Vosseller Leigh

SEC source: 0001438133-24-000036 · wk-form4_1709244773.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,940

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: 0001438133-24-000036 · wk-form4_1709244773.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,082

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: 0001438133-24-000014 · wk-form4_1708475226.xml · derivative · entry 7

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,371

Underlying: Common Stock · 475 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 25, 2022 pursuant to the 2013 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 2013 Plan.

F7 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on 5/15/2023, 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 5/15/2023, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter.

SEC source: 0001438133-24-000014 · wk-form4_1708475226.xml · derivative · entry 6

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 812

Underlying: Common Stock · 163 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 18, 2021 pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan, as amended, and the agreements related thereto (the 2013 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 2013 Plan.

F5 · derivative.exercise_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 5/15/2022, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter.

F5 · derivative.expiration_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 5/15/2022, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter.

SEC source: 0001438133-24-000014 · wk-form4_1708475226.xml · nonDerivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,675

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: 0001438133-24-000014 · wk-form4_1708475226.xml · nonDerivative · entry 3

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,870

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: 0001438133-24-000014 · wk-form4_1708475226.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,395

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: 0001438133-24-000014 · wk-form4_1708475226.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,462

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: 0001438133-23-000243 · wk-form4_1701292086.xml · derivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 813

Underlying: Common Stock · 406 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 27, 2020 pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan, as amended, and the agreements related thereto (the 2013 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 2013 Plan.

F5 · derivative.exercise_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 5/27/2021, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter.

F5 · derivative.expiration_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 5/27/2021, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter.

SEC source: 0001438133-23-000243 · wk-form4_1701292086.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,299

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: 0001438133-23-000243 · wk-form4_1701292086.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,440

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: 0001438133-23-000228 · wk-form4_1700255401.xml · derivative · entry 8

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,846

Underlying: Common Stock · 474 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 25, 2022 pursuant to the 2013 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 2013 Plan.

F8 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

F8 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000228 · wk-form4_1700255401.xml · derivative · entry 7

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 975

Underlying: Common Stock · 162 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 18, 2021 pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan, as amended, and the agreements related thereto (the 2013 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 2013 Plan.

F6 · derivative.exercise_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

F6 · derivative.expiration_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000228 · wk-form4_1700255401.xml · nonDerivative · entry 5

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,034

F2 · 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: 0001438133-23-000228 · wk-form4_1700255401.xml · nonDerivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,198

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: 0001438133-23-000228 · wk-form4_1700255401.xml · nonDerivative · entry 3

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,724

F2 · 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: 0001438133-23-000228 · wk-form4_1700255401.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,781

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: 0001438133-23-000228 · wk-form4_1700255401.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,619

F1 · shares: 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 May 16, 2023 through November 15, 2023. This transaction is also exempt under Rule 16b-3(c).

SEC source: 0001438133-23-000214 · wk-form4_1699911153.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Indirect · Leigh A. Vosseller Trust

Disclosed balance after: 11,860

F1 · price: This transaction was executed in multiple trades at prices ranging from $15.36 to $15.40 per share. The reported price reflects the weighted average purchase 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 transaction was effected.

F2 · ownership.nature: The securities are held by the Leigh A. Vosseller Trust dated January 17, 2010, of which Leigh Vosseller is the Trustee.

SEC source: 0001438133-23-000192 · wk-form4_1693426755.xml · derivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,219

Underlying: Common Stock · 407 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 27, 2020 pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan, as amended, and the agreements related thereto (the 2013 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 2013 Plan.

F5 · derivative.exercise_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 5/27/2021, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter.

F5 · derivative.expiration_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 5/27/2021, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter.

SEC source: 0001438133-23-000192 · wk-form4_1693426755.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,618

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: 0001438133-23-000192 · wk-form4_1693426755.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,759

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: 0001438133-23-000166 · wk-form4_1692303820.xml · derivative · entry 7

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,320

Underlying: Common Stock · 474 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 25, 2022 pursuant to the 2013 Plan, as amended, and the agreements related thereto.

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 2013 Plan.

F7 · derivative.exercise_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

F7 · derivative.expiration_date: RSU vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000166 · wk-form4_1692303820.xml · derivative · entry 6

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,137

Underlying: Common Stock · 162 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 18, 2021 pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan, as amended, and the agreements related thereto (the 2013 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 2013 Plan.

F5 · derivative.exercise_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 5/15/2022, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter.

F5 · derivative.expiration_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on 5/15/2022, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter.

SEC source: 0001438133-23-000166 · wk-form4_1692303820.xml · nonDerivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,352

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: 0001438133-23-000166 · wk-form4_1692303820.xml · nonDerivative · entry 3

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,516

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: 0001438133-23-000166 · wk-form4_1692303820.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,042

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: 0001438133-23-000166 · wk-form4_1692303820.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,099

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: 0001438133-23-000124 · wf-form4_168549620237948.xml · derivative · entry 6

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,626

Underlying: Common Stock · 406 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 · 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 Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the 2013 Plan).

F8 · derivative.exercise_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterlyinstallments thereafter, subject to the terms of the 2013 Plan.

F8 · derivative.expiration_date: RSU vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterlyinstallments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000124 · wf-form4_168549620237948.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,937

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: 0001438133-23-000124 · wf-form4_168549620237948.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,078

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: 0001438133-23-000124 · wf-form4_168549620237948.xml · derivative · entry 5

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,883

Underlying: Common Stock · 8,883 shares

Expires not disclosed

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

F6 · derivative.exercise_price: Each performance stock unit (PSU) represents a contingent right to receive one share of Tandem Diabetes Care, Inc. (the Company) common stock based upon the achievement of certain pre-defined performance metrics as of December 31, 2025 (the Measurement Date). The number of shares issued may range from 0% to 200% of the amount specified above, based upon (i) Company's actual performance relative to the pre-defined performance metrics, and (ii) subject to the awardee's continuing service through the Measurement Date. If minimum performance metrics are not met, no PSU's will vest.

F6 · derivative.exercise_date: Each performance stock unit (PSU) represents a contingent right to receive one share of Tandem Diabetes Care, Inc. (the Company) common stock based upon the achievement of certain pre-defined performance metrics as of December 31, 2025 (the Measurement Date). The number of shares issued may range from 0% to 200% of the amount specified above, based upon (i) Company's actual performance relative to the pre-defined performance metrics, and (ii) subject to the awardee's continuing service through the Measurement Date. If minimum performance metrics are not met, no PSU's will vest.

F6 · derivative.expiration_date: Each performance stock unit (PSU) represents a contingent right to receive one share of Tandem Diabetes Care, Inc. (the Company) common stock based upon the achievement of certain pre-defined performance metrics as of December 31, 2025 (the Measurement Date). The number of shares issued may range from 0% to 200% of the amount specified above, based upon (i) Company's actual performance relative to the pre-defined performance metrics, and (ii) subject to the awardee's continuing service through the Measurement Date. If minimum performance metrics are not met, no PSU's will vest.

SEC source: 0001438133-23-000124 · wf-form4_168549620237948.xml · derivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 18,037

Underlying: Common Stock · 18,037 shares

Expires not disclosed

F3 · security: Awarded on May 25, 2023 pursuant to the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan (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 thiry-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 thiry-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: 0001438133-23-000081 · wf-form4_168436140977215.xml · derivative · entry 8

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,794

Underlying: Common Stock · 1,897 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 · 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 Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the 2013 Plan).

F6 · derivative.exercise_date: RSU granted on 5/25/2022 vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

F6 · derivative.expiration_date: RSU granted on 5/25/2022 vest as to thirty-three percent (33%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in eight (8) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000081 · wf-form4_168436140977215.xml · derivative · entry 7

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,299

Underlying: Common Stock · 163 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 · 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 Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the 2013 Plan).

F5 · derivative.exercise_date: RSU granted on 5/18/2021 vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

F5 · derivative.expiration_date: RSU granted on 5/18/2021 vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the 15th day of the month that corresponds to the anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000081 · wf-form4_168436140977215.xml · nonDerivative · entry 5

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,672

F2 · 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: 0001438133-23-000081 · wf-form4_168436140977215.xml · nonDerivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,328

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: 0001438133-23-000081 · wf-form4_168436140977215.xml · nonDerivative · entry 3

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,431

F2 · 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: 0001438133-23-000081 · wf-form4_168436140977215.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,488

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: 0001438133-23-000081 · wf-form4_168436140977215.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,325

F1 · shares: 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 16, 2022 through May 15, 2023. This transaction is also exempt under Rule 16b-3(c).

SEC source: 0001438133-23-000070 · wf-form4_168428115683623.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Indirect · Leigh A. Vosseller Trust

Disclosed balance after: 5,660

F1 · ownership.nature: The securities are held by the Leigh A. Vosseller Trust dated January 17, 2010, of which Leigh Vosseller is the Trustee.

SEC source: 0001438133-23-000048 · wf-form4_167771407609190.xml · derivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,032

Underlying: Common Stock · 407 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: Granted pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the "2013 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 2013 Plan.

F5 · derivative.exercise_date: RSUs granted on 5/27/2020 vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

F5 · derivative.expiration_date: RSUs granted on 5/27/2020 vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve (12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000048 · wf-form4_167771407609190.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,692

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: 0001438133-23-000048 · wf-form4_167771407609190.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,858

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: 0001438133-23-000024 · wf-form4_167667230513501.xml · derivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,462

Underlying: Common Stock · 162 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: Granted pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the "2013 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 2013 Plan.

F5 · derivative.exercise_date: RSU granted on 5/18/2021 vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve(12)equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

F5 · derivative.expiration_date: RSU granted on 5/18/2021 vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve(12)equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000024 · wf-form4_167667230513501.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,451

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: 0001438133-23-000024 · wf-form4_167667230513501.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,518

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: 0001438133-22-000253 · wf-form4_166984474715299.xml · derivative · entry 4

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,439

Underlying: Common Stock · 406 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: Granted pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the "2013 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 2013 Plan.

F5 · derivative.exercise_date: RSUs granted on 5/27/2020 vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve(12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

F5 · derivative.expiration_date: RSUs granted on 5/27/2020 vest as to twenty-five percent (25%) of the total number of shares subject to the RSU on the one year anniversary of the grant date, and the remaining shares shall vest in twelve(12) equal quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-22-000253 · wf-form4_166984474715299.xml · nonDerivative · entry 2

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,356

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: 0001438133-22-000253 · wf-form4_166984474715299.xml · nonDerivative · entry 1

Vosseller Leigh · CIK 0001726322 · EVP & CHIEF FINANCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,497

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.