John F. Sheridan, President and Chief Executive Officer of Tandem Diabetes Care Inc. (NASDAQ:TNDM), filed a Form 4 on August 18, 2026, disclosing restricted stock unit vesting transactions dated August 15, 2026.

Key Highlights

  • Two RSU grants vested: 5,982 shares of common stock were acquired under an RSU award granted May 23, 2024, and 9,934 shares were acquired under an RSU award granted May 30, 2025, both at $0 conversion price.
  • Tax withholding disposals: 3,044 shares were withheld at $22.72 per share in connection with the May 2024 grant, and 5,055 shares were withheld at $22.72 per share in connection with the May 2025 grant, to satisfy tax obligations.
  • No open-market sales: According to the filing, "No shares were sold"; all disposals were shares withheld by the issuer for tax withholding purposes.
  • Remaining RSU holdings: Following the transactions, Sheridan held 17,947 RSUs from the May 2024 grant and 69,537 RSUs from the May 2025 grant, both directly owned.
  • Post-transaction ownership: Sheridan's direct beneficial ownership of common stock stood at 160,260 shares following all reported transactions.
  • Plan basis: Both RSU awards were granted pursuant to the Tandem Diabetes Care Inc. 2023 Long-Term Incentive Plan, as amended.

RSU Vesting Details for Tandem Diabetes Care's President and CEO

According to the filing, the transactions on August 15, 2026, involved the vesting of restricted stock units from two separate grants. The first, awarded on May 23, 2024, resulted in 5,982 shares of common stock being acquired (transaction code M) at $0, with 3,044 shares subsequently withheld by the issuer at $22.72 per share to cover tax withholding requirements. The filing notes that each RSU represents a contingent right to receive either one share of common stock or cash in lieu thereof, at the issuer's discretion, under the 2023 Plan.

The second RSU grant, awarded on May 30, 2025, resulted in 9,934 shares being acquired at $0, with 5,055 shares withheld at $22.72 per share for the same tax withholding purpose. The filing states that one-third of the RSUs granted on May 30, 2025, vested on May 15, 2026, with the remaining RSUs vesting in eight equal quarterly installments thereafter, subject to the terms of the 2023 Plan. Tandem Diabetes Care is a medical device company focused on insulin delivery products, and Sheridan serves as both a director and an officer of the issuer.

After all four reported transactions, Sheridan's direct beneficial ownership of common stock was reported as 160,260 shares. The filing was signed by Jerilyn Laskie as Attorney-in-Fact for John F. Sheridan and bears a filing date of August 18, 2026.

What Was Disclosed

The filing reported the vesting of two RSU grants held by Tandem Diabetes Care's President and CEO, the withholding of shares to satisfy tax obligations at $22.72 per share, and the resulting beneficial ownership totals for both common stock and remaining RSUs.