144 0001797971 XXXXXXXX LIVE 0001093557 DEXCOM, INC. 000-51222 6340 Sequence Drive San Diego CA 92121 (858) 200-0200 SADIE STERN Officer Common Morgan Stanley Smith Barney LLC Executive Financial Services

1 New York Plaza 8th Floor New York NY 10004

1466 117280.00 392155265 09/04/2025 NASDAQ Common 12/15/2023 Restricted Stock ISSUER N 978 12/15/2023 Not Applicable Common 11/19/2023 Restricted Stock ISSUER N 488 11/19/2023 Not Applicable N SADIE STERN

6340 Sequence Drive San Diego CA 92121

Common 07/28/2025 1466 130459.34 SADIE STERN

6340 Sequence Drive San Diego CA 92121

Common 06/26/2025 1466 124697.96 09/04/2025 02/20/2025 /s/ Sadie Stern