Was the Cullinan Therapeutics (CGEM) insider sale related to compensation or tax obligations?

Yes. The Form 4 footnote states the sale of 3,742 shares was to cover personal income tax obligations arising when restricted stock units vested, indicating a tax-driven transaction rather than a purely discretionary portfolio trade.

Cullinan CLO sells 3,742 shares for tax obligations

Cullinan Therapeutics Chief Legal Officer sells shares for taxes.

Filing Impact

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Filing Sentiment

(Negative)How Sentiment works

Sentiment and the balance of points

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Rhea-AI Filing Summary

Cullinan Therapeutics Chief Legal Officer sells shares for taxes. Jacquelyn L. Sumer executed an open-market sale of 3,742 shares of Cullinan Therapeutics common stock at $13.62 per share on February 20, 2026 to cover personal income tax obligations upon vesting of restricted stock units. After this transaction, she directly holds 131,690 shares.

Insider Trade Summary

Net Seller: 3,742 shares

Net Sell 1 txn

Insider SUMER JACQUELYN L

Role Chief Legal Officer

Sold 3,742 shs ($51K)

Type	Security	Shares	Price	Value
Sale	Common Stock	3,742	$13.62	$51K

Holdings After Transaction: Common Stock — 131,690 shares (Direct)

Footnotes (1)

F1. Sale of shares to cover personal income tax obligations upon vesting of restricted stock units.

FAQ

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What insider transaction did Cullinan Therapeutics (CGEM) report in this Form 4?

Cullinan Therapeutics reported that Chief Legal Officer Jacquelyn L. Sumer sold 3,742 shares of common stock in an open-market transaction at $13.62 per share, primarily to cover personal income tax obligations related to vesting restricted stock units.

Who is the insider involved in the latest Cullinan Therapeutics (CGEM) Form 4 filing?

The insider is Jacquelyn L. Sumer, Chief Legal Officer of Cullinan Therapeutics. She reported an open-market sale of 3,742 shares of common stock conducted on February 20, 2026, connected to tax obligations from vesting restricted stock units.

How many Cullinan Therapeutics (CGEM) shares did the insider sell and at what price?

Jacquelyn L. Sumer sold 3,742 shares of Cullinan Therapeutics common stock at a price of $13.62 per share. The transaction was categorized as an open-market sale and linked to covering personal income tax obligations on vested restricted stock units.

How many Cullinan Therapeutics (CGEM) shares does the insider hold after the Form 4 transaction?

Following the reported sale, Chief Legal Officer Jacquelyn L. Sumer directly holds 131,690 shares of Cullinan Therapeutics common stock. This post-transaction balance reflects her remaining direct ownership after selling 3,742 shares for tax-related purposes.

What transaction code is used in the Cullinan Therapeutics (CGEM) Form 4 filing and what does it mean?

The Form 4 uses transaction code “S,” indicating a sale in an open market or private transaction. In this case, the 3,742-share sale at $13.62 per share was further explained as being executed to satisfy personal income tax obligations.

AI-generated analysis. How Rhea-AI works. Not financial advice.

Form 4 Insider Transactions: What Each Field Means →

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Accepted by SEC EDGAR 02/23/2026 - 05:00 PM EST

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^*

SUMER JACQUELYN L

(Last)

(First)

(Middle)

C/O CULLINAN THERAPEUTICS, INC.

ONE MAIN STREET, SUITE 1350

(Street)

CAMBRIDGE

02142

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
Cullinan Therapeutics, Inc. [ CGEM ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
02/20/2026

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	02/20/2026		S⁽¹⁾		3,742	D	$13.62	131,690	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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. Sale of shares to cover personal income tax obligations upon vesting of restricted stock units.

	/s/ Jacquelyn Sumer	02/23/2026
	** 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).
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.

Source: View Original Filing on SEC EDGAR