X0508 4 2024-08-15 0000820313 AMPHENOL CORP /DE/ APH 0001662750 Doherty William J C/O AMPHENOL TCS 200 INNOVATIVE WAY, STE 201 NASHUA NH 03062 1 President, CS Division 0 Class A Common Stock 2024-08-15 4 M 0 300000 22.3725 A 300000 D Class A Common Stock 2024-08-15 4 S 0 300000 65.8286 D 0 D Stock Option 22.3725 2024-08-15 4 M 0 300000 0 D 2020-05-23 2029-05-23 Class A Common Stock 300000 136000 D The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. This transaction was executed in multiple trades ranging from $65.6600 to $65.9800. All information in this Form 4 reflects the impact of the issuer's 2-for-1 stock split effected on June 11, 2024. /s/ Lance E. D'Amico, POA 2024-08-16