[Form 4] Equillium, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Tom Penny, Principal Accounting Officer and director at Equillium, Inc. (EQ), was granted an employee stock option on 08/29/2025. The option permits purchase of 525,000 shares of common stock at an exercise price of $1.74 per share and expires on 08/28/2035. Under the stated vesting schedule, 25% of the option vests on the first anniversary of the vesting commencement date and the remainder vests monthly over the following three years. The shares reported as beneficially owned following the grant are 525,000, held directly by the reporting person.

Positive

• Alignment with shareholders: Time-based equity grant links executive compensation to future stock performance
• Retention-focused vesting: 25% after one year with monthly vesting thereafter supports multi-year retention

Negative

• Dilution risk: Grant of 525,000 options could dilute existing shareholders depending on total shares outstanding
• Limited detail provided: Filing does not disclose aggregate outstanding options, current market price, or performance-based conditions

Insights

Securities Analyst

TL;DR: A sizable 10-year option grant aligns the officer with shareholder value but creates potential near-term dilution as it vests.

The grant of 525,000 options at $1.74 establishes a long-dated incentive tied to future stock performance through 2035. The four-year vesting framework (25% after one year, then monthly over three years) is standard for executive retention. For investors, the key considerations are the option count relative to outstanding shares and whether exercise price materially exceeds current market price; that data is not provided in this filing. This disclosure is routine compensation reporting and does not include performance-based vesting terms or change-in-control provisions.

Corporate Governance Expert

TL;DR: The grant is a typical retention tool for an officer; governance impact depends on aggregate equity compensation practices.

The option’s structure—time-based vesting over four years and a ten-year term—is consistent with common governance practices for executive incentives. The filing identifies direct beneficial ownership of 525,000 shares post-grant, confirming no indirect holdings flagged. Absent aggregate dilution metrics or board approval details in this filing, material governance concerns cannot be assessed from this single disclosure.

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

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

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^*

Tom Penny

(Last) (First) (Middle)

2223 AVENIDA DE LA PLAYA, SUITE 105

(Street)

LA JOLLA CA 92037

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Equillium, Inc. [ EQ ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Principal Accounting Officer

3. Date of Earliest Transaction (Month/Day/Year)
08/29/2025

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
Employee Stock Option (right to buy)	$1.74	08/29/2025		A		525,000		(1)	08/28/2035	Common Stock	525,000	$0	525,000	D

Explanation of Responses:

1. Twenty-five percent of the shares subject to the option vests on the first anniversary of the vesting commencement date, and the remainder vests in 36 equal monthly installments thereafter for the following three years.

	/s/ Penny Tom	09/02/2025
	** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What transaction did Tom Penny report on Form 4 for Equillium (EQ)?

The Form 4 reports an employee stock option grant of 525,000 shares with an exercise price of $1.74 dated 08/29/2025.

What is the vesting schedule for the option reported by Tom Penny (EQ)?

The option vests 25% on the first anniversary of the vesting commencement date, with the remainder vesting in 36 equal monthly installments over the next three years.

When does the option reported in the EQ Form 4 expire?

The option expires on 08/28/2035.

How many shares does Tom Penny beneficially own following the reported transaction?

The filing reports 525,000 shares beneficially owned following the grant.

What officer role does Tom Penny hold at Equillium (EQ)?

The Form 4 lists Tom Penny as a Principal Accounting Officer and indicates an officer relationship.