HANSEN BRIAN B

SEC source: 0001542377-26-000004 · form4-06172026_040612.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · Director · Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 126,937

F1 · kind: Represents shares withheld to satisfy withholding tax obligations upon the vesting of restricted stock units.

SEC source: 0001542377-26-000002 · form4-05212026_050503.xml · derivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · Director · Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 124,193

Underlying: Common Stock · 124,193 shares

Expires 2036-05-18

F4 · derivative.exercise_date: The options vest in 48 equal monthly installments commencing on May 19, 2026, subject to the Reporting Person's continuous service with the Issuer as of the applicable vesting date.

SEC source: 0001542377-26-000002 · form4-05212026_050503.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · Director · Chief Commercial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 132,357

F1 · shares: Represents a restricted stock unit ("RSU") grant. The RSUs vest in eight equal installments with the first installment vesting on June 15, 2026 and the remaining seven installments vesting in six month increments commencing on November 15, 2026, subject to the Reporting Person's continuous service with the Issuer as of the applicable vesting date.

F2 · price: Each RSU represents a contingent right to receive one share of the Issuer's common stock.

F3 · balance_after: Effective October 17, 2025, the Issuer effected a 1-for-20 reverse stock split of the Issuer's common stock. The number of securities reported herein have been adjusted to reflect the reverse stock split.

SEC source: 0001415889-25-014860 · form4-05292025_040502.xml · derivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,187,987

Underlying: Common Stock · 1,187,987 shares

Expires 2035-05-22

F3 · derivative.exercise_date: The options vest in 48 equal monthly installments commencing on June 23, 2025, subject to the Reporting Person's continuous service with the Issuer as of the applicable vesting date.

SEC source: 0001415889-25-014860 · form4-05292025_040502.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 842,084

F1 · shares: Represents a restricted stock unit ("RSU") grant. The RSUs vest in eight equal installments with the first installment vesting on June 15, 2025 and the remaining seven installments vesting in six month increments commencing on November 15, 2025, subject to the Reporting Person's continuous service with the Issuer as of the applicable vesting date.

F2 · price: Each RSU represents a contingent right to receive one share of the Issuer's common stock.

SEC source: 0001438133-23-000245 · wk-form4_1701292127.xml · derivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F2 · 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).

F3 · 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.

F4 · 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.

F4 · 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: 0001438133-23-000245 · wk-form4_1701292127.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,622

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: 0001438133-23-000245 · wk-form4_1701292127.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,757

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: 0001438133-23-000230 · wk-form4_1700255433.xml · derivative · entry 7

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

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 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: 0001438133-23-000230 · wk-form4_1700255433.xml · derivative · entry 6

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

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 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 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: 0001438133-23-000230 · wk-form4_1700255433.xml · nonDerivative · entry 5

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,351

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: 0001438133-23-000230 · wk-form4_1700255433.xml · nonDerivative · entry 4

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,508

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: 0001438133-23-000230 · wk-form4_1700255433.xml · nonDerivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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: 0001438133-23-000230 · wk-form4_1700255433.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,088

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: 0001438133-23-000230 · wk-form4_1700255433.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,926

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: 0001438133-23-000189 · wk-form4_1693426472.xml · derivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F2 · 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).

F3 · 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.

F4 · 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.

F4 · 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: 0001438133-23-000189 · wk-form4_1693426472.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,925

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: 0001438133-23-000189 · wk-form4_1693426472.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,060

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: 0001438133-23-000172 · wk-form4_1692304345.xml · derivative · entry 6

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F5 · security: Awarded on May 25, 2022 pursuant to the 2013 Plan, as amended, and the agreements related thereto.

F3 · derivative.exercise_price: Each restricted stock unit ("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 the2013 Plan.

F6 · 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.

F6 · 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: 0001438133-23-000172 · wk-form4_1692304345.xml · derivative · entry 5

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F2 · 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)

F3 · derivative.exercise_price: Each restricted stock unit ("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 the2013 Plan.

F4 · 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.

F4 · 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: 0001438133-23-000172 · wk-form4_1692304345.xml · nonDerivative · entry 4

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,653

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: 0001438133-23-000172 · wk-form4_1692304345.xml · nonDerivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,810

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: 0001438133-23-000172 · wk-form4_1692304345.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,336

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: 0001438133-23-000172 · wk-form4_1692304345.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,390

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: 0001438133-23-000130 · wf-form4_168549725116547.xml · derivative · entry 5

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F6 · 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).

F7 · 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 quarterly installments thereafter, subject to the terms of the 2013 Plan.

F7 · 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 quarterly installments thereafter, subject to the terms of the 2013 Plan.

SEC source: 0001438133-23-000130 · wf-form4_168549725116547.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,228

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: 0001438133-23-000130 · wf-form4_168549725116547.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,363

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: 0001438133-23-000130 · wf-form4_168549725116547.xml · derivative · entry 4

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,883

Underlying: Common Stock · 8,883 shares

Expires not disclosed

F2 · security: Awarded on May 25, 2023 pursuant to the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan (the 2023 Plan).

F5 · 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.

F5 · 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.

F5 · 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: 0001438133-23-000130 · wf-form4_168549725116547.xml · derivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 18,037

Underlying: Common Stock · 18,037 shares

Expires not disclosed

F2 · security: Awarded on May 25, 2023 pursuant to the Tandem Diabetes Care, Inc. 2023 Long-Term Incentive Plan (the 2023 Plan).

F3 · derivative.exercise_price: Each restricted stock unit (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.

F4 · 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.

F4 · 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: 0001438133-23-000084 · wf-form4_168436168222335.xml · derivative · entry 7

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F3 · 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 5/25/2022 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.

F5 · 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: 0001438133-23-000084 · wf-form4_168436168222335.xml · derivative · entry 6

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F3 · 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).

F4 · 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.

F4 · 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: 0001438133-23-000084 · wf-form4_168436168222335.xml · nonDerivative · entry 5

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,957

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: 0001438133-23-000084 · wf-form4_168436168222335.xml · nonDerivative · entry 4

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,584

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: 0001438133-23-000084 · wf-form4_168436168222335.xml · nonDerivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,687

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: 0001438133-23-000084 · wf-form4_168436168222335.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,741

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: 0001438133-23-000084 · wf-form4_168436168222335.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,578

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: 0001438133-23-000040 · wf-form4_167771216235917.xml · derivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F2 · security: Granted pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the "2013 Plan").

F3 · 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.

F4 · 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.

F4 · 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: 0001438133-23-000040 · wf-form4_167771216235917.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,947

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: 0001438133-23-000040 · wf-form4_167771216235917.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 9,101

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: 0001438133-23-000014 · wf-form4_167667076532391.xml · derivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F2 · security: Granted pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the "2013 Plan").

F3 · 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.

F4 · 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.

F4 · 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: 0001438133-23-000014 · wf-form4_167667076532391.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,694

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: 0001438133-23-000014 · wf-form4_167667076532391.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,756

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: 0001438133-22-000245 · wf-form4_166984380665218.xml · derivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL 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.

F2 · security: Granted pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the "2013 Plan").

F3 · 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.

F4 · 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.

F4 · 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: 0001438133-22-000245 · wf-form4_166984380665218.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,594

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: 0001438133-22-000245 · wf-form4_166984380665218.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,726

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: 0001438133-22-000229 · wf-form4_166872881141419.xml · derivative · entry 4

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,624

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: 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: 0001438133-22-000229 · wf-form4_166872881141419.xml · nonDerivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,320

F2 · 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"), forthe ESPP purchase period of May 17, 2022 through November 15, 2022. This transaction is also exempt under Rule 16b-3(c).

SEC source: 0001438133-22-000229 · wf-form4_166872881141419.xml · nonDerivative · entry 2

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,319

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: 0001438133-22-000229 · wf-form4_166872881141419.xml · nonDerivative · entry 1

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,372

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: 0001438133-22-000203 · wf-form4_166197930811221.xml · derivative · entry 3

HANSEN BRIAN B · CIK 0001542377 · EVP & CHIEF COMMERCIAL OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,845

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.

F2 · security: Granted pursuant to the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan (the "2013 Plan").

F3 · 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.

F4 · 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.

F4 · 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.