DXCM

SEC source: 0001093557-20-000331 · edgardoc.xml · nonDerivative · entry 3

Pacelli Steven Robert · CIK 0001359098 · EVP Strategy and Corporate Dev

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 60,101

F1 · shares: On June 15, 2020, Mr. Pacelli adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Pacelli. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F5 · price: This transaction was executed in multiple trades at prices ranging from $359.73 to $360.25. 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 issurer full information regarding the number of shares and prices at which the transactions were effected.

F3 · balance_after: Included in this number are 22,722 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,494 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000331 · edgardoc.xml · nonDerivative · entry 2

Pacelli Steven Robert · CIK 0001359098 · EVP Strategy and Corporate Dev

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 60,311

F1 · shares: On June 15, 2020, Mr. Pacelli adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Pacelli. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F4 · price: This transaction was executed in multiple trades at prices ranging from $358.59 to $359.25. 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.

F3 · balance_after: Included in this number are 22,722 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,494 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000331 · edgardoc.xml · nonDerivative · entry 1

Pacelli Steven Robert · CIK 0001359098 · EVP Strategy and Corporate Dev

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 60,603

F1 · shares: On June 15, 2020, Mr. Pacelli adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Pacelli. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2 · price: This transaction was executed in multiple trades at prices ranging from $357.43 to $358.36. 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.

F3 · balance_after: Included in this number are 22,722 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,494 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000330 · edgardoc.xml · nonDerivative · entry 7

DOUBLEDAY RICHARD · CIK 0001466545 · EVP Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 9,983

F1 · shares: On June 15, 2020, Mr. Doubleday adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Doubleday. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F9 · price: This transaction was executed in multiple trades at prices ranging from $363.94 to $364.24. 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.

F3 · ownership.nature: Shares are held by the Doubleday Living Trust U/A/D 5/26/2015, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000330 · edgardoc.xml · nonDerivative · entry 6

DOUBLEDAY RICHARD · CIK 0001466545 · EVP Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 10,063

F1 · shares: On June 15, 2020, Mr. Doubleday adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Doubleday. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F8 · price: This transaction was executed in multiple trades at prices ranging from $362.50 to $363.00. 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.

F3 · ownership.nature: Shares are held by the Doubleday Living Trust U/A/D 5/26/2015, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000330 · edgardoc.xml · nonDerivative · entry 5

DOUBLEDAY RICHARD · CIK 0001466545 · EVP Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 10,123

F1 · shares: On June 15, 2020, Mr. Doubleday adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Doubleday. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F7 · price: This transaction was executed in multiple trades at prices ranging from $361.08 to $361.90. 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.

F3 · ownership.nature: Shares are held by the Doubleday Living Trust U/A/D 5/26/2015, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000330 · edgardoc.xml · nonDerivative · entry 4

DOUBLEDAY RICHARD · CIK 0001466545 · EVP Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 10,303

F1 · shares: On June 15, 2020, Mr. Doubleday adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Doubleday. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F6 · price: This transaction was executed in multiple trades at prices ranging from $360.00 to $360.93. 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.

F3 · ownership.nature: Shares are held by the Doubleday Living Trust U/A/D 5/26/2015, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000330 · edgardoc.xml · nonDerivative · entry 3

DOUBLEDAY RICHARD · CIK 0001466545 · EVP Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 10,426

F1 · shares: On June 15, 2020, Mr. Doubleday adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Doubleday. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F5 · price: This transaction was executed in multiple trades at prices ranging from $359.00 to $359.99. 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.

F3 · ownership.nature: Shares are held by the Doubleday Living Trust U/A/D 5/26/2015, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000330 · edgardoc.xml · nonDerivative · entry 2

DOUBLEDAY RICHARD · CIK 0001466545 · EVP Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 10,708

F1 · shares: On June 15, 2020, Mr. Doubleday adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Doubleday. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F4 · price: This transaction was executed in multiple trades at prices ranging from $358.000 to $358.925. 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.

F3 · ownership.nature: Shares are held by the Doubleday Living Trust U/A/D 5/26/2015, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000330 · edgardoc.xml · nonDerivative · entry 1

DOUBLEDAY RICHARD · CIK 0001466545 · EVP Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 10,973

F1 · shares: On June 15, 2020, Mr. Doubleday adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Doubleday. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2 · price: This transaction was executed in multiple trades at prices ranging from $357.00 to $357.50. 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.

F3 · ownership.nature: Shares are held by the Doubleday Living Trust U/A/D 5/26/2015, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000327 · edgardoc.xml · nonDerivative · entry 3

AUGUSTINOS NICHOLAS · CIK 0001238485 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 12,592

F1 · shares: On March 4, 2020, Mr. Augustinos adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Augustinos. The sale of shares set forth above were pursuant to the 10b5-1 Plan.

F2 · ownership.nature: Shares are held by the Kirschner/Augustinos Revocable Trust, of which the reporting person is trustee.

SEC source: 0001093557-20-000327 · edgardoc.xml · nonDerivative · entry 2

AUGUSTINOS NICHOLAS · CIK 0001238485 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 13,217

F1 · shares: On March 4, 2020, Mr. Augustinos adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Augustinos. The sale of shares set forth above were pursuant to the 10b5-1 Plan.

F2 · ownership.nature: Shares are held by the Kirschner/Augustinos Revocable Trust, of which the reporting person is trustee.

SEC source: 0001093557-20-000327 · edgardoc.xml · nonDerivative · entry 1

AUGUSTINOS NICHOLAS · CIK 0001238485 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 13,242

F1 · shares: On March 4, 2020, Mr. Augustinos adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Augustinos. The sale of shares set forth above were pursuant to the 10b5-1 Plan.

F2 · ownership.nature: Shares are held by the Kirschner/Augustinos Revocable Trust, of which the reporting person is trustee.

SEC source: 0001093557-20-000325 · edgardoc.xml · nonDerivative · entry 1

Heller Bridgette P · CIK 0001485616 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,448

F1 · shares: On September 15, 2020, Ms. Heller adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Ms. Heller. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2 · balance_after: Included in this number are 2,811 unvested restricted stock units, 787 of which were granted on May 22, 2020 and shall vest on the earlier of the one year anniversary of the grant or the date of DexCom Inc's 2021 Annual Meeting and 2,024 of which were granted on September 13, 2019 and shall vest through September 13, 2022.

SEC source: 0001093557-20-000322 · edgardoc.xml · nonDerivative · entry 1

Murphy Patrick Michael · CIK 0001692785 · EVP, Chief Legal Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 19,578

F1 · shares: On August 28, 2020, Mr. Murphy adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Murphy. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2 · balance_after: Included in this number are 17,471 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 5,857 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 2,803 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000323 · edgardoc.xml · nonDerivative · entry 5

SAYER KEVIN R · CIK 0001286858 · Director · Chairman, CEO & President

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 115,514

F1 · shares: On July 31, 2020, 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.

F7 · price: This transaction was executed in multiple trades at prices ranging from $324.13 to $324.51. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000323 · edgardoc.xml · nonDerivative · entry 4

SAYER KEVIN R · CIK 0001286858 · Director · Chairman, CEO & President

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 116,774

F1 · shares: On July 31, 2020, 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.

F6 · price: This transaction was executed in multiple trades at prices ranging from $322.99 to $323.92. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000323 · edgardoc.xml · nonDerivative · entry 3

SAYER KEVIN R · CIK 0001286858 · Director · Chairman, CEO & President

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 119,893

F1 · shares: On July 31, 2020, 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.

F5 · price: This transaction was executed in multiple trades at prices ranging from $321.88 to $322.76. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000323 · edgardoc.xml · nonDerivative · entry 2

SAYER KEVIN R · CIK 0001286858 · Director · Chairman, CEO & President

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 123,863

F1 · shares: On July 31, 2020, 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.

F4 · price: This transaction was executed in multiple trades at prices ranging from $320.61 to $321.56. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000323 · edgardoc.xml · nonDerivative · entry 1

SAYER KEVIN R · CIK 0001286858 · Director · Chairman, CEO & President

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 127,190

F1 · shares: On July 31, 2020, 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.

F2 · price: This transaction was executed in multiple trades at prices ranging from $319.29 to $320.13. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000319 · edgardoc.xml · nonDerivative · entry 1

Sylvain Jereme M · CIK 0001681267 · SVP, Finance & CAO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 11,300

F1 · shares: On May 26, 2020, Mr. Sylvain adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Sylvain. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2 · balance_after: Included in this number are 9,169 unvested restricted stock units, 5,483 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 2,412 of which were granted on March 8, 2019 and shall vest through March 8, 2022 and 1,274 of which were granted on November 8, 2018 and shall vest through November 8, 2021.

SEC source: 0001093557-20-000318 · edgardoc.xml · nonDerivative · entry 1

Pacelli Steven Robert · CIK 0001359098 · EVP Strategy and Corporate Dev

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 60,860

F1 · shares: On June 15, 2020, Mr. Pacelli adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Pacelli. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2 · balance_after: Included in this number are 22,722 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,494 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000317 · edgardoc.xml · nonDerivative · entry 1

DOUBLEDAY RICHARD · CIK 0001466545 · EVP Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 11,093

F1 · shares: On June 15, 2020, Mr. Doubleday adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Doubleday. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2 · ownership.nature: Shares are held by the Doubleday Living Trust U/A/D 5/26/2015, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000313 · wf-form4a_160592173395043.xml · nonDerivative · entry 1

Stern Sadie · CIK 0001797971 · EVP Chief Human Resources Off

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,207

F1 · security: This amendment to Form 4 corrects the number of restricted stock units ("RSUs") granted and the date of grant as previously reported on Form 4 filed November 10, 2020. The correct date of grant for the RSUs is November 19, 2020 and the correct number of RSUs granted is 8,207.

F2 · shares: Represents a grant of RSUs that vest in four annual installments on November 19, 2021, November 19, 2022, November 19, 2023 and November 19, 2024. Share units represent a contingent right to receive one share of Dexcom, Inc. common stock upon settlement for no consideration.

F2 · balance_after: Represents a grant of RSUs that vest in four annual installments on November 19, 2021, November 19, 2022, November 19, 2023 and November 19, 2024. Share units represent a contingent right to receive one share of Dexcom, Inc. common stock upon settlement for no consideration.

SEC source: 0001093557-20-000310 · edgardoc.xml · nonDerivative · entry 1

Regan Barry J. · CIK 0001746313 · EVP Operations

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,207

F1 · shares: Represents a grant of RSUs that vest in four annual installments on November 19, 2021, November 19, 2022, November 19, 2023 and November 19, 2024. Share units represent a contingent right to receive one share of Dexcom, Inc. common stock upon settlement for no consideration.

F1 · balance_after: Represents a grant of RSUs that vest in four annual installments on November 19, 2021, November 19, 2022, November 19, 2023 and November 19, 2024. Share units represent a contingent right to receive one share of Dexcom, Inc. common stock upon settlement for no consideration.

SEC source: 0001093557-20-000306 · edgardoc.xml · nonDerivative · entry 5

FOLETTA MARK G · CIK 0001236389 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 13,202

F1 · shares: On June 6, 2020, Mr. Foletta adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Foletta. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F6 · price: This transaction was executed in multiple trades at prices ranging from $342.53 to $343.185. 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.

F3 · ownership.nature: Shares are held by the Mark G. and Mary E. Foletta, TTEE's for the Foletta Family Trust DTD 1/30/15, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000306 · edgardoc.xml · nonDerivative · entry 4

FOLETTA MARK G · CIK 0001236389 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 13,503

F1 · shares: On June 6, 2020, Mr. Foletta adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Foletta. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F5 · price: This transaction was executed in multiple trades at prices ranging from $341.37 to $342.295. 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.

F3 · ownership.nature: Shares are held by the Mark G. and Mary E. Foletta, TTEE's for the Foletta Family Trust DTD 1/30/15, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000306 · edgardoc.xml · nonDerivative · entry 3

FOLETTA MARK G · CIK 0001236389 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 13,931

F1 · shares: On June 6, 2020, Mr. Foletta adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Foletta. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F4 · price: This transaction was executed in multiple trades at prices ranging from $339.93 to $340.565. 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.

F3 · ownership.nature: Shares are held by the Mark G. and Mary E. Foletta, TTEE's for the Foletta Family Trust DTD 1/30/15, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000306 · edgardoc.xml · nonDerivative · entry 2

FOLETTA MARK G · CIK 0001236389 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 14,048

F1 · shares: On June 6, 2020, Mr. Foletta adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Foletta. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F3 · ownership.nature: Shares are held by the Mark G. and Mary E. Foletta, TTEE's for the Foletta Family Trust DTD 1/30/15, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000306 · edgardoc.xml · nonDerivative · entry 1

FOLETTA MARK G · CIK 0001236389 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · by Trust

Disclosed balance after: 14,187

F1 · shares: On June 6, 2020, Mr. Foletta adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Foletta. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F2 · price: This transaction was executed in multiple trades at prices ranging from $336.40 to $337.07. 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.

F3 · ownership.nature: Shares are held by the Mark G. and Mary E. Foletta, TTEE's for the Foletta Family Trust DTD 1/30/15, with respect to which the reporting person is a trustee.

SEC source: 0001093557-20-000304 · edgardoc.xml · nonDerivative · entry 1

Sylvain Jereme M · CIK 0001681267 · SVP, Finance & CAO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 11,900

F1 · shares: 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.

F2 · price: This transaction was executed in multiple trades at prices ranging from $336.2100 to $336.8834. 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.

F3 · balance_after: Included in this number are 9,169 unvested restricted stock units, 5,483 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 2,412 of which were granted on March 8, 2019 and shall vest through March 8, 2022 and 1,274 of which were granted on November 8, 2018 and shall vest through November 8, 2021.

SEC source: 0001093557-20-000302 · edgardoc.xml · nonDerivative · entry 1

Stern Sadie · CIK 0001797971 · EVP Chief Human Resources Off

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 7,707

F1 · shares: Represents a grant of restricted stock units that vests in four annual installments on November 08, 2021, November 8, 2022, November 8, 2023 and November 8, 2024. Share units represent a contingent right to receive one share of Dexcom, Inc. common stock.

F2 · balance_after: Included in this number are 7,707 unvested restricted stock units, 7,707 of which were granted on November 8, 2020 and shall vest through November 8, 2024.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 14

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 128,747

F1 · shares: On July 31, 2020, 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 13

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 128,967

F1 · shares: On July 31, 2020, 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 12

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 129,477

F1 · shares: On July 31, 2020, 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.

F12 · price: This transaction was executed in multiple trades at prices ranging from $351.405 to $352.115. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 11

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 129,777

F1 · shares: On July 31, 2020, 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.

F11 · price: This transaction was executed in multiple trades at prices ranging from $350.175 to $350.30. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 10

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 130,386

F1 · shares: On July 31, 2020, 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 9

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 131,186

F1 · shares: On July 31, 2020, 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.

F10 · price: This transaction was executed in multiple trades at prices ranging from $345.255 to $345.265. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 8

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 131,386

F1 · shares: On July 31, 2020, 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 7

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 131,786

F1 · shares: On July 31, 2020, 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.

F9 · price: This transaction was executed in multiple trades at prices ranging from $342.30 to $342.85. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 6

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 132,333

F1 · shares: On July 31, 2020, 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.

F8 · price: This transaction was executed in multiple trades at prices ranging from $341.125 to $342.00. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 5

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 133,763

F1 · shares: On July 31, 2020, 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.

F7 · price: This transaction was executed in multiple trades at prices ranging from $339.28 to $340.26. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 4

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 134,963

F1 · shares: On July 31, 2020, 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.

F6 · price: This transaction was executed in multiple trades at prices ranging from $337.015 to $337.769. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 3

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 136,639

F1 · shares: On July 31, 2020, 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.

F5 · price: This transaction was executed in multiple trades at prices ranging from $335.98 to $336.935. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 2

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 139,067

F1 · shares: On July 31, 2020, 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.

F4 · price: This transaction was executed in multiple trades at prices ranging from $334.94 to $335.89. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000300 · edgardoc.xml · nonDerivative · entry 1

SAYER KEVIN R · CIK 0001286858 · Director · President, CEO and Chairman

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 141,977

F1 · shares: On July 31, 2020, 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.

F2 · price: This transaction was executed in multiple trades at prices ranging from $333.282 to $334.22. 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.

F3 · balance_after: Included in this number are 56,792 unvested restricted stock units, 25,453 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 17,915 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 13,424 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000298 · edgardoc.xml · nonDerivative · entry 7

Pacelli Steven Robert · CIK 0001359098 · EVP Strategy and Corporate Dev

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 61,939

F1 · shares: On June 15, 2020, Mr. Pacelli adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Pacelli. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F3 · balance_after: Included in this number are 22,722 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,494 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000298 · edgardoc.xml · nonDerivative · entry 6

Pacelli Steven Robert · CIK 0001359098 · EVP Strategy and Corporate Dev

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 62,022

F1 · shares: On June 15, 2020, Mr. Pacelli adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Pacelli. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F7 · price: This transaction was executed in multiple trades at prices ranging from $406.75 to $407.33. 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.

F3 · balance_after: Included in this number are 22,722 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,494 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000298 · edgardoc.xml · nonDerivative · entry 5

Pacelli Steven Robert · CIK 0001359098 · EVP Strategy and Corporate Dev

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 62,217

F1 · shares: On June 15, 2020, Mr. Pacelli adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Pacelli. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F6 · price: This transaction was executed in multiple trades at prices ranging from $405.58 to $406.30. 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.

F3 · balance_after: Included in this number are 22,722 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,494 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021.

SEC source: 0001093557-20-000298 · edgardoc.xml · nonDerivative · entry 4

Pacelli Steven Robert · CIK 0001359098 · EVP Strategy and Corporate Dev

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 62,390

F1 · shares: On June 15, 2020, Mr. Pacelli adopted a 10b5-1 Plan. This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Pacelli. The shares set forth above were sold pursuant to the 10b5-1 Plan.

F5 · price: This transaction was executed in multiple trades at prices ranging from $404.37 to $404.93. 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 issurer full information regarding the number of shares and prices at which the transactions were effected.

F3 · balance_after: Included in this number are 22,722 unvested restricted stock units, 8,811 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 7,494 of which were granted on March 8, 2019 and shall vest through March 8, 2022, and 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021.