X0306 4 2020-03-08 0 0001093557 DEXCOM INC DXCM 0001612451 Blackford Quentin S. 6340 SEQUENCE DRIVE SAN DIEGO CA 92121 0 1 0 0 Chief Operating Officer & CFO Common Stock 2020-03-08 4 A 0 12727 0.001 A 82655 D Common Stock 2020-03-09 4 S 0 891 261.0 D 81764 D Represents a grant of restricted stock units that are exempt from Section 16 b-3 and are subject to vesting in three equal annual installments from the date of grant. Share units represent a contingent right to receive one share of DexCom, Inc. Common Stock. Included in this number are 69,029 unvested restricted stock units, 12,727 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 12,288 of which were granted on March 8, 2019 and shall vest through March 8, 2022, 12,834 of which were granted on March 8, 2018 and shall vest through March 8, 2021 and 31,180 of which were granted on September 7, 2017 and shall vest through September 7, 2021. On December 9, 2019, Mr. Blackford adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Blackford. The shares set forth above were sold pursuant to the 10b5-1 Plan. By: Jereme Sylvain For: Quentin S Blackford 2020-03-10