Director Christopher J. Twomey filed a Form 4 with the SEC on October 29, 2026, disclosing the exercise of 1,700 stock options and the same-day sale of 1,700 shares of Tandem Diabetes Care Inc. common stock on October 27, 2026.

Key Highlights

  • Option exercise: Twomey acquired 1,700 shares of common stock via a stock option exercise at $19 per share on October 27, 2026.
  • Same-day sale: The 1,700 shares were sold at $19.15 per share on October 27, 2026, pursuant to a Rule 10b5-1 trading plan.
  • Trading plan date: The Rule 10b5-1 plan was adopted by the reporting person on May 19, 2026, according to the filing.
  • Remaining direct holdings: Following the transactions, Twomey directly owned 24,434 shares of common stock.
  • Indirect holdings: Twomey also holds 7,568 shares indirectly through Twomey Family Investments, LLC, and 5,112 shares through the Chris J. Twomey and Rebecca J. Twomey Family Trust UTD September 20, 2002.
  • Expiring options: The exercised options were originally awarded on November 15, 2016 under the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan and were set to expire on November 15, 2026.

Twomey's October 27 Option Exercise and Share Sale at Tandem Diabetes Care

According to the Form 4 filed on October 29, 2026, Christopher J. Twomey, a director at Tandem Diabetes Care Inc. (NASDAQ:TNDM), exercised a stock option covering 1,700 shares of common stock at an exercise price of $19 per share on October 27, 2026. The filing notes the option was originally awarded on November 15, 2016 under the Tandem Diabetes Care, Inc. 2013 Stock Incentive Plan, as amended, and that such options "became exercisable in 12 equal monthly installments beginning on December 15, 2016." The options were set to expire on November 15, 2026.

On the same date, Twomey disposed of all 1,700 shares acquired through the exercise, selling them at $19.15 per share. The filing states the shares "were sold pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 19, 2026." The Form 4 was signed by Jerilyn Laskie as Attorney-in-Fact for Christopher J. Twomey and indicates the transaction box was checked to reflect execution under a Rule 10b5-1(c) plan.

Following these transactions, the filing reports Twomey's direct beneficial ownership stood at 24,434 shares. In addition, 7,568 shares are held indirectly through Twomey Family Investments, LLC, of which Twomey is co-manager and shares voting and investment power, though the filing notes he "disclaims beneficial ownership of such securities... except to the extent of his proportionate pecuniary interest therein." A further 5,112 shares are held by the Chris J. Twomey and Rebecca J. Twomey Family Trust UTD September 20, 2002.

What Was Disclosed

The filing disclosed a same-day option exercise and sale of 1,700 shares of Tandem Diabetes Care common stock by director Christopher J. Twomey on October 27, 2026, conducted under a pre-established Rule 10b5-1 trading plan, with resulting direct ownership of 24,434 shares.