# EDGAR Filing Document

**Accession Number:** 0001055951
**File Stem:** 0000947871-25-000841
**Filing Date:** 2025-9
**Character Count:** 21046
**Document Hash:** 9e8c98cb97e46ceabaa3a3828fd446f2
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000947871-25-000841.hdr.sgml**: 20250902

**ACCESSION NUMBER**: 0000947871-25-000841

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13D

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20250902

**DATE AS OF CHANGE**: 20250902

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Shattuck Labs, Inc.
- **CENTRAL INDEX KEY:** 0001680367
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 812575858
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-91760
- **FILM NUMBER:** 251287630

**BUSINESS ADDRESS:**
- **STREET 1:** 500 W. 5TH STREET
- **CITY:** AUSTIN
- **STATE:** TX
- **ZIP:** 78701
- **BUSINESS PHONE:** 512-900-4690

**MAIL ADDRESS:**
- **STREET 1:** 500 W. 5TH STREET
- **CITY:** AUSTIN
- **STATE:** TX
- **ZIP:** 78701
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** ORBIMED ADVISORS LLC
- **CENTRAL INDEX KEY:** 0001055951

**ORGANIZATION NAME:**
- **EIN:** 133976876
- **STATE OF INCORPORATION:** DE

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D

**BUSINESS ADDRESS:**
- **STREET 1:** 601 LEXINGTON AVENUE
- **STREET 2:** 54TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10022
- **BUSINESS PHONE:** (212) 739-6400

**MAIL ADDRESS:**
- **STREET 1:** 601 LEXINGTON AVENUE
- **STREET 2:** 54TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10022

## Exhibit 99.1

**<u>Exhibit 1</u>**

JOINT FILING AGREEMENT

The undersigned hereby agree that the Statement on Schedule 13D, dated August 25, 2025, with respect to the common stock of Shattuck Labs, Inc., is filed on behalf of each of us pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended. Each of the undersigned agrees to be responsible for the timely filing of this Statement, and for the completeness and accuracy of the information concerning itself contained therein. This Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the 2<sup>nd</sup> day of September 2025.

---

| | |
|:---|:---|
| **ORBIMED ADVISORS LLC** | **ORBIMED ADVISORS LLC** |
| By: | <u>/s/ Carl L. Gordon</u> |
|  | Name: Carl L. Gordon |
|  | Title: Member |
| **ORBIMED CAPITAL GP IX LLC** | **ORBIMED CAPITAL GP IX LLC** |
| By: | ORBIMED ADVISORS LLC, its managing member |
| By: | <u>/s/ Carl L. Gordon</u> |
|  | Name: Carl L. Gordon |
|  | Title: Member of OrbiMed Advisors LLC |
| **ORBIMED GENESIS GP LLC** | **ORBIMED GENESIS GP LLC** |
| By: | ORBIMED ADVISORS LLC, its managing member |
| By: | <u>/s/ Carl L. Gordon</u> |
|  | Name: Carl L. Gordon |
|  | Title: Member of OrbiMed Advisors LLC |

---

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**Shattuck Labs, Inc.**

*(Name of Issuer)*

**Common Stock, par value $0.0001 per share**

*(Title of Class of Securities)*

**82024L103**

*(CUSIP Number)*

**OrbiMed Advisors LLC**<br>601 Lexington Avenue<br>54th Floor<br>New York NY 10022<br>(212) 739-6400

*(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)*

**08/25/2025**

*(Date of Event Which Requires Filing of this Statement)*

| **CUSIP No.** | **82024L103** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**ORBIMED ADVISORS LLC** | Name of reporting person<br>**ORBIMED ADVISORS LLC** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**6306127.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**6306127.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**6306127.00** | Aggregate amount beneficially owned by each reporting person<br>**6306127.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**9.99%** | Percent of class represented by amount in Row (11)<br>**9.99%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IA** | Type of Reporting Person (See Instructions)<br>**IA** | |

---

| **CUSIP No.** | **82024L103** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**OrbiMed Capital GP IX LLC** | Name of reporting person<br>**OrbiMed Capital GP IX LLC** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**5255106.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**5255106.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**5255106.00** | Aggregate amount beneficially owned by each reporting person<br>**5255106.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**8.32%** | Percent of class represented by amount in Row (11)<br>**8.32%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**OO** | Type of Reporting Person (See Instructions)<br>**OO** | |

---

| **CUSIP No.** | **82024L103** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**OrbiMed Genesis GP LLC** | Name of reporting person<br>**OrbiMed Genesis GP LLC** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**AF** | Source of funds (See Instructions)<br>**AF** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**DELAWARE** | Citizenship or place of organization<br>**DELAWARE** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**1051021.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**1051021.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**1051021.00** | Aggregate amount beneficially owned by each reporting person<br>**1051021.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**1.67%** | Percent of class represented by amount in Row (11)<br>**1.67%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**OO** | Type of Reporting Person (See Instructions)<br>**OO** | |

---

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
Common Stock, par value $0.0001 per share

**(b) Name of Issuer:**
Shattuck Labs, Inc.

**(c) Address of Issuer's Principal Executive Offices:**
500 W 5th St., Austin, TX, 78701

**Item 4. Purpose of Transaction**

This Statement on Schedule 13D relates to the acquisition of Shares by the
Reporting Persons. The Shares acquired by the Reporting Persons were acquiredfor the purpose of making an investment in the Issuer and not with the intentionof acquiring control of the Issuer's business on behalf of the Reporting
Persons' respective advisory clients.

      The Reporting Persons from time to time intend to review their investmentin the Issuer on the basis of various factors, including the Issuer's business,financial condition, results of operations and prospects, general economic andindustry conditions, the securities markets in general and those for the
Issuer's Shares in particular, as well as other developments and otherinvestment opportunities. Based upon such review, the Reporting Persons willtake such actions in the future as the Reporting Persons may deem appropriate inlight of the circumstances existing from time to time. If the Reporting Personsbelieve that further investment in the Issuer is attractive, whether because ofthe market price of Shares or otherwise, they may acquire Shares or othersecurities of the Issuer either in the open market or in privately negotiatedtransactions. Similarly, depending on market and other factors, the Reporting
Persons may determine to dispose of some or all of the Shares currently owned bythe Reporting Persons or otherwise acquired by the Reporting Persons either inthe open market or in privately negotiated transactions.

      Except as set forth in this Schedule 13D, the Reporting Persons have notformulated any plans or proposals which relate to or would result in: (a) theacquisition by any person of additional securities of the Issuer or thedisposition of securities of the Issuer, (b) an extraordinary corporatetransaction, such as a merger, reorganization or liquidation, involving the
Issuer or any of its subsidiaries, (c) a sale or transfer of a material amountof the assets of the Issuer or any of its subsidiaries, (d) any change in thepresent Board of Directors or management of the Issuer, including any plans orproposals to change the number or term of directors or to fill any existingvacancies on the board, (e) any material change in the Issuer's capitalizationor dividend policy of the Issuer, (f) any other material change in the Issuer'sbusiness or corporate structure, (g) any change in the Issuer's charter orbylaws or other instrument corresponding thereto or other action which mayimpede the acquisition of control of the Issuer by any person, (h) causing aclass of the Issuer's securities to be deregistered or delisted from a nationalsecurities exchange or to cease to be authorized to be quoted in an inter-dealerquotation system of a registered national securities association, (i) a class ofequity securities of the Issuer becoming eligible for termination ofregistration pursuant to Section 12(g)(4) of the Act or (j) any action similarto any of those enumerated above.

**Item 5. Interest in Securities of the Issuer**

**(a)**
The following disclosure is based upon (i) 47,903,215 outstanding Shares, as set forth in the Issuer's Current Report on Form 8-K filed with the SEC on August 14, 2025 plus (ii) 15,225,158 Shares issued by the Issuer in the PIPE, as set forth in the Issuer's Current Report on Form 8-K filed with the SEC on August 5, 2025.

As of the date of this filing, OPI IX holds 5,255,106 Shares constituting approximately 9.99% of the issued and outstanding Shares, Pre-Funded Warrants to purchase 10,111,384 Shares and Common Warrants to purchase 15,366,490 Shares. The Pre-Funded Warrants are not exercisable due to the Blocker. OrbiMed GP is the general partner of OPI IX, pursuant to the terms of the limited partnership agreement of OPI IX, and OrbiMed Advisors is the managing member of OrbiMed GP, pursuant to the terms of the limited liability company agreement of OrbiMed GP. As a result, OrbiMed Advisors and OrbiMed GP share power to direct the vote and disposition of the Shares held by OPI IX and may be deemed directly or indirectly, including by reason of their mutual affiliation, to be the beneficial owners of the Shares held by OPI IX. OrbiMed Advisors exercises this investment and voting power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the Shares held by OPI IX.

In addition, OrbiMed Advisors and OrbiMed GP, pursuant to their authority under the limited partnership agreement of OPI IX, caused OPI IX to enter into the agreements referred to in Items 3 and 6.

As of the date of this filing, Genesis holds 1,051,021 Shares constituting approximately 1.67% of the issued and outstanding Shares, Pre-Funded Warrants to purchase 2,022,277 Shares and Common Warrants to purchase 3,073,298 Shares. The Pre-Funded Warrants and Common Warrants are not presently exercisable due to the Blocker. OrbiMed Genesis is the general partner of Genesis, pursuant to the terms of the limited partnership agreement of Genesis, and OrbiMed Advisors is the managing member of OrbiMed Genesis, pursuant to the terms of the limited liability company agreement of OrbiMed Genesis. As a result, OrbiMed Advisors and OrbiMed Genesis share power to direct the vote and disposition of the Shares held by Genesis and may be deemed, directly or indirectly, including by reason of their mutual affiliation, to be the beneficial owners of the Shares held by Genesis. OrbiMed Advisors exercises this investment and voting power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the Shares held by Genesis.

In addition, OrbiMed Advisors and OrbiMed Genesis, pursuant to their authority under the limited partnership agreement of Genesis, caused Genesis to enter into the agreements referred to in Items 3 and 6.

**(b)**
Item 5(a) is incorporated by reference herein.

**(c)**
Except as disclosed in Item 3, the Reporting Persons have not effected any transactions during the past sixty (60) days in any Shares.

**Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.**

In addition to the relationships between the Reporting Persons described in Items 2 and 5 above, OrbiMed GP is the general partner of OPI IX, pursuant to the terms of the limited partnership agreement of OPI IX. Pursuant to this agreement and relationship, OrbiMed GP has discretionary investment management authority with respect to the assets of OPI IX. Such authority includes the power to vote and otherwise dispose of securities held by OPI IX. The number of outstanding Shares of the Issuer attributable to OPI IX is 5,255,106 Shares, which amount excludes Pre-Funded Warrants to purchase 10,111,384 Shares and Common Warrants to purchase 15,366,490 Shares. OrbiMed GP, pursuant to its authority under the limited partnership agreement of OPI IX, may be considered to hold indirectly 5,255,106 Shares, which amount excludes the Warrants.

In addition to the relationships between the Reporting Persons described in Items 2 and 5 above, OrbiMed Genesis is the general partner of Genesis, pursuant to the terms of the limited partnership agreement of Genesis. Pursuant to this agreement and relationship, OrbiMed Genesis has discretionary investment management authority with respect to the assets of Genesis. Such authority includes the power to vote and otherwise dispose of securities held by Genesis. The number of outstanding Shares of the Issuer attributable to Genesis is 1,051,021 Shares, which amount excludes Pre-Funded Warrants to purchase 2,022,277 Shares and Common Warrants to purchase 3,073,298 Shares. OrbiMed Genesis, pursuant to its authority under the limited partnership agreement of Genesis, may be considered to hold indirectly 1,051,021 Shares, which amount excludes the Warrants.

In addition to the relationships between the Reporting Persons described in Items 2 and 5 above, OrbiMed Advisors is the managing member of OrbiMed GP and OrbiMed Genesis, pursuant to the terms of the limited liability company agreements of OrbiMed GP and OrbiMed Genesis. Pursuant to these agreements and relationships, OrbiMed Advisors and OrbiMed GP have discretionary investment management authority with respect to the assets of OPI IX. OrbiMed Advisors and OrbiMed Genesis have discretionary investment management authority with respect to the assets of Genesis. Such authority includes the power of OrbiMed GP to vote and otherwise dispose of securities held by OPI IX and the power of OrbiMed Genesis to vote and otherwise dispose of the securities held by Genesis. The number of outstanding Shares attributable to OPI IX is 5,255,106 Shares and the number of Shares attributed to Genesis is 1,051,021 Shares, which in each case, excludes the Warrants held by OPI IX and Genesis.

Mona Ashiya ("Ashiya"), a member of OrbiMed Advisors, is a member of the Board of Directors of the Issuer and, accordingly, OrbiMed Advisors and OrbiMed GP may have the ability to affect and influence control of the Issuer. From time to time, Ashiya may receive stock options or other awards of equity-based compensation pursuant to the Issuer's compensation arrangements for non-employee directors. Pursuant to an agreement with OrbiMed Advisors and OrbiMed GP, Ashiya is obligated to transfer any securities issued under any such stock options or other awards, or the economic benefit thereof, to OrbiMed Advisors and OrbiMed GP, which will in turn ensure that such securities or economic benefits are provided to OPI IX.

Registration Rights Agreement

In connection with the PIPE, the Issuer entered into a registration rights agreement (the "Registration Rights Agreement") with the PIPE Investors, including OPI IX and Genesis, pursuant to which the Issuer agreed that, within 30 calendar days after the closing of the PIPE, the Issuer will file with the SEC (at the Issuer's sole cost and expense) a registration statement registering the resale of the Shares purchased in the PIPE.

The foregoing descriptions of the Registration Rights Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Registration Rights Agreement, which is filed as Exhibit 2 and incorporated herein by reference.

### SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** ORBIMED ADVISORS LLC

**Signature:** /s/ Carl L. Gordon

**Name/Title:** Carl L. Gordon/Member

**Date:** 09/02/2025

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** OrbiMed Capital GP IX LLC

**Signature:** /s/ Carl L. Gordon

**Name/Title:** Carl L. Gordon/Member of OrbiMed Advisors LLC

**Date:** 09/02/2025

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** OrbiMed Genesis GP LLC

**Signature:** /s/ Carl L. Gordon

**Name/Title:** Carl L. Gordon/Member of OrbiMed Advisors LLC

**Date:** 09/02/2025