[Form 4] TransDigm Group INC Insider Trading Activity

Rhea-AI Filing Summary

TransDigm Group (TDG) director Kevin Stein, reporting through the Fortuna Trust dated June 1, 2018, disclosed an option exercise and related share sales. On 11/20/2025, the trust exercised a stock option for 1,104 shares of common stock at an exercise price of $105.88 per share, originally granted in 2018 and expiring in 2028. The same day, the trust sold 655 shares at an average $1,360.3298, 400 shares at an average $1,361.5239, and 49 shares at an average $1,363.2231, with each sale reported as an average weighted price over a narrow range. After these transactions, the trust beneficially owned 8,158 shares of TransDigm common stock and 64,505 stock options, all reported as indirect ownership through the trust.

Insider Trade Summary

Net Seller: 1,104 shares ($1,502,424)

Net Sell 5 txns

Insider Stein Kevin M

Role Director

Sold 1,104 shs ($1.50M)

Type	Security	Shares	Price	Value
Exercise	Stock Option	1,104	$0.00	--
Exercise	Common Stock	1,104	$105.88	$117K
Sale	Common Stock	655	$1,360.3298	$891K
Sale	Common Stock	400	$1,361.5239	$545K
Sale	Common Stock	49	$1,363.2231	$67K

Holdings After Transaction: Stock Option — 64,505 shares (Indirect, Fortuna Trust dated June 1, 2018); Common Stock — 9,262 shares (Indirect, Fortuna Trust dated June 1, 2018)

Footnotes (1)

1. The exercise price has been adjusted for dividends declared since August 1, 2022. Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,360.0000- $1,360.9999. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price. Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,361.1400- $1,362.1399. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price. Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,363.0000- $1,363.9999. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

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
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

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

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Stein Kevin M

(Last) (First) (Middle)

1350 EUCLID AVE

SUITE 1600

(Street)

CLEVELAND OH 44115

(City) (State) (Zip)

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)

3. Date of Earliest Transaction (Month/Day/Year)
11/20/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

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. 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	11/20/2025		M		1,104	A	$105.88(1)	9,262	I	Fortuna Trust dated June 1, 2018
Common Stock	11/20/2025		S		655	D	$1,360.3298(2)	8,607	I	Fortuna Trust dated June 1, 2018
Common Stock	11/20/2025		S		400	D	$1,361.5239(3)	8,207	I	Fortuna Trust dated June 1, 2018
Common Stock	11/20/2025		S		49	D	$1,363.2231(4)	8,158	I	Fortuna Trust dated June 1, 2018

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 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: 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
Stock Option	$105.88	11/20/2025		M			1,104	09/30/2018	04/25/2028	Common Stock	1,104	$0	64,505	I	Fortuna Trust dated June 1, 2018

Explanation of Responses:

1. The exercise price has been adjusted for dividends declared since August 1, 2022.

2. Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,360.0000- $1,360.9999. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.

3. Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,361.1400- $1,362.1399. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.

4. Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,363.0000- $1,363.9999. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.

	/s/ Lisa Tortora French as attorney in-fact for Kevin Stein	11/21/2025
	** Signature of Reporting Person	Date
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