Equillium (EQ) COO reports December 2025 stock sales under 10b5-1 plan

Rhea-AI Filing Summary

Equillium’s Senior Vice President and Chief Operating Officer reported open-market sales of company common stock. On December 12, 2025, the executive sold 23,804 shares of Equillium common stock at a price of $1.34 per share. On December 15, 2025, an additional 11,900 shares were sold at $1.31 per share.

Following these transactions, the reporting person beneficially owned 91,444 shares of Equillium common stock in direct ownership. The filing notes that the reported sales were effected under a Rule 10b5-1 trading plan adopted by the reporting person on August 27, 2025, which is a pre-arranged plan for trading company stock.

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).

X

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^*

Zedelmayer Christine

(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)
	Sr. Vice President and COO

3. Date of Earliest Transaction (Month/Day/Year)
12/12/2025

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
Common Stock	12/12/2025		S(1)		23,804	D	$1.34	103,344	D
Common Stock	12/15/2025		S(1)		11,900	D	$1.31	91,444	D

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

Explanation of Responses:

1. The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 27, 2025.

	/s/ Daniel M. Bradbury, Attorney-in-Fact	12/15/2025
	** 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 insider stock transactions did Equillium (EQ) report in this filing?

The filing reports that a Senior Vice President and COO of Equillium sold 23,804 shares of common stock on December 12, 2025 at $1.34 per share, and 11,900 shares on December 15, 2025 at $1.31 per share.

Who conducted the transactions reported for Equillium (EQ)?

The transactions were conducted by a reporting person who is an Officer of Equillium, serving as Senior Vice President and Chief Operating Officer, according to the relationship section.

How many Equillium (EQ) shares does the insider own after these sales?

After the reported sales, the reporting person beneficially owned 91,444 shares of Equillium common stock, held with direct ownership.

Were the Equillium (EQ) insider sales made under a Rule 10b5-1 trading plan?

Yes. The explanation states that the sale reported was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 27, 2025.

On what dates did the Equillium (EQ) insider stock sales occur?

The reported sales of Equillium common stock occurred on December 12, 2025 and December 15, 2025, as shown in the non-derivative securities table.

What type of securities were involved in the Equillium (EQ) insider transactions?

The transactions involved Equillium common stock listed in Table I as non-derivative securities acquired, disposed of, or beneficially owned. No derivative securities are reported in Table II.