STOCK TITAN

Director Clay B. Siegall doubles Shattuck Labs (STTK) holdings with warrant exercise

Filing Impact
(Moderate)
Filing Sentiment
(Neutral)
Form Type
4

Rhea-AI Filing Summary

Shattuck Labs director Clay B. Siegall increased his direct stake by exercising warrants for common stock. On May 22, 2026, he acquired 128,054 shares of common stock at an exercise price of $1.0846 per share through the exercise of warrants.

These warrants were originally issued in a private placement under an August 4, 2025 securities purchase agreement, where he bought 128,054 shares of common stock with accompanying warrants at a combined price of $0.8677 per share and warrant. Following the latest transactions, Siegall directly holds 256,108 common shares, with the exercised warrants position reduced to zero.

Positive

  • None.

Negative

  • None.
Insider SIEGALL CLAY B
Role null
Type Security Shares Price Value
Exercise Warrants (Right to Buy) 128,054 $0.00 --
Grant/Award Common Stock 128,054 $1.0846 $139K
Holdings After Transaction: Warrants (Right to Buy) — 0 shares (Direct, null); Common Stock — 256,108 shares (Direct, null)
Footnotes (1)
  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. 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.
Common shares acquired 128,054 shares Acquired on May 22, 2026 via warrant exercise
Exercise price $1.0846 per share Conversion or exercise price of warrants
Shares held after transaction 256,108 shares Total direct common stock ownership post-transaction
Warrants exercised 128,054 warrants Derivative securities converted into common stock
Original private placement price $0.8677 per unit Combined price per share and accompanying warrant in 2025 placement
securities purchase agreement financial
"the Issuer entered into a securities purchase agreement (the "Purchase Agreement") with certain accredited investors"
A securities purchase agreement is a written contract between a buyer and a seller outlining the terms for buying or selling financial assets such as stocks or bonds. It specifies details like the price, quantity, and conditions of the transaction, similar to a shopping list with agreed-upon terms. For investors, it provides clarity and legal protection when transferring ownership of these financial instruments.
private placement financial
"the Issuer in a private placement, which closed on August 25, 2025, issued and sold"
A private placement is a way for companies to raise money by selling securities directly to a small group of investors instead of through a public offering. This process is often quicker and less regulated, making it similar to offering a special, exclusive investment opportunity to select individuals or institutions. For investors, it can provide access to unique investment options that are not available on public markets.
Warrants financial
"accompanying warrants (the "Warrants") to purchase up to an aggregate of 128,054 shares"
Warrants are special documents that give you the right to buy a company's stock at a set price before a certain date. They are often used as a way for companies to attract investors or raise money, and their value can increase if the company's stock price goes up.
Phase 1 clinical trial medical
"the Issuer's Phase 1 clinical trial of SL-325, including receptor occupancy and safety data"
A phase 1 clinical trial is the first stage of testing a new drug or treatment in people, typically involving a small group to assess safety, how the body handles the treatment, and appropriate dosing. For investors, phase 1 results are an early risk check — like a test drive that can reveal fatal flaws or promising signals — and they often cause big changes in a drug’s perceived value and the company’s prospects.
exercise or conversion of derivative security financial
"transaction code description: Exercise or conversion of derivative security"
SEC Form 4
FORM 4UNITED 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*
SIEGALL CLAY B

(Last)(First)(Middle)
C/O SHATTUCK LABS, INC.
500 W. 5TH STREET, SUITE 1200

(Street)
AUSTIN TEXAS 78701

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
Shattuck Labs, Inc. [ STTK ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
XDirector10% Owner
Officer (give title below)Other (specify below)
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
05/22/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

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)
CodeVAmount(A) or (D)Price
Common Stock05/22/2026A128,054A$1.0846256,108D
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)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Warrants (Right to Buy)$1.084605/22/2026M128,054 (2) (2)Common Stock128,054(1)0D
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. Siegall05/27/2026
** Signature of Reporting PersonDate
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.
* Form 4: SEC 1474 (03-26)

FAQ

What did Shattuck Labs (STTK) director Clay B. Siegall report in this Form 4?

Clay B. Siegall reported acquiring 128,054 Shattuck Labs common shares. He obtained these shares on May 22, 2026 by exercising previously issued warrants, bringing his direct holdings to 256,108 common shares after the transactions disclosed.

How many Shattuck Labs (STTK) shares does Clay B. Siegall own after this filing?

After the reported transactions, Clay B. Siegall directly owns 256,108 shares. This reflects the addition of 128,054 common shares acquired via warrant exercise on May 22, 2026, doubling his earlier 128,054-share stake from the prior private placement.

What was the exercise price for the Shattuck Labs (STTK) warrants in this Form 4?

The exercised warrants carried a conversion or exercise price of $1.0846 per share. Siegall used these warrants to acquire 128,054 common shares at that price, with the derivative position reduced to zero following the exercise.

How were the Shattuck Labs (STTK) warrants originally issued to Clay B. Siegall?

The warrants came from an August 4, 2025 securities purchase agreement. In that private placement, Shattuck Labs sold Siegall 128,054 common shares plus accompanying warrants at a combined price of $0.8677 per share and warrant, closing on August 25, 2025.

Does this Shattuck Labs (STTK) Form 4 show any insider share sales?

No, the Form 4 does not report any sales of Shattuck Labs shares. It shows only acquisitions: a grant/award of 128,054 common shares tied to warrant exercise and the exercise of 128,054 warrants, with no open-market or other dispositions.

What happens to Clay B. Siegall’s Shattuck Labs (STTK) warrants after this transaction?

The reported warrant position drops to zero after the exercise. Siegall exercised 128,054 warrants into 128,054 common shares at an exercise price of $1.0846, leaving no remaining warrants shown in this filing’s derivative summary.