TDG Transdigm Group Incorporated

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                                                                                   
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940                       

1. Name and Address of Reporting Person * SMALL ROBERT J	2. Issuer Name and Ticker or Trading Symbol TransDigm Group INC [ TDG ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director                    _____ 10% Owner _____ Officer (give title below)    _____ Other (specify below)
(Last)          (First)          (Middle) C/O BERKSHIRE PARTNERS, 200 CLARENDON STREET, 35TH FLOOR	3. Date of Earliest Transaction (MM/DD/YYYY) 10/19/2020
(Street) BOSTON, MA 02116 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. 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	10/19/2020		A		76	A	$491.32 (1)	31024	D
Common Stock								2466278	I (2)	By Berkshire Entities
Common Stock								165688	I (3)	By Stockbridge Partners LLC
Common Stock								20301	I (4)	By Family Trust
Common Stock								50000	I (5)	By Trust

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. 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		7. Title and Amount of Securities Underlying Derivative Security (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

Explanation of Responses:
(1)	Receipt of stock in lieu of payment of semi-annual director fee, based on fair market value in accordance with the Director Share Plan.
(2)	Represents shares held directly or indirectly by Berkshire Fund VIII, L.P. ("VIII"), Berkshire Fund VIII-A, L.P. ("VIII-A"), Berkshire Fund IX, L.P. ("IX"), Berkshire Fund IX-A, L.P. ("IX-A"), Berkshire Investors III LLC ("Investors III"), Berkshire Investors IV LLC ("Investors IV"), Stockbridge Fund, L.P. ("SF") and Stockbridge Absolute Return Fund, L.P. ("SARF") (collectively, the "Berkshire Entities"). Berkshire Partners Holdings LLC ("BPH") is the general partner of BPSP, L.P. ("BPSP"), which is the managing member of each of Berkshire Partners, LLC, the registered investment adviser to VIII, VIII-A, IX, IX-A, Investors III and Investors IV ("BP"), and SP, the registered investment adviser to SF and SARF. Eighth Berkshire Associates LLC ("8BA") is the general partner of each of VIII and VII-A. Ninth Berkshire Associates LLC ("9BA") is the general partner of each of IX and IX-A. Stockbridge Associates LLC ("SA") is the general partner of each of SF and SARF.
(3)	Represents shares held by SP on behalf of a managed account over which it has shared voting and sole dispositive power.
(4)	Represents shares of Common Stock beneficially owned by certain family trusts. The Reporting Person is a trustee and the Reporting Person's immediate family members are beneficiaries of such family trusts
(5)	Represents shares of Common Stock beneficially owned by a trust. The Reporting Person is a trustee and the Reporting Person's immediate family members are beneficiaries of such trust.

Remarks: Indirect ownership of shares held by the Berkshire Entities and SP is included because the Reporting Person is a managing member of SP and of BPH, BPSP, BP, SP, 8BA, 9BA, SA, Investors III and Investors IV (see footnotes 1 and 2). As such, the Reporting Person may be deemed to share voting and dispositive power with respect to the shares of the Issuer's stock held by the Berkshire Entities and SP. However, the Reporting Person disclaims beneficial ownership of such shares, expect to the extent, if any, of his pecuniary interest therein, and inclusion of the shares in this report shall not be deemed an admission of beneficial ownership of the securities for purposes of Section 16 or any other purpose.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
SMALL ROBERT J C/O BERKSHIRE PARTNERS 200 CLARENDON STREET, 35TH FLOOR BOSTON, MA 02116	X

Signatures
Halle Fine Terrion as attorney-in-fact for Robert Small		10/20/2020
**Signature of Reporting Person		Date