X0202 SCHEDULE 13D/A 0001420106 XXXXXXXX LIVE 1 Common Stock, $0.001 par value per share 08/05/2026 false 0001699350 82537J108 Shoulder Innovations, Inc.

1535 Steele Avenue SW Suite B Grand Rapids MI 49507

Gilde Healthcare Holding B.V. 31 30 219 2565 Stadsplateau 36 Utrecht P7 P7 3521 AZ 0001420106 N Gilde Healthcare Holding B.V. WC N P7 0 2212207 0 2212207 2212207 N 10.7 OO Y Gilde Healthcare V Management B.V. AF N P7 0 2212207 0 2212207 2212207 N 10.7 OO Y Cooperatieve Gilde Healthcare V U.A. AF N P7 0 2212207 0 2212207 2212207 N 10.7 OO Y Manapouri B.V. AF N P7 0 2212207 0 2212207 2212207 N 10.7 OO Y Martemanshurk B.V. AF N P7 0 2212207 0 2212207 2212207 N 10.7 OO Common Stock, $0.001 par value per share Shoulder Innovations, Inc. 1535 Steele Avenue SW Suite B Grand Rapids MI 49507 This Amendment No. 1 to Schedule 13D ("Amendment No. 1") amends and supplements the Schedule 13D filed on August 5, 2025 (as amended, the "Schedule 13D") relating to the Common stock, par value $0.001 per share (the "Common Stock"), of Shoulder Innovations, Inc. Information reported in the Schedule 13D remains in effect except to the extent that it is amended, restated or superseded by information contained in this Amendment No. 1. Capitalized terms used but not defined herein have the meanings ascribed to them in the Schedule 13D. Item 5(a) of the Schedule 13D is hereby amended and restated as follows: According to the Issuer's Quarterly Report on Form 10-K filed with the Securities and Exchange Commission on May 13, 2026, as of May 6, 2026, there were 20,738,226 shares of the Issuer's Common Stock outstanding. Gilde Healthcare is the record holder of an aggregate of 2,212,207 shares of Common Stock, which represents beneficial ownership of approximately 10.7% of the outstanding shares of Common Stock. GHCVM, as the manager of Gilde Healthcare, has the power to vote and dispose of securities held by Gilde Healthcare and may be deemed to beneficially own the securities held of record by Gilde Healthcare. GHCVM is owned by GHH. The managing partners of GHH are Manapouri B.V. and Martemanshurk B.V. As a result, each of the Reporting Persons may beneficially own an aggregate of 2,212,207 shares of Common Stock, or approximately 10.7% of the outstanding Common Stock. Item 5(c) of the Schedule 13D is hereby amended and supplemented by adding the following: The following transactions were effected by the Reporting Persons during the past 60 days. On July 30, 2026, 28,245 shares of Common Stock were sold at a weighted average price per share of $23.36, in multiple trades ranging from $23.00 to $23.73 per share. On July 31, 2026, 20,034 shares of Common Stock were sold at a weighted average price per share of $22.73, in multiple trades ranging from $22.60 to $23.00 per share. On August 3, 2026, 10,751 shares of Common Stock were sold at a weighted average price per share of $22.71, in multiple trades ranging from $22.60 to $23.05 per share. On August 4, 2026, 99,812 shares of Common Stock were sold at a weighted average price per share of $22.77, in multiple trades ranging from $22.60 to $23.04 per share. On August 5, 2026, 7,338 shares of Common Stock were sold at a weighted average price per share of $22.64, in multiple trades ranging from $22.60 to $23.00 per share. On August 6, 2026, 2,095 shares of Common Stock were sold at a price of $22.60 per share. Gilde Healthcare Holding B.V. /s/ Edwin de Graaf 08/07/2026 Gilde Healthcare V Management B.V. /s/ Edwin de Graaf 08/07/2026 Cooperatieve Gilde Healthcare V U.A. /s/ Edwin de Graaf 08/07/2026 Manapouri B.V. /s/ Edwin de Graaf 08/07/2026 Martemanshurk B.V. /s/ Pieter van der Meer 08/07/2026