X0609 4 2026-09-14 0 0001093557 DEXCOM INC DXCM 0001238485 AUGUSTINOS NICHOLAS false 6340 SEQUENCE DRIVE SAN DIEGO CA 92121 1 0 0 0 1 Common Stock 2026-09-14 4 S 0 1550 84.02 D 35832 I by Trust Common Stock 2026-09-15 4 S 0 6539 84.04 D 29293 I by Trust Common Stock 5575 D On June 10, 2026, Mr. Augustinos adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Augustinos. The shares set forth above were sold pursuant to the 10b5-1 Plan. Shares are held by the Kirschner/Augustinos Revocable Trust, with respect to which the Reporting Person is a trustee. Represents unvested restricted stock units which were granted on May 28, 2026 and will vest on the earlier of the one year anniversary of the grant date or the date of DexCom, Inc.'s 2027 Annual Meeting of Stockholders. /s/ Jereme M. Sylvain, as Attorney-in-Fact for Nicholas Augustinos 2026-09-16