=== SEC Form 4 — Statement of Changes in Beneficial Ownership ===
Document Type: 4
Period of Report: 2026-09-15
10b5-1 Pre-arranged Plan: Yes
--- Issuer ---
Name: TransDigm Group INC (TDG)
CIK: 0001260221
--- Reporting Owner ---
Name: Reiss Joel
CIK: 0001656109
Role: Officer (Co-Chief Operating Officer)
--- Non-Derivative Transactions ---
[Transaction #1]
Security: Common Stock
Date: 2026-09-15 | Code: M (Exercise of derivative)
Shares: +3,900 | Price: $284.97
Total Value: $1,111,383.00
Shares Owned After: 7,500 | Ownership: D (Direct)
[Transaction #2]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -310 | Price: $1,082.96
Total Value: $335,718.81
Shares Owned After: 7,190 | Ownership: D (Direct)
Footnotes:
[F1] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,082.3500 - $1,083.2700. 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.
[Transaction #3]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -170 | Price: $1,083.67
Total Value: $184,224.39
Shares Owned After: 7,020 | Ownership: D (Direct)
Footnotes:
[F2] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,083.3700 - $1,084.2700. 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.
[Transaction #4]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -240 | Price: $1,084.87
Total Value: $260,368.70
Shares Owned After: 6,780 | Ownership: D (Direct)
Footnotes:
[F3] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,084.6500 - $1,085.2700. 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.
[Transaction #5]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -110 | Price: $1,086.27
Total Value: $119,490.00
Shares Owned After: 6,670 | Ownership: D (Direct)
Footnotes:
[F4] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,085.7600 - $1,086.5700. 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.
[Transaction #6]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -120 | Price: $1,087.49
Total Value: $130,498.70
Shares Owned After: 6,550 | Ownership: D (Direct)
Footnotes:
[F5] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,087.0000 - $1,087.9200. 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.
[Transaction #7]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -10 | Price: $1,088.06
Total Value: $10,880.60
Shares Owned After: 6,540 | Ownership: D (Direct)
[Transaction #8]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -70 | Price: $1,090.06
Total Value: $76,304.00
Shares Owned After: 6,470 | Ownership: D (Direct)
Footnotes:
[F6] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,089.5400 - $1,090.3600. 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.
[Transaction #9]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -100 | Price: $1,091.00
Total Value: $109,100.18
Shares Owned After: 6,370 | Ownership: D (Direct)
Footnotes:
[F7] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,090.5800 - $1,091.4500. 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.
[Transaction #10]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -170 | Price: $1,092.13
Total Value: $185,661.83
Shares Owned After: 6,200 | Ownership: D (Direct)
Footnotes:
[F8] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,091.5800 - $1,092.5700. 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.
[Transaction #11]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -282 | Price: $1,093.10
Total Value: $308,255.22
Shares Owned After: 5,918 | Ownership: D (Direct)
Footnotes:
[F9] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,092.5800 - $1,093.5700. 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.
[Transaction #12]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -383 | Price: $1,094.06
Total Value: $419,025.17
Shares Owned After: 5,535 | Ownership: D (Direct)
Footnotes:
[F10] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,093.6200 - $1,094.5600. 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.
[Transaction #13]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -225 | Price: $1,095.11
Total Value: $246,399.28
Shares Owned After: 5,310 | Ownership: D (Direct)
Footnotes:
[F11] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,094.6300 - $1,095.5700. 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.
[Transaction #14]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -196 | Price: $1,096.17
Total Value: $214,849.03
Shares Owned After: 5,114 | Ownership: D (Direct)
Footnotes:
[F12] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,095.7000 - $1,096.6900. 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.
[Transaction #15]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -294 | Price: $1,097.26
Total Value: $322,595.41
Shares Owned After: 4,820 | Ownership: D (Direct)
Footnotes:
[F13] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,096.7000 - $1,097.6900. 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.
[Transaction #16]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -150 | Price: $1,098.41
Total Value: $164,761.05
Shares Owned After: 4,670 | Ownership: D (Direct)
Footnotes:
[F14] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,097.7200 - $1,098.7100. 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.
[Transaction #17]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -90 | Price: $1,099.14
Total Value: $98,922.86
Shares Owned After: 4,580 | Ownership: D (Direct)
Footnotes:
[F15] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,098.7700 - $1,099.6500. 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.
[Transaction #18]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -60 | Price: $1,100.41
Total Value: $66,024.33
Shares Owned After: 4,520 | Ownership: D (Direct)
Footnotes:
[F16] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,099.9300 - $1,100.7000. 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.
[Transaction #19]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -166 | Price: $1,101.52
Total Value: $182,853.03
Shares Owned After: 4,354 | Ownership: D (Direct)
Footnotes:
[F17] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,100.9400 - $1,101.9200. 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.
[Transaction #20]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -274 | Price: $1,102.49
Total Value: $302,082.07
Shares Owned After: 4,080 | Ownership: D (Direct)
Footnotes:
[F18] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,102.0000 - $1,102.9800. 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.
[Transaction #21]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -210 | Price: $1,103.44
Total Value: $231,721.92
Shares Owned After: 3,870 | Ownership: D (Direct)
Footnotes:
[F19] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,103.0100 - $1,103.8850. 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.
[Transaction #22]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -125 | Price: $1,104.58
Total Value: $138,072.15
Shares Owned After: 3,745 | Ownership: D (Direct)
Footnotes:
[F20] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,104.0300 - $1,105.0100. 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.
[Transaction #23]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -5 | Price: $1,105.28
Total Value: $5,526.42
Shares Owned After: 3,740 | Ownership: D (Direct)
Footnotes:
[F21] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,105.2400 - $1,105.4600. 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.
[Transaction #24]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -40 | Price: $1,106.69
Total Value: $44,267.49
Shares Owned After: 3,700 | Ownership: D (Direct)
Footnotes:
[F22] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,106.3200 - $1,106.8900. 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.
[Transaction #25]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -30 | Price: $1,108.34
Total Value: $33,250.30
Shares Owned After: 3,670 | Ownership: D (Direct)
Footnotes:
[F23] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,108.2300 - $1,108.4000. 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.
[Transaction #26]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -30 | Price: $1,112.38
Total Value: $33,371.30
Shares Owned After: 3,640 | Ownership: D (Direct)
Footnotes:
[F24] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,112.3400 - $1,112.4500. 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.
[Transaction #27]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -20 | Price: $1,113.37
Total Value: $22,267.40
Shares Owned After: 3,620 | Ownership: D (Direct)
[Transaction #28]
Security: Common Stock
Date: 2026-09-15 | Code: S (Open market sale)
Shares: -20 | Price: $1,118.99
Total Value: $22,379.90
Shares Owned After: 3,600 | Ownership: D (Direct)
Footnotes:
[F25] Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,118.9700 - $1,119.0200. 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.
--- Derivative Transactions ---
[Transaction #1]
Security: Stock Option
Date: 2026-09-15 | Code: M (Exercise of derivative)
Shares: -3,900 | Price: $0.00
Exercise Price: $284.97
Exercisable: N/A | Expires: 2027-11-08
Shares Owned After: 4,100 | Ownership: D (Direct)
--- Footnotes (Complete Index) ---
F1: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,082.3500 - $1,083.2700. 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.
F10: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,093.6200 - $1,094.5600. 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.
F11: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,094.6300 - $1,095.5700. 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.
F12: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,095.7000 - $1,096.6900. 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.
F13: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,096.7000 - $1,097.6900. 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.
F14: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,097.7200 - $1,098.7100. 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.
F15: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,098.7700 - $1,099.6500. 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.
F16: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,099.9300 - $1,100.7000. 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.
F17: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,100.9400 - $1,101.9200. 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.
F18: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,102.0000 - $1,102.9800. 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.
F19: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,103.0100 - $1,103.8850. 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.
F2: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,083.3700 - $1,084.2700. 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.
F20: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,104.0300 - $1,105.0100. 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.
F21: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,105.2400 - $1,105.4600. 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.
F22: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,106.3200 - $1,106.8900. 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.
F23: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,108.2300 - $1,108.4000. 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.
F24: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,112.3400 - $1,112.4500. 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.
F25: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,118.9700 - $1,119.0200. 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.
F3: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,084.6500 - $1,085.2700. 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.
F4: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,085.7600 - $1,086.5700. 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.
F5: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,087.0000 - $1,087.9200. 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.
F6: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,089.5400 - $1,090.3600. 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.
F7: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,090.5800 - $1,091.4500. 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.
F8: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,091.5800 - $1,092.5700. 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.
F9: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $1,092.5800 - $1,093.5700. 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.
--- Signature ---
/s/ /s/ Rachel L. Quinlan as attorney in fact for Joel Reiss (2026-09-16)
