Daniel R. Revers - 14 Jun 2021 Form 4 Insider Report for ArcLight Clean Transition Corp.

Footnote F1

7,397,072 shares of common stock, par value $0.0001 ("New Proterra Common Stock"), of New Proterra (as defined below) are held directly by ArcLight CTC Holdings, L.P. a Delaware limited liability partnership (the "Sponsor") and 600,000 shares of New Proterra Common Stock are held directly by ArcLight CTC Investors, LLC, a Delaware limited liability company ("ArcLight Investor"). Daniel R. Revers has voting and investment discretion with respect to the securities held by each of the Sponsor and ArcLight Investor, and thus may be deemed to have beneficial ownership of such securities. Mr. Revers expressly disclaims any such beneficial ownership of such securities, except to the extent of his individual pecuniary interests therein. The business address of Sponsor, ArcLight Investor and Mr. Revers is 200 Clarendon Street, 55th Floor, Boston, MA, 02116.

Footnote F2

Pursuant to the Agreement and Plan of Merger, dated January 11, 2021, by and among ArcLight Clean Transition Corp., a Cayman Islands exempted company (the "Company"), Phoenix Merger Sub, Inc., a Delaware corporation, and Proterra Inc, a Delaware corporation ("Proterra"), the parties effected a business combination transaction ("Business Combination") on June 14, 2021. In connection with the Business Combination, the Company domesticated as a Delaware corporation (the "Domestication") and changed its name to "Proterra Inc" ("New Proterra"). In connection with the Domestication, 6,797,500 of Sponsor's Class B ordinary shares, par value $0.0001, of the Company, which were previously convertible into Class A ordinary shares, par value $0.0001, of the Company ("Class A ordinary shares") converted into shares of common stock, par value $0.0001, of New Proterra ("New Proterra Common Stock") simultaneously with the closing of the Business Combination.

Footnote F3

Continuation of Footnote 2: Sponsor then forfeited and surrendered for no consideration 428 shares of New Proterra Common Stock. After giving effect to this transaction, Daniel R. Revers will own less than 10% of the outstanding common stock of New Proterra. In connection with the consummation of the Business Combination and pursuant to the subscription agreement between ArcLight Investor and the Company, ArcLight Investor acquired 600,000 shares of New Proterra Common Stock for an aggregate purchase price of $6,000,000.

Footnote F4

In connection with the Domestication, 7,550,000 of the private placement warrants of the Company ("ArcLight Private Placement Warrants") held by Sponsor, which previously entitled Sponsor to purchase one Class A Ordinary Share at a price of $11.50 per whole share at any time commencing on the later of one year from the closing of the Company's initial public offering or 30 days after the completion of an initial business combination of the Company, were converted into private placement warrants of Proterra (each a "New Proterra Private Placement Warrant") simultaneously with the closing of the Business Combination, with each whole New Proterra Private Placement Warrant entitling the holder thereof to the right to purchase one share of New Proterra Common Stock.