Director Carlo Calabria Acquires 1,051 Arqit Quantum Shares Through RSU Vesting

This Form 4 filing reports that Carlo Calabria, a director of Arqit Quantum Inc. (ARQQ), acquired 1,051 ordinary shares through the vesting and conversion of restricted stock units (RSUs) on April 1, 2026. The transactions involved four separate RSU grants with different vesting schedules. The first grant of 50 RSUs vested quarterly starting April 2026, two grants of 250 RSUs each vest quarterly through 2027, and a larger grant of 501 RSUs vested partially on April 1, 2026 with the remainder vesting quarterly through 2028. Following these transactions, Calabria's total direct ownership increased to 109,224 ordinary shares. The filing notes that as a foreign private issuer, Arqit Quantum's transactions are exempt from certain Section 16 provisions of the Securities Exchange Act.