FORM 4 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 that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES 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

(Print or Type Responses)

1. Name and Address of Reporting Person * Ahearn Matthew Fraser 2. Issuer Name and Ticker or Trading Symbol SHOULDER INNOVATIONS, INC. [SI] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chief Operating Officer (Last) (First) (Middle) C/O SHOULDER INNOVATIONS, INC., 1535 STEELE AVENUE SW, SUITE B 3. Date of Earliest Transaction (Month/Day/Year) 04/20/2026 (Street) GRAND RAPIDS, MI 49507 4. If Amendment, Date 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 (City) (State) (Zip) 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 04/20/2026 M 7,421 A $2.4804 272,522(1) D Common Stock 04/20/2026 M 14,243 A $2.862 286,765 D

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
	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 control number.		SEC 1474 (9-02)

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 Underlying Securities (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 of Derivative Security: 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

Stock Option

$2.4804

04/20/2026

M

7,421

(2)

05/09/2033

Common Stock

7,421

$ 0

8,864

D

Stock Option

$2.862

04/20/2026

M

14,243

(3)

04/23/2035

Common Stock

14,243

$ 0

42,731

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Ahearn Matthew Fraser C/O SHOULDER INNOVATIONS, INC. 1535 STEELE AVENUE SW, SUITE B GRAND RAPIDS, MI 49507	X		Chief Operating Officer

Signatures

/s/ Jeffrey Points, as Attorney-in-Fact		04/21/2026
**Signature of Reporting Person		Date

Explanation of Responses:

*	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).
(1)	Includes the following shares received without consideration as in-kind distributions: (i) 39,404 shares from Genesis Investment Holdings; (ii) 1,572 shares from cultivate(MD) Capital Accelerator Fund, L.P.; (iii) 4,400 shares from Cultivate MD Capital Fund I, LLC; and (iv) 3,869 shares from Cultivate MD Capital Fund II, LP. In prior reports, the reporting person reported beneficial ownership of 215,856 shares of Shoulder Innovations common stock held directly.
(2)	The stock option vested as to one-fourth of the underlying shares on April 19, 2024, and the remaining shares vest in 36 equal increments on the last day of each calendar month thereafter.
(3)	The stock option vested as to one-fourth of the underlying shares on April 1, 2026, and the remaining shares vest in 12 equal increments on the last day of each fiscal quarter beginning on June 30, 2026.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure. Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.