[Form 4] Shattuck Labs, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Insider purchase reported: Clay B. Siegall, a director of Shattuck Labs, Inc. (STTK), participated in a private placement that closed on August 25, 2025, acquiring 128,054 shares of common stock and accompanying warrants to buy up to 128,054 additional shares. The combined price for one share plus its accompanying warrant was $0.8677. The warrants have an exercise price of $1.0846 and are exercisable from issuance until 30 days after the company publicly announces certain Phase 1 SL-325 trial data and the planned Phase 2 design.

Positive

• Director participation in financing (128,054 shares) demonstrates insider alignment with the company's financing round
• Warrants exercisable upon clinical milestone announcement aligns potential equity upside with concrete trial data disclosure

Negative

• Warrants have a higher exercise price ($1.0846) than the combined purchase price per share-plus-warrant ($0.8677), requiring future value appreciation to realize gains
• Exercisability is contingent on specific clinical disclosures, which may delay or limit the ability to exercise the warrants

Insights

Securities Analyst

TL;DR: A director bought equity and warrants in a private placement at modest prices, aligning ownership with potential clinical milestones.

The reporting shows a direct acquisition of 128,054 common shares and matching warrants at a combined purchase price of $0.8677 per share-plus-warrant. Warrants carry a $1.0846 exercise price and are exercisable until a defined post-clinical-data announcement window. This transaction increases the director's direct equity stake and ties warrant exercisability to clinical progress, which links potential insider participation to product development catalysts.

Corporate Governance Expert

TL;DR: Director participation in a private placement is disclosed properly; terms restrict warrant exercise to specific trial disclosures.

The Form 4 discloses compliance with Section 16 reporting and notes purchase under a securities purchase agreement dated August 4, 2025, with a close on August 25, 2025. The filing identifies the director explicitly and shows direct ownership following the transaction. The warrant exercisability condition is clearly tied to public disclosure of Phase 1 SL-325 data and Phase 2 design, which is a defined milestone-based condition rather than a time-only expiration.

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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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^*

SIEGALL CLAY B

(Last) (First) (Middle)

C/O SHATTUCK LABS, INC.

500 W. 5TH STREET, SUITE 1200

(Street)

AUSTIN TX 78701

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Shattuck Labs, Inc. [ STTK ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
08/25/2025

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	08/25/2025		A(1)		128,054	A	$0.8677(1)	128,054	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
Warrants (Right to Buy)	$1.0846	08/25/2025		A(1)		128,054		(2)	(2)	Common Stock	128,054	(1)	128,054	D

Explanation of Responses:

1. On August 4, 2025, the Issuer entered into a securities purchase agreement (the "Purchase Agreement") with certain accredited investors, including the Reporting Person. Pursuant to the terms of the Purchase Agreement, the Issuer in a private placement, which closed on August 25, 2025, issued and sold to the Reporting Person 128,054 shares of the Issuer's common stock and accompanying warrants (the "Warrants") to purchase up to an aggregate of 128,054 shares of the Issuer's common stock at a combined price per share and accompanying Warrant of $0.8677.

2. The Warrants are exercisable at any time on or after the original issuance date until the 30th day following the date on which the data from the single ascending dose and multiple ascending dose portions of the Issuer's Phase 1 clinical trial of SL-325, including receptor occupancy and safety data, and the design of the planned Phase 2 clinical trial(s) have been announced publicly.

	/s/ Andrew R. Neill, Attorney-in-Fact for Clay B. Siegall	08/27/2025
	** 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.
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FAQ

What did Clay B. Siegall purchase in the STTK Form 4?

The filing shows Mr. Siegall acquired 128,054 common shares and accompanying warrants to purchase up to 128,054 shares in a private placement.

What price did the STTK private placement use?

The combined price per share plus accompanying warrant was $0.8677.

What is the warrant exercise price reported in the STTK Form 4?

The warrants have an exercise price of $1.0846 per share.

When can the warrants be exercised?

Warrants are exercisable from issuance until 30 days after public announcement of specified Phase 1 SL-325 data and the planned Phase 2 trial design.

When was the transaction completed?

The private placement closed and the acquisition was reported on 08/25/2025.