TNDM

SEC source: 0001438133-26-000107 · wk-form4_1780431640.xml · derivative · entry 1

Hansen Shannon Marie · CIK 0001908267 · EVP & Chief Legal Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,136

Underlying: Common Stock · 29,136 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents a contingent right to receive either one share of the Issuer's common stock or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F2 · derivative.exercise_date: One-third of such RSUs shall vest on 5/29/2027, and the remaining RSUs shall vest in eight (8) equal quarterly installments on the 15th of the month thereafter subject to the terms of the 2023 Plan.

F2 · derivative.expiration_date: One-third of such RSUs shall vest on 5/29/2027, and the remaining RSUs shall vest in eight (8) equal quarterly installments on the 15th of the month thereafter subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000075 · wk-form4_1779480468.xml · derivative · entry 3

McGroddy-Goetz Kathleen · CIK 0001814371 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,759 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F3 · derivative.exercise_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

F3 · derivative.expiration_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

SEC source: 0001438133-26-000075 · wk-form4_1779480468.xml · nonDerivative · entry 1

McGroddy-Goetz Kathleen · CIK 0001814371 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 26,612

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000080 · wk-form4_1779500208.xml · derivative · entry 4

Allen Dick · CIK 0001582779 · Chair Emeritus

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,759 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F4 · derivative.exercise_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

F4 · derivative.expiration_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

SEC source: 0001438133-26-000080 · wk-form4_1779500208.xml · nonDerivative · entry 1

Allen Dick · CIK 0001582779 · Chair Emeritus

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 28,146

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000074 · wk-form4_1779480402.xml · derivative · entry 3

ROBERTSON REBECCA B · CIK 0001201585 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,759 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F3 · derivative.exercise_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

F3 · derivative.expiration_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

SEC source: 0001438133-26-000074 · wk-form4_1779480402.xml · nonDerivative · entry 1

ROBERTSON REBECCA B · CIK 0001201585 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,542

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000079 · wk-form4_1779480786.xml · derivative · entry 3

Howell Peyton R · CIK 0001528056 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,759 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F3 · derivative.exercise_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

F3 · derivative.expiration_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

SEC source: 0001438133-26-000079 · wk-form4_1779480786.xml · nonDerivative · entry 1

Howell Peyton R · CIK 0001528056 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,836

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000078 · wk-form4_1779480707.xml · derivative · entry 3

Malagueira Joao Paulo Falcao · CIK 0001937552 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,759 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F3 · derivative.exercise_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

F3 · derivative.expiration_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

SEC source: 0001438133-26-000078 · wk-form4_1779480707.xml · nonDerivative · entry 1

Malagueira Joao Paulo Falcao · CIK 0001937552 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,458

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000076 · wk-form4_1779480532.xml · derivative · entry 3

Sodhi Rajwant · CIK 0001715325 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,759 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F3 · derivative.exercise_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

F3 · derivative.expiration_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

SEC source: 0001438133-26-000076 · wk-form4_1779480532.xml · nonDerivative · entry 1

Sodhi Rajwant · CIK 0001715325 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,280

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000072 · wk-form4_1779480278.xml · derivative · entry 3

Cha Myoungil · CIK 0001934068 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,759 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F3 · derivative.exercise_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

F3 · derivative.expiration_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

SEC source: 0001438133-26-000072 · wk-form4_1779480278.xml · nonDerivative · entry 1

Cha Myoungil · CIK 0001934068 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,458

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000073 · wk-form4_1779480372.xml · derivative · entry 5

TWOMEY CHRISTOPHER J · CIK 0001238935 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 8,759 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F5 · derivative.exercise_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

F5 · derivative.expiration_date: On May 21, 2025, the Reporting Person was granted 8,759 RSUs, all of which vested and converted into shares of the Issuers common stock on the one-year anniversary thereof in accordance with the 2023 Plan.

SEC source: 0001438133-26-000073 · wk-form4_1779480372.xml · nonDerivative · entry 1

TWOMEY CHRISTOPHER J · CIK 0001238935 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,434

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000077 · wk-form4_1779480632.xml · derivative · entry 1

Beaver Sandra · CIK 0001944884 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,110

Underlying: Common Stock · 5,110 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F2 · derivative.exercise_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

F2 · derivative.expiration_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000075 · wk-form4_1779480468.xml · derivative · entry 2

McGroddy-Goetz Kathleen · CIK 0001814371 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,220

Underlying: Common Stock · 10,220 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F2 · derivative.exercise_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

F2 · derivative.expiration_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000080 · wk-form4_1779500208.xml · derivative · entry 3

Allen Dick · CIK 0001582779 · Chair Emeritus

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,220

Underlying: Common Stock · 10,220 shares

Expires not disclosed

F2 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F3 · derivative.exercise_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

F3 · derivative.expiration_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000074 · wk-form4_1779480402.xml · derivative · entry 2

ROBERTSON REBECCA B · CIK 0001201585 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,220

Underlying: Common Stock · 10,220 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F2 · derivative.exercise_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

F2 · derivative.expiration_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000079 · wk-form4_1779480786.xml · derivative · entry 2

Howell Peyton R · CIK 0001528056 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,220

Underlying: Common Stock · 10,220 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F2 · derivative.exercise_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

F2 · derivative.expiration_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000078 · wk-form4_1779480707.xml · derivative · entry 2

Malagueira Joao Paulo Falcao · CIK 0001937552 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,220

Underlying: Common Stock · 10,220 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F2 · derivative.exercise_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

F2 · derivative.expiration_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000076 · wk-form4_1779480532.xml · derivative · entry 2

Sodhi Rajwant · CIK 0001715325 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,220

Underlying: Common Stock · 10,220 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F2 · derivative.exercise_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

F2 · derivative.expiration_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000072 · wk-form4_1779480278.xml · derivative · entry 2

Cha Myoungil · CIK 0001934068 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,220

Underlying: Common Stock · 10,220 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F2 · derivative.exercise_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

F2 · derivative.expiration_date: Such RSUs were granted to the Reporting Person on May 20, 2026, and will vest on the one-year anniversary thereof, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000073 · wk-form4_1779480372.xml · derivative · entry 4

TWOMEY CHRISTOPHER J · CIK 0001238935 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,220

Underlying: Common Stock · 10,220 shares

Expires not disclosed

F3 · derivative.exercise_price: Each restricted stock units (RSU) represents a contingent right to receive either one share of the Issuers common stock or cash in lieu thereof, at the Issuers discretion, in accordance with the terms of the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F4 · derivative.exercise_date: RSU will vest on the one-year anniversary of the grant date, subject to the terms of the 2023 Plan.

F4 · derivative.expiration_date: RSU will vest on the one-year anniversary of the grant date, subject to the terms of the 2023 Plan.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · derivative · entry 11

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 15,335

Underlying: Common Stock · 7,667 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · security: Awarded on May 30, 2025 pursuant to the 2023 Plan.

F5 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F10 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2026, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F10 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2026, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · derivative · entry 10

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,387

Underlying: Common Stock · 1,097 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F7 · security: Awarded on May 23, 2024 pursuant to the 2023 Plan.

F5 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F8 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2025, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F8 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2025, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · derivative · entry 9

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,503 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · security: Awarded on May 25, 2023 pursuant to the Tandem Diabetes Care Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F5 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F6 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2024, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F6 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2024, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · nonDerivative · entry 7

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 7,160

F2 · kind: The reporting person is voluntarily reporting the acquisition of shares of common stock pursuant to the Tandem Diabetes Care, Inc. Amended and Restated 2013 Employee Stock Purchase Plan (ESPP), for the ESPP purchase period of November 18, 2025, through May 15, 2026. This transaction is also exempt under Rule 16b-3(c).

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · nonDerivative · entry 6

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,823

F1 · kind: Shares withheld by Tandem Diabetes Care Inc. (the Company) to satisfy tax withholding requirements on vesting of restricted stock units (RSU). No shares were sold.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · nonDerivative · entry 5

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,937

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · nonDerivative · entry 4

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,270

F1 · kind: Shares withheld by Tandem Diabetes Care Inc. (the Company) to satisfy tax withholding requirements on vesting of restricted stock units (RSU). No shares were sold.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · nonDerivative · entry 3

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,859

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · nonDerivative · entry 2

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,762

F1 · kind: Shares withheld by Tandem Diabetes Care Inc. (the Company) to satisfy tax withholding requirements on vesting of restricted stock units (RSU). No shares were sold.

SEC source: 0001438133-26-000066 · wk-form4_1779221602.xml · nonDerivative · entry 1

Gasser Elizabeth Anne · CIK 0001866283 · EVP, Chief Strategy Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,569

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · derivative · entry 11

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,992

Underlying: Common Stock · 10,496 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · security: Awarded on May 30, 2025 pursuant to the 2023 Plan.

F5 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F10 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2026, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F10 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2026, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · derivative · entry 10

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 5,982

Underlying: Common Stock · 1,496 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F7 · security: Awarded on May 23, 2024 pursuant to the 2023 Plan.

F5 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F8 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2025, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F8 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2025, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · derivative · entry 9

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,503 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · security: Awarded on May 25, 2023 pursuant to the Tandem Diabetes Care Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F5 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F6 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2024, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F6 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2024, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · nonDerivative · entry 7

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 49,399

F2 · kind: The reporting person is voluntarily reporting the acquisition of shares of common stock pursuant to the Tandem Diabetes Care, Inc. Amended and Restated 2013 Employee Stock Purchase Plan (ESPP), for the ESPP purchase period of November 18, 2025, through May 15, 2026. This transaction is also exempt under Rule 16b-3(c).

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · nonDerivative · entry 6

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 48,063

F1 · kind: Shares withheld by Tandem Diabetes Care Inc. (the Company) to satisfy tax withholding requirements on vesting of restricted stock units (RSU). No shares were sold.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · nonDerivative · entry 5

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 51,829

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · nonDerivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,333

F1 · kind: Shares withheld by Tandem Diabetes Care Inc. (the Company) to satisfy tax withholding requirements on vesting of restricted stock units (RSU). No shares were sold.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · nonDerivative · entry 3

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,870

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 40,374

F1 · kind: Shares withheld by Tandem Diabetes Care Inc. (the Company) to satisfy tax withholding requirements on vesting of restricted stock units (RSU). No shares were sold.

SEC source: 0001438133-26-000056 · wk-form4_1779221027.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 40,914

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001438133-26-000068 · wk-form4_1779221737.xml · derivative · entry 10

Carpenter Rick · CIK 0001513889 · EVP & Chief Technology Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,878

Underlying: Common Stock · 6,439 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F8 · security: Awarded on May 30, 2025 pursuant to the 2023 Plan.

F4 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F9 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2026, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F9 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2026, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000068 · wk-form4_1779221737.xml · derivative · entry 9

Carpenter Rick · CIK 0001513889 · EVP & Chief Technology Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,589

Underlying: Common Stock · 898 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F6 · security: Awarded on May 23, 2024 pursuant to the 2023 Plan.

F4 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F7 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2025, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F7 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2025, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000068 · wk-form4_1779221737.xml · derivative · entry 8

Carpenter Rick · CIK 0001513889 · EVP & Chief Technology Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,437 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · security: Awarded on May 25, 2023 pursuant to the Tandem Diabetes Care Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).

F4 · derivative.exercise_price: Each RSU represents a contingent right to receive either one share of common stock of the Issuer or cash in lieu thereof, at the Issuer's discretion, in accordance with the terms of the 2023 Plan.

F5 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2024, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

F5 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2024, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-26-000068 · wk-form4_1779221737.xml · nonDerivative · entry 7

Carpenter Rick · CIK 0001513889 · EVP & Chief Technology Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 30,918

F2 · kind: The reporting person is voluntarily reporting the acquisition of shares of common stock pursuant to the Tandem Diabetes Care, Inc. Amended and Restated 2013 Employee Stock Purchase Plan (ESPP), for the ESPP purchase period of November 18, 2025, through May 15, 2026. This transaction is also exempt under Rule 16b-3(c).