ArcLight CTC Holdings, L.P. - Jun 14, 2021 Form 4 Insider Report for ArcLight Clean Transition Corp. (PTRA)

Role: 10%+ Owner
Signature: /s/ ArcLight CTC Holdings, L.P. By: ACTC Holdings GP, LLC, its General Partner /s/ Daniel R. Revers
Stock symbol: PTRA
Transactions as of: Jun 14, 2021
Transactions value $: $0
Form type: 4
Date filed: 6/16/2021, 09:25 PM

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	PTRA	Common Stock	Conversion of derivative security		+6.8M			6.8M	Jun 14, 2021	Direct	F1, F2, F3
transaction	PTRA	Common Stock	Other		-428	-0.01%		6.8M	Jun 14, 2021	Direct	F1, F2, F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	PTRA	Class B Ordinary Shares	Conversion of derivative security		-6.8M	-100%		0	Jun 14, 2021	Common Stock	6.8M		Direct	F1, F2, F3, F4
transaction	PTRA	Warrants	Other		+7.55M			7.55M	Jun 14, 2021	Common Stock	7.55M		Direct	F1, F4

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

ArcLight CTC Holdings, L.P. is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may continue.

Explanation of Responses:

Id	Content
F1	6,797,072 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"). Daniel R. Revers has voting and investment discretion with respect to the securities held by the Sponsor, 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 and Mr. Revers is 200 Clarendon Street, 55th Floor, Boston, MA 02116.
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 consummation of the Business Combination, 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.
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, Sponsor will own less than 10% of the outstanding common stock of New Proterra.
F4	In connection with the consummation of the Business Combination, 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.