* | Based on the information provided by Altair Engineering Inc. (the “Company”) to the Reporting Persons (as defined below), on September 30, 2024 (the “Event Date”), there were 59,517,279 shares of the Company’s Class A common stock, $0.0001 par value per share (the “Class A Common Stock”) outstanding. George J. Christ (“Mr. Christ”) is the Trustee of the Christ Revocable Trust dated May 8, 2015 (the “Christ Trust”), and the Manager of GC Investments, LLC (the “GC LLC” and, collectively with Mr. Christ and the Christ Trust, the “Reporting Persons”). Mr. Christ is also the Co-Trustee of The Dana Christ Irrevocable Trust Dated May 8, 2015 (the “Dana Trust”) and the Co-Trustee of The Lauren Christ Irrevocable Trust Dated May 8, 2015 (the “Lauren Trust”). As of the Event Date, the Reporting Persons may be deemed to beneficially own an aggregate of 9,450,684 shares of Class A Common Stock. The number of shares of Class A Common Stock reported above consists of (i) 4,481,778 shares of Class A Common Stock issuable upon conversion of 4,481,778 shares of the Company’s Class B common stock, $0.0001 par value per share (the “Class B Common Stock”), of the Company held by the Christ Trust, (ii) 4,044,004 shares of Class A Common Stock issuable upon conversion of 4,044,004 shares of Class B Common Stock held by the GC LLC, (iii) 400,000 shares of Class A Common Stock held by the GC LLC, (iv) 149,954 shares of Class A Common Stock held by the Christ Trust, (v) 187,475 shares of Class A Common Stock held by the Dana Trust and (vi) 187,475 shares of Class A Common Stock held by the Lauren Trust. The rights of the holders of Class A Common Stock and Class B Common Stock are identical, except with respect to voting and conversion rights. Each share of Class A Common Stock is entitled to one vote per share and each share of Class B Common Stock is entitled to ten votes per share. Each share of Class B Common Stock is immediately convertible, at the option of the Reporting Persons, 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 the Company’s Registration Statement filed with the Securities and Exchange Commission on Form S-1 (File No. 333-220710) for a description of the conversion rights. Thus, as of the Event Date, for purposes of Rule 13d-3 under the Securities Exchange Act of 1934, as amended, the Reporting Persons may be deemed to beneficially own 13.9% of the shares of Class A Common Stock issued and outstanding. The percentage was obtained by dividing (a) the number of shares of Class A Common Stock beneficially owned by the Reporting Persons as set forth in Row 9 by (b) the sum of (i) 59,517,279 shares of Class A Common Stock outstanding as of the Event Date and (ii) the 8,525,782 shares of Class A Common Stock issuable upon conversion of the Class B Common Stock. |