Stephanie Kenney, Chief Corporate Affairs Officer of Atrium Therapeutics, Inc., filed a statement of changes in beneficial ownership on September 22, 2026, reporting a transaction dated September 18, 2026, involving common stock of the company.

Key Highlights

  • Reporting person: Stephanie Kenney, identified as Chief Corporate Affairs Officer of Atrium Therapeutics, Inc.
  • Transaction type: 2,375 shares of common stock were disposed of (code F) at a price of $8.95 per share on September 18, 2026.
  • Purpose of disposal: According to the filing, the shares were "withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting of restricted stock units."
  • Remaining ownership: Following the transaction, Kenney directly beneficially owned 33,085 shares of common stock.
  • Filing date: The statement was signed by Brendan Winslow as Attorney-in-Fact on September 22, 2026.

Kenney's RSU Vesting Triggers Tax-Related Share Reduction at Atrium Therapeutics

Atrium Therapeutics, Inc. (NASDAQ:RNA) is the issuer named in this filing. According to the disclosure, Stephanie Kenney, serving as Chief Corporate Affairs Officer, reported a single non-derivative transaction in the company's common stock. The transaction, coded "F," reflects shares withheld by the issuer rather than a voluntary open-market sale by the officer.

The filing explains that the 2,375 shares disposed of at $8.95 per share were withheld by Atrium Therapeutics to cover tax withholding obligations triggered by the vesting of restricted stock units. This type of transaction is a standard mechanism by which companies settle the tax liability an employee incurs when equity awards vest. No derivative securities were reported in Table II of the filing, and no open-market purchases or sales were disclosed. After the withholding event, Kenney held 33,085 shares of common stock directly, as reported in the filing. The statement was filed by one reporting person and was signed by Brendan Winslow as Attorney-in-Fact on September 22, 2026.

What Was Disclosed

The filing reported that 2,375 shares of Atrium Therapeutics common stock were withheld from Stephanie Kenney at $8.95 per share on September 18, 2026, to satisfy tax obligations arising from RSU vesting, leaving her with direct beneficial ownership of 33,085 shares.