X0306 4 2022-02-15 0001701732 Altair Engineering Inc. ALTR 0001720312 Schramm Uwe C/O ALTAIR ENGINEERING INC. 1820 E. BIG BEAVER RD. TROY MI 48083 1 Chief Vision Officer Class A Common Stock 2022-02-15 4 A 0 2850 0 A 41115 D Class A Common Stock 2022-03-14 4 S 0 128 59.963 D 40765 D Stock Option (Right to Buy) 61.79 2022-02-15 4 A 0 8500 0 A 2032-02-15 Class A Common Stock 8500 8500 D On February 15, 2022, the Reporting Person was granted 2,850 Class A Common Stock restricted stock units, which vest in 4 equal annual installments commencing February 15, 2023. Includes 7,562 Class A Common Stock restricted stock units that are unvested. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $59.96 to $60.12 per share, inclusive. The reporting person undertakes to provide to Altair Engineering Inc., any security holder of Altair Engineering Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth herein. Includes 7,200 Class A Common Stock restricted stock units that are unvested. On February 15, 2022, the Reporting Person was granted 8,500 Class A Common Stock options, the options vest in 4 equal annual installments commencing February 15, 2023. /s/ Raoul Maitra, attorney-in-fact for Uwe Schramm 2022-03-15