Sec Form 4 Filing - Makaira Partners LLC @ Wesco Aircraft Holdings, Inc - 2019-08-16

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 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 Makaira Partners LLC 2. Issuer Name and Ticker or Trading Symbol Wesco Aircraft Holdings, Inc [ WAIR] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner _____ Officer (give title below) X __ Other (specify below) Former 10% Owner (Last) (First) (Middle) 7776 IVANHOE AVENUE #250, 3. Date of Earliest Transaction (MM/DD/YY) 08/16/2019 (Street) LA JOLLA, CA92037 4. If Amendment, Date Original Filed (MM/DD/YY) 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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 08/16/2019 J( 1 ) 3,859,178 D 6,958,250 I See footnote ( 2 ) Common Stock 29,859 I See footnote ( 3 ) Common Stock 35,533 I See footnote ( 4 ) Common Stock 49,200 I See footnote ( 5 )

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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 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) (Inst r. 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 Makaira Partners LLC 7776 IVANHOE AVENUE #250 LA JOLLA, CA92037 Former 10% Owner Bancroft Thomas C/O WESCO AIRCRAFT HOLDINGS, INC. 24911 AVENUE STANFORD VALENCIA, CA91355 X Signatures Makaira Partners LLC, by: /s/ Adam Garcia, Chief Financial Officerand Chief Compliance Officer 08/20/2019/s/ Thomas Bancroft 08/20/2019 08/20/2019 Signature of Reporting Person Date

Explanation of Responses:

( 1 )On August 16, 2019, Makaira Partners LLC ceased to have authority over (and thus ceased to have beneficial ownership for purposes of Sections 13 and 16 of the Exchange Act of) 3,859,178 shares of Common Stock that were held in a client separate account managed by Makaira Partners LLC as investment adviser. ( 2 )By Makaira Partners LLC. Thomas Bancroft is the Managing Member, Portfolio Manager and Chief Investment Officer of Makaira Partners LLC. Each of Makaira Partners LLC and Mr. Bancroft disclaims beneficial ownership for purposes of Section 16 of the Exchange Act of all securities reported herein, except to the extent of its or his pecuniary interest therein. ( 3 )By Mr. Bancroft. Mr. Bancroft is the Managing Member, Portfolio Manager and Chief Investment Officer of Makaira Partners LLC. Makaira Partners LLC disclaims beneficial ownership of such shares and disclaims membership in a group with Mr. Bancroft. ( 4 )By family members of Mr. Bancroft. Mr. Bancroft disclaims beneficial ownership for purposes of Section 16 of the Exchange Act of all securities reported herein, except to the extent of his pecuniary interest therein. Makaira Partners LLC disclaims beneficial ownership of such shares and disclaims membership in a group with Mr. Bancroft. ( 5 )By Mr. Bancroft's IRA. Makaira Partners LLC disclaims beneficial ownership of such shares and disclaims membership in a group with Mr. Bancroft.

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