Equillium (EQ) COO exercises options, sells 185,937 pre-planned shares

Rhea-AI Filing Summary

Equillium, Inc. senior vice president and COO Christine Zedelmayer reported an exercise-and-sell set of transactions in company common stock. On February 19, 2026, she exercised options to acquire a total of 185,937 shares of common stock at prices of $0.785 and $0.73 per share.

On the same date, she sold the same 185,937 shares in open-market transactions at average prices of about $1.78 per share. After these trades, she directly held 91,444 shares of Equillium common stock. The filing notes that the sales were made under a Rule 10b5-1 trading plan adopted on August 27, 2025, indicating they were pre-arranged rather than timed discretionarily.

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
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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).

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)
02/19/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)
02/23/2026

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	02/19/2026		M		109,375	A	$0.785	200,819	D
Common Stock	02/19/2026		S(1)		109,375	D	$1.7814	91,444	D
Common Stock	02/19/2026		M		76,562	A	$0.73	168,006	D
Common Stock	02/19/2026		S(1)		76,562	D	$1.7406	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.

Remarks:

Due solely to a scrivener's error, the number of shares beneficially owned was misreported in Table I, Column 5 of a prior Form 4 filed with the Securities and Exchange Commission on February 23, 2026, which overreported the amount of beneficially owned shares by 100,000 shares.

	/s/ Christine Zedelmayer	03/10/2026
	** 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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FAQ

What insider transactions did Equillium (EQ) COO Christine Zedelmayer report?

Christine Zedelmayer reported exercising options for 185,937 Equillium shares and selling the same number on February 19, 2026. The trades converted option holdings into cash while leaving her with 91,444 shares of common stock held directly afterward.

How many Equillium (EQ) shares did the COO sell and at what prices?

She sold 185,937 Equillium common shares on February 19, 2026 at average prices of about $1.7814 and $1.7406 per share. These sales followed option exercises at much lower prices, turning derivative awards into realized value.

Did Equillium (EQ) COO Zedelmayer’s trades occur under a Rule 10b5-1 plan?

Yes. The filing states the sale transactions were executed under a Rule 10b5-1 trading plan adopted on August 27, 2025. Such plans pre-schedule trades, suggesting these sales were planned rather than based on short-term market developments.

How many Equillium (EQ) shares does the COO hold after these transactions?

After exercising options and selling the acquired shares, Christine Zedelmayer directly holds 91,444 Equillium common shares. This figure reflects her remaining equity position as reported, following the February 19, 2026 exercise-and-sell activity.

What was the structure of the Equillium (EQ) COO’s option exercises and sales?

She exercised options to acquire 109,375 shares at $0.785 and 76,562 shares at $0.73, then sold identical amounts at about $1.7814 and $1.7406. This pattern represents typical exercise-and-sell transactions converting options into cash.