Definium Therapeutics, Inc. 4

Mark Sullivan, Chief Legal Officer of Definium Therapeutics, Inc., received an award of 125,000 common shares as a performance-based equity grant that increased his direct holdings to 508,279 shares.

On September 14, 2026, Mark Sullivan, Chief Legal Officer of Definium Therapeutics, Inc., reported the acquisition of 125,000 common shares at a stated price of $0.00 per share, representing the third tranche of performance share units originally granted on March 12, 2025. These shares remain subject to vesting based on Mr. Sullivan’s continued employment through March 12, 2028 and the achievement of specified clinical and regulatory milestones. Following this award, his direct ownership increased to 508,279 common shares, which also includes 208 shares previously acquired under the company’s 2024 Employee Share Purchase Plan on August 17, 2026. With no trading price data provided, the aggregate value of both the award and his resulting holdings cannot be precisely quantified from the filing alone.

Filing Facts

CIK

1813814

Ticker

DFTX

Form

4

Source Type

fda

Accession

0001193125-26-389889

Alert Tier

5