X0609 4 2026-10-05 0 0001699350 SHOULDER INNOVATIONS, INC. SI 0001215243 BUCKMAN PAUL false C/O SHOULDER INNOVATIONS, INC. 1535 STEELE AVENUE SW, SUITE B GRAND RAPIDS MI 49507 1 0 0 0 0 Common Stock 2026-10-05 4 A 0 1275 19.60 A 65025 D Represents an award of restricted stock units ("RSUs") received in lieu of cash retainer fees, which were fully vested as of the grant date. Each RSU represents a contingent right to receive one share of the Issuer's Common Stock and has no expiration date. The Reporting Person voluntarily elected to defer receipt of the Common Stock issuable upon settlement of the RSUs until the Reporting Person's departure from the Board of Directors. /s/ Jeffrey Points, as Attorney-in-Fact 2026-10-06