A Form 4 filed on September 14, 2026, reports that Daniel Karlin, Chief Medical Officer of Definium Therapeutics, Inc. (NASDAQ:DFTX), acquired 200,000 common shares at $0.00 as the third tranche of a performance share unit grant, bringing his total beneficial ownership to 803,699 shares.

Key Highlights

  • Transaction date: September 14, 2026, with transaction code "A" (acquisition) for 200,000 common shares at $0.00.
  • Nature of grant: The shares represent the third tranche of performance share units granted effective March 12, 2025, subject to continued employment through March 12, 2028.
  • Milestone conditions: Each performance share unit represented a contingent right to receive one common share based on the achievement of certain clinical and regulatory milestones set forth in the Performance Share Unit Award Agreement.
  • Total beneficial ownership: Following the transaction, Karlin directly holds 803,699 common shares.
  • ESPP purchase included: The post-transaction total includes 417 shares acquired under the Definium Therapeutics, Inc. 2024 Employee Share Purchase Plan on August 17, 2026.

Details of the Performance Share Unit Award and Resulting Ownership

According to the filing, Daniel Karlin, serving as Chief Medical Officer of Definium Therapeutics, Inc., reported the acquisition of 200,000 common shares on September 14, 2026. The shares were acquired at a price of $0.00 and carry transaction code "A." The filing describes these shares as "the third tranche of performance share units granted effective March 12, 2025."

The filing further discloses that the shares "remain subject to vesting based on the Reporting Person's continued employment through March 12, 2028." Each performance share unit, according to the filing, "represented a contingent right to receive one common share based on, and subject to, the achievement of certain clinical and regulatory milestones set forth in the Performance Share Unit Award Agreement."

Following the reported transaction, Karlin's total beneficial ownership stands at 803,699 common shares held directly. The filing notes that this figure includes 417 shares acquired under the Definium Therapeutics, Inc. 2024 Employee Share Purchase Plan on August 17, 2026. The Form 4 was signed by Mark Sullivan as Attorney-in-Fact for Dan Karlin on September 14, 2026.

What Was Disclosed

The filing discloses the acquisition of 200,000 common shares by Definium Therapeutics' Chief Medical Officer as the third tranche of a March 2025 performance share unit grant, with vesting contingent on continued employment and milestone achievement through March 2028.