POWER 0 ---------------------------------------------------------- 10. SHARED DISPOSITIVE POWER 10,525,204** ----------------------------------------------------------------------------- 11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 10,525,204** ----------------------------------------------------------------------------- 12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES [ ] ----------------------------------------------------------------------------- 13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 6.4% ----------------------------------------------------------------------------- 14. TYPE OF REPORTING PERSON PN ----------------------------------------------------------------------------- *See Item 3 **See Items 2 and 5 SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 7 of 12 ----------------------------------------------------------------------------- 1. NAME OF REPORTING PERSON/S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE PERSON (entities only) ValueAct Holdings GP, LLC --------------------------------------------------------------------------- 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [X] (b) [ ] ----------------------------------------------------------------------------- 3. SEC USE ONLY ----------------------------------------------------------------------------- 4. SOURCE OF FUNDS* 00* ----------------------------------------------------------------------------- 5. CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ----------------------------------------------------------------------------- 6. CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ----------------------------------------------------------------------------- 7. SOLE VOTING POWER 0 NUMBER OF ---------------------------------------------------------- SHARES 8. SHARED VOTING POWER BENEFICIALLY 10,525,204** OWNED BY EACH ---------------------------------------------------------- PERSON WITH 9. SOLE DISPOSITIVE POWER 0 ---------------------------------------------------------- 10. SHARED DISPOSITIVE POWER 10,525,204** ----------------------------------------------------------------------------- 11. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 10,525,204** ----------------------------------------------------------------------------- 12. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES [ ] ----------------------------------------------------------------------------- 13. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 6.4% ----------------------------------------------------------------------------- 14. TYPE OF REPORTING PERSON 00 (LLC) ----------------------------------------------------------------------------- *See Item 3 **See Items 2 and 5 SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 8 of 12 ----------------------------------------------------------------------------- This Amendment No. 4 supplements the information set forth in the Schedule 13D filed by the Reporting Persons with the United States Securities and Exchange Commission (the "SEC") on November 13, 2013, as amended from time to time (the "Schedule 13D"), relating to Common Stock (the "Common Stock"), of Allison Transmission Holdings, Inc., a Delaware corporation (the "Issuer"). All capitalized terms contained herein but not otherwise defined shall have the meanings ascribed to such terms in the Schedule 13D. The information set forth in response to each separate Item below shall be deemed to be a response to all Items where such information is relevant. The Schedule 13D is hereby supplementally amended as follows: Item 5. Interest in Securities of the Issuer (a) and (b). Set forth below is the beneficial ownership of shares of Common Stock of the Issuer for each person named in Item 2. Shares reported as beneficially owned by ValueAct Master Fund are also reported as beneficially owned by (i) ValueAct Management L.P. as the manager of each such investment partnership, (ii) ValueAct Management LLC, as General Partner of ValueAct Management L.P., (iii) ValueAct Holdings, as the sole owner of the limited partnership interests of ValueAct Management L.P. and the membership interests of ValueAct Management LLC and as the majority owner of the membership interests of VA Partners I and (iv) ValueAct Holdings GP, as General Partner of ValueAct Holdings. Shares reported as beneficially owned by ValueAct Master Fund are also reported as beneficially owned by VA Partners I, as General Partner of ValueAct Master Fund. VA Partners I, ValueAct Management L.P., ValueAct Management LLC, ValueAct Holdings and ValueAct Holdings GP also, directly or indirectly, may own interests in one or more than one of the partnerships from time to time. Unless otherwise indicated below, by reason of such relationship ValueAct Master Fund is reported as having shared power to vote or to direct the vote, and shared power to dispose or direct the disposition of, such shares of Common Stock, with VA Partners I (only with respect to ValueAct Master Fund), ValueAct Management L.P., ValueAct Management LLC, ValueAct Holdings and ValueAct Holdings GP. As of the date hereof, the Reporting Persons beneficially own 10,525,204 shares of Common Stock, representing approximately 6.4% of the Issuer's outstanding Common Stock. All percentages set forth in this Schedule 13D are based upon the Issuer's reported 165,384,097 outstanding shares of Common Stock as of October 11, 2016, as reported in the Issuer's Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2016. (c) The following table sets forth all transactions with respect to shares of Common Stock effected since the most recent filing of the Schedule 13D by the Reporting Persons or on behalf of the Reporting Persons in respect of the Common Stock, inclusive of any transactions effected through 4:00 p.m., New York City time, on November 21, 2016. Except as otherwise noted below, all such transactions were purchases (or sales) of shares of Common Stock effected in the open market. SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 9 of 12 ----------------------------------------------------------------------------- Reporting Person Trade Date Buy/Sell Bought(Sold) Price/Share ---------------- ---------- -------- ------------ ----------- ValueAct Master Fund 11/17/2016 Sell (2,900,000) $31.78 11/21/2016 Sell (1,400,000) $32.34 (d) and (e) Not applicable. Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer Other than as described in this Schedule 13D and as previously reported, the Reporting Persons have no understandings, arrangements, relationships or contracts relating to the Issuer's Common Stock which are required to be described hereunder. Item 7. Material to Be Filed as Exhibits (1) Joint Filing Agreement. SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 10 of 12 ----------------------------------------------------------------------------- SIGNATURE After reasonable inquiry and to the best of his knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct. POWER OF ATTORNEY KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below on this Schedule 13D hereby constitutes and appoints Jeffrey W. Ubben, Bradley E. Singer, G. Mason Morfit and Allison Bennington, and each of them, with full power to act without the other, his or its true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him or it and in his or its name, place and stead, in any and all capacities (until revoked in writing) to sign any and all amendments to this Schedule 13D, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary fully to all intents and purposes as he or it might or could do in person, thereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof. ValueAct Capital Master Fund L.P., by VA Partners I, LLC, its General Partner By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer VA Partners I, LLC By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer ValueAct Capital Management, L.P., by ValueAct Capital Management, LLC its General Partner By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer ValueAct Capital Management, LLC By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 11 of 12 ----------------------------------------------------------------------------- ValueAct Holdings, L.P., by ValueAct Holdings GP, LLC, its General Partner By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer ValueAct Holdings GP, LLC By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer SCHEDULE 13D -------------------------- ------------------------- CUSIP NO. 01973R101 Page 12 of 12 ----------------------------------------------------------------------------- Exhibit 1 JOINT FILING UNDERTAKING The undersigned parties hereby agree that the Schedule 13D filed herewith (and any amendments thereto) relating to the Common Stock of Allison Transmission Holdings, Inc., is being filed jointly on behalf of each of them with the Securities and Exchange Commission pursuant to Section 13(d) of the Securities Exchange Act of 1934, as amended. ValueAct Capital Master Fund L.P., by VA Partners I, LLC, its General Partner By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer VA Partners I, LLC By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer ValueAct Capital Management, L.P., by ValueAct Capital Management, LLC its General Partner By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer ValueAct Capital Management, LLC By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer ValueAct Holdings, L.P., by ValueAct Holdings GP, LLC, its General Partner By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer ValueAct Holdings GP, LLC By: /s/ Bradley E. Singer -------------------------------------- Dated: November 21, 2016 Bradley E. Singer, Chief Operating Officer