X0508 4 2025-12-11 0 0001699350 SHOULDER INNOVATIONS, INC. SI 0002070664 Ball Robert Joseph C/O SHOULDER INNOVATIONS, INC. 1535 STEELE AVENUE SW, SUITE B GRAND RAPIDS MI 49507 1 1 0 0 CEO & Executive Chairman 0 Common Stock 2025-12-11 4 P 0 3300 14.8285 A 114557 D Common Stock 2025-12-12 4 P 0 3900 14.8911 A 118457 D The price reported in Column 4 is a weighted average purchase price. The shares of Common Stock were purchased in multiple transactions at prices ranging from $14.56 to $15.16, inclusive. The Reporting Person undertakes to provide upon request by the staff of the Securities & Exchange Commission, the Issuer or any security holder of the Issuer, full information regarding the number of shares of Common Stock purchased at each separate price within the range set forth herein. The price reported in Column 4 is a weighted average purchase price. The shares of Common Stock were purchased in multiple transactions at prices ranging from $14.60 to $15.26, inclusive. The Reporting Person undertakes to provide upon request by the staff of the Securities & Exchange Commission, the Issuer or any security holder of the Issuer, full information regarding the number of shares of Common Stock purchased at each separate price within the range set forth herein. /s/ Jeffrey Points, as Attorney-in-Fact 2025-12-15