X0206 3 2017-10-31 0 0001701732 Altair Engineering Inc. ALTR 0001720807 Christ George J C/O ALTAIR ENGINEERING INC. 1820 E. BIG BEAVER ROAD TROY MI 48083 0 0 1 0 Class B Common Stock 0.00 Class A Common Stock 9346728 I By Christ Revocable Trust dated May 8, 2015 Class B Common Stock 0.00 Class A Common Stock 6424004 I By GC Investments, LLC 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/ George J. Christ 2017-10-31