Schedule 13D/A Filing for Ironwood Pharmaceuticals Inc.

This filing, Amendment No. 4 to the Schedule 13D, details changes in beneficial ownership of Ironwood Pharmaceuticals, Inc. Class A Common Stock by Sarissa Capital Management LP and Dr. Alexander J. Denner. As of March 19, 2026, Sarissa Capital Management LP beneficially owns 9,188,635 shares, representing 5.6% of the issuer's outstanding shares. Dr. Denner may be deemed to beneficially own 9,444,944 shares, approximately 5.8% of the outstanding shares. The filing reports that on March 17, 2026, Sarissa Capital Management LP sold a total of 6,730,800 shares in open market transactions. Additionally, Dr. Denner was granted 4,451 shares in his capacity as a director on the same date. The principal business address for the Reporting Persons is now listed as c/o Sarissa Capital Management LP, 500 West Putnam Ave, Suite 400, Greenwich, CT 06830.