# EDGAR Filing Document

**Accession Number:** 0001706610
**File Stem:** 0001641172-25-021635
**Filing Date:** 2025-7
**Character Count:** 11785
**Document Hash:** 0fd24a7c614418638b64d4655e6ecdbc
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001641172-25-021635.hdr.sgml**: 20250730

**ACCESSION NUMBER**: 0001641172-25-021635

**CONFORMED SUBMISSION TYPE**: 3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250730

**FILED AS OF DATE**: 20250730

**DATE AS OF CHANGE**: 20250730

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** George Jean
- **CENTRAL INDEX KEY:** 0001291804

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42771
- **FILM NUMBER:** 251169044

**MAIL ADDRESS:**
- **STREET 1:** 3270 ALPINE RD.
- **CITY:** PORTOLA VALLEY
- **STATE:** CA
- **ZIP:** 94028
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Plain Henry A JR
- **CENTRAL INDEX KEY:** 0001384286

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42771
- **FILM NUMBER:** 251169045

**MAIL ADDRESS:**
- **STREET 1:** 3270 ALPINE RD.
- **CITY:** PORTOLA VALLEY
- **STATE:** CA
- **ZIP:** 94028
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** LSV Associates II, LLC
- **CENTRAL INDEX KEY:** 0001818388

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42771
- **FILM NUMBER:** 251169048

**BUSINESS ADDRESS:**
- **STREET 1:** 3270 ALPINE RD.
- **CITY:** PORTOLA VALLEY
- **STATE:** CA
- **ZIP:** 94028
- **BUSINESS PHONE:** 650-388-3676

**MAIL ADDRESS:**
- **STREET 1:** 3270 ALPINE RD.
- **CITY:** PORTOLA VALLEY
- **STATE:** CA
- **ZIP:** 94028
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Lightstone Ventures II, L.P.
- **CENTRAL INDEX KEY:** 0001699565

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42771
- **FILM NUMBER:** 251169047

**BUSINESS ADDRESS:**
- **STREET 1:** 3270 ALPINE RD.
- **CITY:** PORTOLA VALLEY
- **STATE:** CA
- **ZIP:** 94028
- **BUSINESS PHONE:** 650-388-3676

**MAIL ADDRESS:**
- **STREET 1:** 3270 ALPINE RD.
- **CITY:** PORTOLA VALLEY
- **STATE:** CA
- **ZIP:** 94028
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Lightstone Ventures II (A), L.P.
- **CENTRAL INDEX KEY:** 0001706610

**ORGANIZATION NAME:**
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42771
- **FILM NUMBER:** 251169046

**BUSINESS ADDRESS:**
- **STREET 1:** 3270 ALPINE RD.
- **CITY:** PORTOLA VALLEY
- **STATE:** CA
- **ZIP:** 94028
- **BUSINESS PHONE:** 650-388-3676

**MAIL ADDRESS:**
- **STREET 1:** 3270 ALPINE RD.
- **CITY:** PORTOLA VALLEY
- **STATE:** CA
- **ZIP:** 94028
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** SHOULDER INNOVATIONS, INC.
- **CENTRAL INDEX KEY:** 0001699350
- **STANDARD INDUSTRIAL CLASSIFICATION:** SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
- **ORGANIZATION NAME:** 08 Industrial Applications and Services
- **EIN:** 270538764
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 13827 PORT SHELDON STREET
- **CITY:** HOLLAND
- **STATE:** MI
- **ZIP:** 49424
- **BUSINESS PHONE:** 616-566-0286

**MAIL ADDRESS:**
- **STREET 1:** 13827 PORT SHELDON STREET
- **CITY:** HOLLAND
- **STATE:** MI
- **ZIP:** 49424

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

## FORM 3

### INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>LSV Associates II, LLC<br><sub>(Last) (First) (Middle)</sub><br>420 BOYLSTON ST.<br>SUITE 602<br><sub>(Street)</sub><br>BOSTON, MA 02116<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>SHOULDER INNOVATIONS, INC. [ SI ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2025-07-30 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Lightstone Ventures II, L.P.<br><sub>(Last) (First) (Middle)</sub><br>420 BOYLSTON ST.<br>SUITE 602<br><sub>(Street)</sub><br>BOSTON, MA 02116<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>SHOULDER INNOVATIONS, INC. [ SI ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2025-07-30 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Lightstone Ventures II (A), L.P.<br><sub>(Last) (First) (Middle)</sub><br>420 BOYLSTON ST.<br>SUITE 602<br><sub>(Street)</sub><br>BOSTON, MA 02116<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>SHOULDER INNOVATIONS, INC. [ SI ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2025-07-30 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Plain Henry A JR<br><sub>(Last) (First) (Middle)</sub><br>420 BOYLSTON ST.<br>SUITE 602<br><sub>(Street)</sub><br>BOSTON, MA 02116<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>SHOULDER INNOVATIONS, INC. [ SI ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2025-07-30 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>George Jean<br><sub>(Last) (First) (Middle)</sub><br>420 BOYLSTON ST.<br>SUITE 602<br><sub>(Street)</sub><br>BOSTON, MA 02116<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>SHOULDER INNOVATIONS, INC. [ SI ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2025-07-30 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities Beneficially Owned

---

|  |  |  |  |
| --- | --- | --- | --- |
| 1. Title of Security | 2. Amount of Securities Beneficially Owned | 3. Ownership Form | 4. Nature of Indirect Beneficial Ownership |

---

## Table II - Derivative Securities Beneficially Owned

---

|  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 3. Title and Amount of Underlying Securities | 3. Title and Amount of Underlying Securities | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| Series C Convertible Preferred Stock | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 1096971 | <sup>(1)</sup> | I | See Footnotes<sup>(2)(3)</sup> |
| Series D Convertible Preferred Stock | <sup>(1)</sup> | <sup>(1)</sup> | Common Stock | 521499 | <sup>(1)</sup> | I | See Footnotes<sup>(2)(3)</sup> |

---

### Footnotes:

(1) Immediately prior to the closing of the Issuer's initial public offering, the shares of preferred stock of the Issuer will automatically convert into shares of Common Stock on a one-for-0.052410901 basis. The shares of preferred stock have no expiration date.

(2) Consists of (i) 1,036,638 shares of Common Stock underlying Series C Preferred Stock, and 492,833 shares of Common Stock underlying Series D Preferred Stock held by Lightstone Ventures II, L.P. ("LSV II"); and (ii) 60,333 shares of Common Stock underlying Series C Preferred Stock and 28,666 shares of Common Stock underlying Series D Preferred Stock held by Lightstone Ventures II (A), L.P. ("LSV II (A)"). LSV Associates II, LLC is the general partner of LSV II and LSV II (A) and has sole voting and dispositive power with respect to the shares held by LSV II and LSV II (A). Jean George, Michael A. Carusi and Henry A. Plain, Jr. are the managing directors of LSV Associates II, LLC, and share voting and dispositive power with respect to the shares held of record by LSV II and LSV II (A).

(3) Mr. Carusi is a director of the Issuer and files separate Section 16 reports. Each of the reporting persons disclaims beneficial ownership of such shares except to the extent of his, her or its respective pecuniary interest therein.

**Signature:** Lightstone Ventures II, L.P., By: LSV Associates II, LLC, its general partner, By: /s/ Henry Plain, Managing Director  
**Date:** 2025-07-30

**Signature:** Lightstone Ventures II (A), L.P., By: LSV Associates II, LLC, its general partner, By: /s/ Henry Plain, Managing Director  
**Date:** 2025-07-30

**Signature:** LSV Associates II, LLC By: /s/ Henry Plain, Managing Director  
**Date:** 2025-07-30

**Signature:** /s/ Henry Plain  
**Date:** 2025-07-30

**Signature:** /s/ Jean George  
**Date:** 2025-07-30

### Remarks:

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.**