Mark Sullivan - 03 Feb 2026 Form 4 Insider Report for Definium Therapeutics, Inc. (DFTX)

Role: Chief Legal Officer
Signature: /s/ Mark Sullivan
Issuer symbol: DFTX
Transactions as of: 03 Feb 2026
Net transactions value: $0
Form type: 4
Filing time: 05 Feb 2026, 16:55:45 UTC
Previous filing: 29 Dec 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Sullivan Mark	Chief Legal Officer	C/O DEFINIUM THERAPEUTICS, INC., ONE WORLD TRADE CENTER, SUITE 8500, NEW YORK	/s/ Mark Sullivan	05 Feb 2026	0001331843

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	DFTX	Common Shares	Award	$0	+125,000	+44%	$0.000000	407,576	03 Feb 2026	Direct	F1

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	These shares represent restricted stock units ("RSUs"). Each RSU represents a contingent right to receive one common share of the Issuer. The RSUs vest in 16 equal quarterly installments beginning on June 1, 2026, subject to the Reporting Person providing continuous service to the Issuer on each such vesting date.