X0306 4 2020-03-11 0 0001093557 DEXCOM INC DXCM 0001692785 Murphy Patrick Michael 6340 SEQUENCE DRIVE SAN DIEGO CA 92121 0 1 0 0 * Common Stock 2020-03-11 4 S 0 54 246.0614 D 34704 D Common Stock 2020-03-11 4 S 0 107 250.2 D 34597 D Common Stock 2020-03-11 4 S 0 3921 265.426 D 30676 D Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of RSUs. This sale is mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and does not represent a discretionary trade by the reporting person. This transaction was executed in multiple trades at prices ranging from $246.00 to $246.0626. 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. Included in this number are 22,225 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,809 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 5,605 of which were granted on March 8, 2018 and shall vest through March 8, 2021. This transaction was executed in multiple trades at prices ranging from $250.09 to $250.72. 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. *Executive Vice President, Chief Legal Officer and Chief Compliance Officer By: Jereme Sylvain For: Patrick M Murphy 2020-03-13