X0206 3/A 2019-09-16 2019-09-18 1 0001701732 Altair Engineering Inc. ALTR 0001788469 Siudara Andrea C/O ALTAIR ENGINEERING INC. 1820 E. BIG BEAVER ROAD TROY MI 48083 0 1 0 0 Chief Information Officer Exhibit List Exhibit 24 - Power of Attorney This amendment to the original Form 3 filed September 18, 2019 is being filed to correct the spelling of the Reporting Person's last name and ensure that this form is tied to the corrected spelling. /s/ Raoul Maitra, attorney in fact for Andrea Siudara 2019-09-20