Form: 4

Statement of changes in beneficial ownership of securities

August 5, 2025

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
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X
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*
LSV Associates II, LLC

(Last) (First) (Middle)
420 BOYLSTON ST.
SUITE 602

(Street)
BOSTON MA 02116

(City) (State) (Zip)
2. Issuer Name and Ticker or Trading Symbol
SHOULDER INNOVATIONS, INC. [ SI ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director 10% Owner
Officer (give title below) X Other (specify below)
Former 10% Owner
3. Date of Earliest Transaction (Month/Day/Year)
08/01/2025
4. If Amendment, Date of Original Filed (Month/Day/Year)
6. Individual or Joint/Group Filing (Check Applicable Line)
Form filed by One Reporting Person
X 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 08/01/2025 C 1,618,470 A (1) 1,618,470 I See Footnotes(2)(3)
Common Stock 08/01/2025 P 266,666 A $15 1,885,136 I See Footnotes(2)(3)
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
Series C Convertible Preferred Stock (1) 08/01/2025 C 20,930,233 (1) (1) Common Stock 1,096,971 (1) 0 I See Footnotes(2)(4)
Series D Convertible Preferred Stock (1) 08/01/2025 C 9,950,208 (1) (1) Common Stock 521,499 (1) 0 I See Footnotes(2)(4)
1. Name and Address of Reporting Person*
LSV Associates II, LLC

(Last) (First) (Middle)
420 BOYLSTON ST.
SUITE 602

(Street)
BOSTON MA 02116

(City) (State) (Zip)
1. Name and Address of Reporting Person*
Lightstone Ventures II, L.P.

(Last) (First) (Middle)
420 BOYLSTON ST.
SUITE 602

(Street)
BOSTON MA 02116

(City) (State) (Zip)
1. Name and Address of Reporting Person*
Lightstone Ventures II (A), L.P.

(Last) (First) (Middle)
420 BOYLSTON ST.
SUITE 602

(Street)
BOSTON MA 02116

(City) (State) (Zip)
1. Name and Address of Reporting Person*
Plain Henry A JR

(Last) (First) (Middle)
420 BOYLSTON ST.
SUITE 602

(Street)
BOSTON MA 02116

(City) (State) (Zip)
1. Name and Address of Reporting Person*
George Jean

(Last) (First) (Middle)
420 BOYLSTON ST.
SUITE 602

(Street)
BOSTON MA 02116

(City) (State) (Zip)
Explanation of Responses:
1. Immediately prior to the closing of the Issuer's initial public offering, the shares of preferred stock of the Issuer automatically converted into shares of Common Stock on a one-for-0.052410901 basis.
2. LSV Associates II, LLC is the general partner of Lightstone Ventures II, L.P. ("LSV II") and Lightstone Ventures II (A), L.P. ("LSV II (A)") and has sole voting and dispositive power with respect to the shares held by LSV II and LSV II (A). The reporting person is a managing director of LSV Associates II, LLC, and shares voting and dispositive power with respect to the shares held of record 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). 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.
3. Following the transactions reported in this Form 4, (i) 1,781,479 shares of Common Stock are held by LSV II and (ii) 103,657 shares of Common Stock are held by LSV II (A).
4. 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 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 LSV II (A).
Lightstone Ventures II, L.P., By: LSV Associates II, LLC, its general partner, By: /s/ Henry Plain, Managing Director 08/05/2025
Lightstone Ventures II (A), L.P., By: LSV Associates II, LLC, its general partner, By: /s/ Henry Plain, Managing Director 08/05/2025
LSV Associates II, LLC By: /s/ Henry Plain, Managing Director 08/05/2025
/s/ Henry Plain 08/05/2025
/s/ Jean George 08/05/2025
** 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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