STOCK TITAN

Tandem Diabetes (TNDM) CFO vests RSUs as shares withheld for tax

(Neutral)
(Neutral)
Form Type
4

Rhea-AI Filing Summary

TANDEM DIABETES CARE INC (TNDM) reported insider equity activity by EVP & Chief Financial Officer Leigh Vosseller on August 15, 2026. Two blocks of restricted stock units (RSUs) covering 1,496 and 2,624 underlying shares were converted into common stock, and related RSU entries were removed.

Vosseller acquired 1,496 and 2,624 shares of common stock through these RSU vestings at a conversion price of $0.00 per share. A total of 537 and 942 shares were then withheld by Tandem Diabetes Care at $22.72 per share to satisfy tax withholding obligations; footnotes state that no shares were sold. Following these transactions, 25,580 shares of common stock are reported as held indirectly in the Leigh A. Vosseller Trust, for which Vosseller serves as trustee.

Positive

  • None.

Negative

  • None.
Insider Vosseller Leigh
Role EVP & CHIEF FINANCIAL OFFICER
Type Security Shares Price Value
Exercise Restricted Stock Unit F3, F4, F5 1,496 $0.00 $0.00
Exercise Restricted Stock Unit F6, F4, F7 2,624 $0.00 $0.00
Exercise Common Stock 1,496 $0.00 $0.00
Tax Withholding Common Stock F1 537 $22.72 $12K
Exercise Common Stock 2,624 $0.00 $0.00
Tax Withholding Common Stock F1 942 $22.72 $21K
holding Common Stock F2 -- -- --
Holdings After Transaction: Restricted Stock Unit — 22,854 shares (Direct); Common Stock — 52,040 shares (Direct); Common Stock — 25,580 shares (Indirect, Leigh A. Vosseller Trust)
Footnotes (7)
  1. F1. Shares withheld by the Issuer to satisfy tax withholding requirements upon the vesting of restricted stock units (RSUs). No shares were sold.
  2. F2. The securities are held by the Leigh A. Vosseller Trust dated January 17, 2010, of which Leigh Vosseller is the Trustee.
  3. F3. Awarded on May 23, 2024 pursuant to the Tandem Diabetes Care Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).
  4. 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.
  5. F5. One-third of the RSUs granted on May 23, 2024 vested on May 15, 2025, with the remaining RSUs vesting in eight (8) equal quarterly installments thereafter, subject to the terms of the 2023 Plan.
  6. F6. Awarded on May 30, 2025 pursuant to the 2023 Plan.
  7. F7. One-third of the RSUs granted on May 30, 2025 vested on May 15, 2026, with the remaining RSUs vesting in eight (8) equal quarterly installments thereafter, subject to the terms of the 2023 Plan.
RSUs converted (first block) 1,496 shares Restricted Stock Units converting into common stock on August 15, 2026
RSUs converted (second block) 2,624 shares Restricted Stock Units converting into common stock on August 15, 2026
Shares withheld for taxes (first leg) 537 shares Common shares withheld to satisfy tax withholding obligations at vesting
Shares withheld for taxes (second leg) 942 shares Common shares withheld to satisfy tax withholding obligations at vesting
Tax withholding price $22.72 per share Value used for shares withheld to cover tax obligations
Indirect trust holdings 25,580 shares Common stock held indirectly by the Leigh A. Vosseller Trust after transactions
Restricted Stock Unit financial
"security_title: "Restricted Stock Unit""
A restricted stock unit is a promise from a company to give an employee shares of stock after certain conditions are met, like staying with the company for a set amount of time. It’s like earning a bonus that turns into company stock once you’ve proven your commitment, making it a way to motivate and reward employees.
Long-Term Incentive Plan financial
"pursuant to the Tandem Diabetes Care Inc. 2023 Long-Term Incentive Plan"
A long-term incentive plan is a company program that pays executives or employees with stock, options, or cash tied to multi-year performance goals, where the rewards become theirs only after meeting conditions over time. Think of it as a delayed bonus or retirement-style reward that aligns employees’ interests with shareholders by encouraging them to boost long-term value; investors watch these plans because they affect pay costs, share dilution and management incentives.
contingent right financial
"Each RSU represents a contingent right to receive either one share"
tax withholding requirements financial
"Shares withheld by the Issuer to satisfy tax withholding requirements"
indirect ownership financial
"The securities are held by the Leigh A. Vosseller Trust"

FAQ

What insider transactions did TNDM’s CFO Leigh Vosseller report on August 15, 2026?

On August 15, 2026, CFO Leigh Vosseller reported RSU vestings converting 1,496 and 2,624 RSUs into common stock. The company then withheld 537 and 942 shares to cover tax withholding obligations at $22.72 per share.

Were any of Leigh Vosseller’s Tandem Diabetes Care (TNDM) shares sold in the August 2026 Form 4?

The filing states that no shares were sold. Instead, 537 and 942 shares of common stock were withheld by the issuer solely to satisfy tax withholding requirements triggered by RSU vesting.

How many Tandem Diabetes Care (TNDM) shares are held in the Leigh A. Vosseller Trust?

After the reported transactions, the Form 4 lists 25,580 shares of Tandem Diabetes Care common stock held indirectly through the Leigh A. Vosseller Trust, for which Leigh Vosseller serves as Trustee.

What RSU grants underlie the August 15, 2026 transactions for TNDM?

The transactions relate to RSUs awarded on May 23, 2024 and May 30, 2025 under the 2023 Long-Term Incentive Plan. Each RSU represents a contingent right to receive one share of common stock or cash at Tandem’s discretion.

At what price were shares withheld for taxes in the TNDM August 2026 insider filing?

For tax withholding, Tandem Diabetes Care withheld 537 and 942 shares of common stock at a per-share value of $22.72. The Form 4 identifies these as shares withheld to satisfy tax withholding requirements.

AI-generated analysis. How Rhea-AI works. Not financial advice.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google
Add on Google
Learn about SEC filing dates
SEC Form 4
FORM 4UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number:3235-0287
Estimated average burden
hours per response:0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
Vosseller Leigh

(Last)(First)(Middle)
12400 HIGH BLUFF DRIVE

(Street)
SAN DIEGO CALIFORNIA 92130

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
TANDEM DIABETES CARE INC [ TNDM ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director10% Owner
XOfficer (give title below)Other (specify below)
EVP & CHIEF FINANCIAL OFFICER
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
08/15/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year)2A. Deemed Execution Date, if any (Month/Day/Year)3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeVAmount(A) or (D)Price
Common Stock08/15/2026M1,496A$050,895D
Common Stock08/15/2026F(1)537D$22.7250,358D
Common Stock08/15/2026M2,624A$052,982D
Common Stock08/15/2026F(1)942D$22.7252,040D
Common Stock25,580ILeigh A. Vosseller Trust(2)
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year)3A. Deemed Execution Date, if any (Month/Day/Year)4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year)7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Restricted Stock Unit(3)(4)08/15/2026M1,496 (5) (5)Common Stock1,496$04,486D
Restricted Stock Unit(6)(4)08/15/2026M2,624 (7) (7)Common Stock2,624$018,368D
Explanation of Responses:
1. Shares withheld by the Issuer to satisfy tax withholding requirements upon the vesting of restricted stock units (RSUs). No shares were sold.
2. The securities are held by the Leigh A. Vosseller Trust dated January 17, 2010, of which Leigh Vosseller is the Trustee.
3. Awarded on May 23, 2024 pursuant to the Tandem Diabetes Care Inc. 2023 Long-Term Incentive Plan, as amended, and agreements related thereto (the 2023 Plan).
4. 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.
5. One-third of the RSUs granted on May 23, 2024 vested on May 15, 2025, with the remaining RSUs vesting in eight (8) equal quarterly installments thereafter, subject to the terms of the 2023 Plan.
6. Awarded on May 30, 2025 pursuant to the 2023 Plan.
7. One-third of the RSUs granted on May 30, 2025 vested on May 15, 2026, with the remaining RSUs vesting in eight (8) equal quarterly installments thereafter, subject to the terms of the 2023 Plan.
Remarks:
/s/ Jerilyn Laskie, Attorney-in-Fact for Leigh A. Vosseller08/18/2026
** Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)