X0306 4 2020-03-08 0 0001093557 DEXCOM INC DXCM 0001286858 SAYER KEVIN R 6340 SEQUENCE DRIVE SAN DIEGO CA 92121 1 1 0 0 President, CEO and Chairman Common Stock 2020-03-08 4 A 0 25453 0.001 A 216390 D Common Stock 2020-03-09 4 S 0 254 261.6299 D 216136 D Common Stock 2020-03-09 4 S 0 250 262.0 D 215886 D Common Stock 2020-03-09 4 S 0 250 263.15 D 215636 D Common Stock 2020-03-09 4 S 0 150 264.7167 D 215486 D Common Stock 2020-03-09 4 S 0 1152 267.2062 D 214334 D Common Stock 2020-03-09 4 S 0 1098 268.0123 D 213236 D Common Stock 2020-03-09 4 S 0 250 269.0 D 212986 D Common Stock 2020-03-09 4 S 0 200 271.46 D 212786 D Common Stock 2020-03-09 4 S 0 2276 272.5141 D 210510 D Common Stock 2020-03-09 4 S 0 120 273.0542 D 210390 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 76,187 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 23,886 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 26,848 of which were granted on March 8, 2018 and shall vest through March 8, 2021. On May 15, 2019, Mr. Sayer adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Sayer. The shares set forth above were sold pursuant to the 10b5-1 Plan. This transaction was executed in multiple trades at prices ranging from $261.00 to $261.80. The price 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 transactions were effected. This transaction was executed in multiple trades at prices ranging from $264.29 to $264.93. The price 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 transactions were effected. This transaction was executed in multiple trades at prices ranging from $266.71 to $267.66. The price 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 transactions were effected. This transaction was executed in multiple trades at prices ranging from $267.99 to $268.11. The price 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 transactions were effected. This transaction was executed in multiple trades at prices ranging from $271.00 to $271.99. The price 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 transactions were effected. This transaction was executed in multiple trades at prices ranging from $272.00 to $272.99. The price 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 transactions were effected. This transaction was executed in multiple trades at prices ranging from $273.025 to $273.06. The price 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 transactions were effected. By: Jereme Sylvain For: Kevin R Sayer 2020-03-10