X0206 3 2017-10-31 0 0001701732 Altair Engineering Inc. ALTR 0001720314 Scapa James Ralph C/O ALTAIR ENGINEERING INC. 1820 E. BIG BEAVER ROAD TROY MI 1 1 1 0 Chief Executive Officer Stock Option (right to buy) 0.64 2020-07-01 Class A Common Stock 1734996 D Stock Option (right to buy) 5.18 2027-06-09 Class A Common Stock 120000 D Class B Common Stock 0.00 Class A Common Stock 12651416 I By James R. Scapa Declaration of Trust dated March 5, 1987 Class B Common Stock 0.00 Class A Common Stock 7424004 I By JRS Investments, LLC The options vested upon grant. The option is currently fully vested. The options vest in 4 equal annual installments commencing June 9, 2018. Each share of Class B common stock is immediately convertible, at the option of the shareholder, into one share of Class A common stock and shall automatically convert into Class A common stock upon the occurrence of certain events. Please see Altair Engineering Inc. Registration Statement filed with the Securities and Exchange Commission on Form S-1 (File No. 333-220710) for a description of the conversion rights. The reporting person serves as Trustee. Reporting person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose. Reporting person serves as Manager. Reporting person disclaims beneficial ownership of these securities except to the extent of his pecuniary interest therein, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose. Exhibit List Exhibit 24 - Power of Attorney /s/ James R. Scapa 2017-10-31