[Form 4] GRI Bio, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Walter Marc Hertz, identified as Chief Executive Officer and a director of GRI Bio, Inc. (GRI), reported on Form 4 a transaction dated 08/26/2025 involving stock options. He acquired 26,688 shares of common stock by exercising options with an exercise price of $1.41 per share. Of the options, 17,828 vested in full on the grant date and 8,860 will vest in 12 substantially equal quarterly installments, with the option fully vested on the third anniversary of the grant date. Following the transaction, Mr. Hertz beneficially owns 26,688 shares directly. The filing is signed by an attorney-in-fact, Leanne Kelly.

Insights

Financial Analyst

TL;DR: CEO exercised options to acquire 26,688 shares at $1.41, with most shares vested immediately.

The transaction shows insider acquisition rather than disposition: the CEO exercised a stock option covering 26,688 shares at a $1.41 exercise price. Immediate vesting of 17,828 shares provides instant share ownership while 8,860 shares vest over the next three years in quarterly installments. This increases the CEO's direct equity stake and may modestly affect outstanding shares depending on company capitalization; the filing does not disclose total outstanding share count or the grant's dilutive effect.

Corporate Governance Expert

TL;DR: Option exercise and partial time-based vesting documented; transaction properly reported on Form 4.

The Form 4 documents a routine equity compensation event: an option exercise with a mix of immediately vested and time-based vesting tranches. The filing identifies the reporting person as both CEO and director and includes the vesting schedule details required for transparency. The report is executed by an attorney-in-fact and contains the necessary transaction date and ownership disclosure. No amendments or other governance actions are indicated.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Hertz Walter Marc

(Last) (First) (Middle)

C/O GRI BIO, INC.

2223 AVENIDA DE LA PLAYA, SUITE 208

(Street)

LA JOLLA CA 92037

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
GRI Bio, Inc. [ GRI ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Executive Officer

3. Date of Earliest Transaction (Month/Day/Year)
08/26/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (Right to Buy)	$1.41	08/26/2025		A		26,688		(1)	08/26/2035	Common Stock	26,688	$0	26,688	D

Explanation of Responses:

1. Options to purchase 17,828 shares vested in full upon the date of grant and options to purchase 8,860 shares will vest in 12 substantially equal quarterly installments such that the stock option is fully vested on the third anniversary of the date of grant.

Remarks:

	/s/ Leanne Kelly, Attorney-in-Fact	08/26/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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