Leigh A. Vosseller - 15 Aug 2025 Form 4 Insider Report for TANDEM DIABETES CARE INC (TNDM)

Role
EVP & CHIEF FINANCIAL OFFICER
Signature
/s/ Rachel Malina, Attorney-in-Fact for Leigh A. Vosseller
Issuer symbol
TNDM
Transactions as of
15 Aug 2025
Net transactions value
-$11,610
Form type
4
Filing time
19 Aug 2025, 18:14:22 UTC
Previous filing
11 Aug 2025
Next filing
19 Nov 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Vosseller Leigh EVP & CHIEF FINANCIAL OFFICER 12400 HIGH BLUFF DRIVE, SAN DIEGO /s/ Rachel Malina, Attorney-in-Fact for Leigh A. Vosseller 19 Aug 2025 0001726322

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction TNDM Common Stock Options Exercise $0 +1,503 +4.4% $0.000000 35,301 15 Aug 2025 Direct
transaction TNDM Common Stock Tax liability $5,821 -538 -1.5% $10.82 34,763 15 Aug 2025 Direct F1
transaction TNDM Common Stock Options Exercise $0 +1,495 +4.3% $0.000000 36,258 15 Aug 2025 Direct
transaction TNDM Common Stock Tax liability $5,789 -535 -1.5% $10.82 35,723 15 Aug 2025 Direct F1
holding TNDM Common Stock 25,580 15 Aug 2025 Leigh A. Vosseller Trust F2

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction TNDM Restricted Stock Unit Options Exercise $0 -1,503 -25% $0.000000 4,509 15 Aug 2025 Common Stock 1,503 Direct F3, F4, F5
transaction TNDM Restricted Stock Unit Options Exercise $0 -1,495 -12% $0.000000 10,469 15 Aug 2025 Common Stock 1,495 Direct F4, F6, F7
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 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.
F2 The securities are held by the Leigh A. Vosseller Trust dated January 17, 2010, of which Leigh Vosseller is the Trustee.
F3 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 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 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 Awarded on May 23, 2024 pursuant to the 2023 Plan.
F7 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.