Magnus Halle Form 3 Filing for GH Research PLC Share Options and Ownership

This Form 3 filing reports the initial beneficial ownership of Magnus Halle, Managing Director of GH Research PLC (GHRS). Halle owns 118,354 ordinary shares directly. Additionally, he holds three separate share option grants: 17,500 options exercisable at $0.025 expiring April 27, 2030; 150,000 options exercisable at $0.025 expiring November 25, 2031; and 50,000 options exercisable at $0.025 expiring May 16, 2032. The options have vesting schedules with 25% initial vesting followed by equal monthly installments over three years. The filing includes a power of attorney executed on February 23, 2026, authorizing designated individuals to file Forms 3, 4, and 5 on Halle's behalf. This is a standard initial ownership disclosure for an officer of the company.