Allan Reine - 26 Feb 2026 Form 4 Insider Report for Prime Medicine, Inc. (PRME)

Role: Chief Executive Officer, Director
Signature: /s/ Ryan Brown, attorney-in-fact
Issuer symbol: PRME
Transactions as of: 26 Feb 2026
Net transactions value: $0
Form type: 4
Filing time: 27 Feb 2026, 16:52:39 UTC
Previous filing: 05 Aug 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Reine Allan	Chief Executive Officer, Director	C/O PRIME MEDICINE, INC., 60 FIRST STREET, CAMBRIDGE	/s/ Ryan Brown, attorney-in-fact	27 Feb 2026	0001714023

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	PRME	Stock Option (right to buy)	Award	$0	+1,300,000		$0.000000	1,300,000	26 Feb 2026	Common Stock	1,300,000	$4.38	Direct	F1

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

Explanation of Responses:

Id	Content
F1	1/48th of the shares underlying this option vest and become exercisable in substantially equal monthly installments on each monthly anniversary of February 26, 2026, subject to the Reporting Person's continued service on each such vesting date.