Sec Form 4 Filing - Stein Kevin M @ TransDigm Group INC - 2025-02-12

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 Stein Kevin M 2. Issuer Name and Ticker or Trading Symbol TransDigm Group INC [ TDG] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) President & CEO (Last) (First) (Middle) 1350 EUCLID AVE, SUITE 1600 3. Date of Earliest Transaction (MM/DD/YY) 02/12/2025 (Street) CLEVELAND, OH44115 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ 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 02/12/2025 M 20,000 A $ 195.88 ( 1 ) 28,158 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 190 D $ 1,335.71 27,968 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 90 D $ 1,337.8253 ( 2 ) 27,878 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 230 D $ 1,339.293 ( 3 ) 27,648 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 55 D $ 1,340.73 27,593 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 118 D $ 1,342.1178 ( 4 ) 27,475 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 235 D $ 1,343.3455 ( 5 ) 27,240 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 226 D $ 1,344.8458 ( 6 ) 27,014 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 690 D $ 1,346.296 ( 7 ) 26,324 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 1,359 D $ 1,347.5928 ( 8 ) 24,965 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 3,241 D $ 1,348.5515 ( 9 ) 21,724 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 1,692 D $ 1,349.6089 ( 10 ) 20,032 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 296 D $ 1,350.2603 ( 11 ) 19,736 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 708 D $ 1,352.1761 ( 12 ) 19,028 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 1,147 D $ 1,353.8203 ( 13 ) 17,881 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 840 D $ 1,354.9505 ( 14 ) 17,041 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 840 D $ 1,355.8471 ( 15 ) 16,201 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 1,069 D $ 1,357.4363 ( 16 ) 15,132 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 482 D $ 1,358.028 ( 17 ) 14,650 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 1,321 D $ 1,359.2672 ( 18 ) 13,329 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 598 D $ 1,360.3688 ( 19 ) 12,731 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 1,149 D $ 1,361.4017 ( 20 ) 11,582 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 1,919 D $ 1,362.1485 ( 21 ) 9,663 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 477 D $ 1,363.198 ( 22 ) 9,186 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 431 D $ 1,364.1463 ( 23 ) 8,755 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 479 D $ 1,365.1225 ( 24 ) 8,276 I Fortuna Trust dated June 1, 2018 Common Stock 02/12/2025 S 118 D $ 1,366.1051 ( 25 ) 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 (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) (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 $ 195.88 ( 1 ) 02/12/2025 M 20,000 09/30/2018 04/25/2028 Common Stock 20,000 $ 0 113,500 I Fortuna Trust dated June 1, 2018

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Stein Kevin M 1350 EUCLID AVE SUITE 1600 CLEVELAND, OH44115 President & CEO Signatures /s/ Gabrielle Feuer as attorney-in-fact 02/13/2025 Signature of Reporting Person Date

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 $1,337.26 - $1,338.22. 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 $1,339.2050 - $1,339.34. 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 $1,341.9950 - $1,342.80. 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. ( 5 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,343.28 - $1,343.47. 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. ( 6 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,344.43 - $1,345.1950. 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. ( 7 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,346.06 - $1,346.8150. 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. ( 8 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,347.06 - $1,348.01. 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. ( 9 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,348.10 - $1,349.0950. 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. ( 10 )Price reported constitutes the average weighted price of shares sold. Sha res were sold at varying prices in the range of $1,349.1850 - $1,350.16. 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. ( 11 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,350.1850 - $1,350.4650. 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. ( 12 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,351.6950 - $1,352.6750. 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. ( 13 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,353.33 - $1,354.14. 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. ( 14 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,354.3350 - $1,355.33. 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. ( 15 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,355.47 - $1,356.17. 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. ( 16 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,356.8350 - $1,357.8250. 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. ( 17 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,357.8550 - $1,358.83. 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. ( 18 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,358.8750 - $1,359.79. 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. ( 19 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,359.88 - $1,360.8550. 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. ( 20 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,360.89 - $1,361.88. 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. ( 21 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,361.8950 - $1,362.4350. 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. ( 22 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,362.92 - $1363.72. 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. ( 23 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,363.92 - $1,364.81. 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. ( 24 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,365.02 - $1,365.46. 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. ( 25 )Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,366.0450 - $1,366.19. 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.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* 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).

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