As filed with the Securities and Exchange Commission on April 7, 2021

No. 333-252674

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549
________________________________________

AMENDMENT NO. 1
TO
FORM S-4
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
________________________________________

ArcLight Clean Transition Corp.*
(Exact name of registrant as specified in its charter)

________________________________________

Cayman Islands*

 

6770

 

98-1551379

(State or other jurisdiction of
incorporation or organization)

 

(Primary Standard Industrial
Classification Code Number)

 

(I.R.S. Employer
Identification No.)

________________________________________

200 Clarendon Street, 55th Floor
Boston, Massachusetts 02116
617
-531-6300
(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

________________________________________

John F. Erhard
Chief Executive Officer
200 Clarendon Street, 55
th Floor
Boston, Massachusetts 02116
617
-531-6300
(Name, address, including zip code, and telephone number, including area code, of agent for service)

________________________________________

Copies of all communications, including communications sent to agent for service, should be sent to:

Christian O. Nagler
James S. Rowe
Kirkland & Ellis LLP
601 Lexington Avenue
New York, New York 10022
(212) 446
-4800

 

Mark Gerstein
Ryan Maierson
Latham & Watkins LLP
330 North Wabash Avenue,
Suite 2800
Chicago, Illinois 60611
(312) 876
-7700

 

Dawn H. Belt
Per B. Chilstrom
Fenwick & West LLP
801 California Street
Mountain View, California 94041
(650) 988
-8500

________________________________________

Approximate date of commencement of proposed sale to the public: As soon as practicable after this Registration Statement becomes effective.

If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box. £

If this Form is filed to registered additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. £

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. £

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

 

Large accelerated filer

 

£

 

Accelerated Filer

 

£

   

Non-accelerated filer

 

S

 

Smaller reporting company

 

S

           

Emerging growth company

 

S

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. £

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer) £

Exchange Act Rule 14d-l(d) (Cross-Border Third-Party Tender Offer) £

 

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CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered

 

Amount
to be
Registered
(4)

 

Proposed
Maximum
Offering
Price
Per Unit

 

Proposed
Maximum
Aggregate
Offering
Price
(1)

 

Amount of
Registration
Fee

New Proterra Common Stock(1)

 

237,575,422

 

$

23.45

(5)

 

$

5,571,143,645

 

$

607,811.77

(8)

New Proterra Common Stock(2)

 

21,425,000

 

$

11.50

(6)

 

$

246,387,500

 

$

26,880.88

(8)

Warrants to purchase New Proterra Common Stock(3)

 

21,425,000

 

$

7.61

(7)

 

$

163,044,250

 

$

17,788.13

(8)

Total

 

280,425,422

 

 

 

 

 

 

   

$

652,480.78

(8)(9)

____________

(1)      The number of shares of common stock of New Proterra (as defined below) being registered represents (i) 25,000,000 Class A ordinary shares underlying units issued in the initial public offering of ArcLight Clean Transition Corp., a Cayman Islands exempted company (“ArcLight”), (ii) 2,750,000 Class A ordinary shares underlying units issued pursuant to the partial exercise by the underwriters of their over-allotment option in connection with ArcLight’s initial public offering, (iii) 6,937,500 Class B ordinary shares held by ArcLight’s initial shareholders and (iv) up to 202,887,922 shares of common stock of New Proterra (the “New Proterra Common Stock”) that may be issued to the Proterra Holders (as defined in the accompanying proxy statement/prospectus) in connection with the Business Combination as described in the proxy statement/prospectus forming part of this registration statement (the “proxy statement/prospectus”).

(2)      Represents shares of New Proterra Common Stock to be issued upon the exercise of (i) 13,875,000 warrants to purchase Class A ordinary shares underlying units issued in ArcLight’s initial public offering (“public warrants”) and (ii) 7,550,000 warrants to purchase Class A ordinary shares underlying units issued in a private placement simultaneously with the closing of ArcLight’s initial public offering (“private placement warrants” and, together with the public warrants, the “ArcLight warrants”). The ArcLight warrants will convert into warrants to acquire shares of New Proterra Common Stock.

(3)      The number of warrants to acquire shares of New Proterra Common Stock being registered represents (i) 13,875,000 public warrants and (ii) 7,550,000 private placement warrants.

(4)      Pursuant to Rule 416(a) of the Securities Act of 1933, as amended (the “Securities Act”), there are also being registered an indeterminable number of additional securities as may be issued to prevent dilution resulting from stock splits, stock dividends or similar transactions.

(5)      Estimated solely for the purpose of calculating the registration fee, based on the average of the high and low prices of the Class A ordinary shares of ArcLight on the Nasdaq Capital Market on January 28, 2021 ($23.45 per Class A ordinary share). This calculation is in accordance with Rule 457(f)(1) of the Securities Act.

(6)      Represents the exercise price of the warrants.

(7)      Estimated solely for the purpose of calculating the registration fee, based on the average of the high and low prices of the ArcLight public warrants on the Nasdaq Capital Market on January 28, 2021 ($7.61 per warrant). This calculation is in accordance with Rule 457(f)(1) of the Securities Act.

(8)      Calculated by multiplying the proposed maximum aggregate offering price of securities to be registered by 0.0001091.

(9)      Registration fee has previously been paid.

*        Immediately prior to the consummation of the Business Combination (as defined in the accompanying proxy statement/prospectus), ArcLight intends to effect a deregistration under the Cayman Islands Companies Act (As Revised) and a domestication under Part XII of the Delaware General Corporation Law, pursuant to which ArcLight’s jurisdiction of incorporation will be changed from the Cayman Islands to the State of Delaware (the “Domestication”). All securities being registered will be issued by the continuing entity following the Domestication, which continuing entity will be renamed “Proterra Inc” following the Effective Time. As used herein, “New Proterra” refers to ArcLight after giving effect to the Business Combination.

The registrant hereby amends this Registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until this Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

 

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The information in this preliminary proxy statement/prospectus is not complete and may be changed. The registrant may not sell the securities described in this preliminary proxy statement/prospectus until the registration statement filed with the Securities and Exchange Commission is declared effective. This preliminary proxy statement/prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

PRELIMINARY — SUBJECT TO COMPLETION, DATED APRIL 7, 2021

PROXY STATEMENT FOR
EXTRAORDINARY GENERAL MEETING OF ARCLIGHT CLEAN TRANSITION CORP.
PROSPECTUS FOR
259,
000,422 SHARES OF COMMON STOCK AND 21,425,000 WARRANTS

____________________

The board of directors of ArcLight Clean Transition Corp., a Cayman Islands exempted company (“ArcLight”), has unanimously approved the transactions (collectively, the “Business Combination”) contemplated by that certain Agreement and Plan of Merger, dated January 11, 2021 (as it may be amended, supplemented or otherwise modified from time to time, the “Merger Agreement”), by and among ArcLight, Phoenix Merger Sub, Inc., a Delaware corporation and a wholly-owned direct subsidiary of ArcLight (“Phoenix Merger Sub”), and Proterra Inc, a Delaware corporation (“Proterra”), a copy of which is attached to this proxy statement/prospectus as Annex A, including the deregistration of ArcLight under the Cayman Islands Companies Act (As Revised) and the domestication under Part XII of the Delaware General Corporation Law, pursuant to which ArcLight’s jurisdiction of incorporation will be changed from the Cayman Islands to the State of Delaware (the “Domestication”). As described in this proxy statement/prospectus, ArcLight’s shareholders are being asked to consider a vote upon each of the Domestication and the Business Combination, among other items. As used in this proxy statement/prospectus, “New Proterra” refers to ArcLight (which, following the Effective Time, will change its name to “Proterra Inc”) after giving effect to the Business Combination.

In connection with the Domestication, on the Closing Date prior to the Effective Time (each as defined in the accompanying proxy statement/prospectus): (i) each issued and outstanding Class A ordinary share, par value $0.0001 per share (the “Class A ordinary shares”), of ArcLight will be converted, on a one-for-one basis, into duly authorized, validly issued, fully paid and nonassessable shares of common stock, par value $0.0001 per share, of New Proterra (the “New Proterra Common Stock”); (ii) each issued and outstanding Class B ordinary share, par value $0.0001 per share (the “Class B ordinary shares”), of ArcLight will automatically convert, on a one-for-one basis, into shares of New Proterra Common Stock, (iii) each issued and outstanding whole warrant to purchase Class A ordinary shares of ArcLight will automatically represent the right to purchase one share of New Proterra Common Stock at an exercise price of $11.50 per share on the terms and conditions set forth in the ArcLight warrant agreement; and (iv) the governing documents of ArcLight will be amended and restated and become the certificate of incorporation and the bylaws of New Proterra as described in this proxy statement/prospectus. In connection with clauses (i), (ii) and (iii) of this paragraph, each issued and outstanding unit of ArcLight that has not been previously separated into the underlying Class A ordinary shares of ArcLight and the underlying warrants of ArcLight prior to the Domestication will be cancelled and will entitle the holder thereof to one share of New Proterra Common Stock and one-half of one warrant, with such whole warrant representing the right to purchase one share of New Proterra Common Stock at an exercise price of $11.50 per share, on the terms and subject to the conditions set forth in the ArcLight warrant agreement.

On the Closing Date, promptly following the consummation of the Domestication, Phoenix Merger Sub will merge with and into Proterra (the “Merger”), with Proterra as the surviving company in the Merger and, after giving effect to the Merger, Proterra will be a wholly-owned subsidiary of ArcLight (the time that the Merger becomes effective being referred to as the “Effective Time”). In accordance with the terms and subject to the conditions of the Merger Agreement, at the Effective Time, (i) each share of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for 0.8925 shares of New Proterra Common Stock, (ii) each warrant and equity award of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for comparable warrants or equity awards that are exercisable for 0.8925 shares of New Proterra Common Stock, as applicable, and (iii) each outstanding secured convertible promissory note convertible into shares of Proterra stock (collectively, the “Convertible Notes”) that is not optionally converted immediately prior to the Effective Time will become convertible into shares of New Proterra Common Stock, in accordance with the terms of the Convertible Note.

It is anticipated that, upon completion of the Business Combination, (i) the Proterra Holders will own, collectively, approximately 68.6% of the outstanding New Proterra Common Stock, and (ii) ArcLight’s Initial Shareholders (as defined in the accompanying proxy statement/prospectus) will own approximately 2.6% of the outstanding New Proterra Common Stock, in each case, assuming that none of ArcLight’s outstanding public shares are redeemed in connection with the Business Combination, or approximately 77.8% and 2.9%, respectively, assuming that all of ArcLight’s outstanding public shares are redeemed in connection with the Business Combination. See “Business Combination Proposal — Ownership of New Proterra” for more details.

 

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This prospectus covers 259,000,422 shares of New Proterra Common Stock (including shares that are to be issued or may be issuable (i) upon exercise of the ArcLight warrants, (ii) upon exercise of vested, in-the-money equity awards, vested, out-of-the-money equity awards and unvested equity awards of Proterra, (ii) in exchange for shares of Proterra Common Stock, (iii) upon the conversion of the Convertible Notes of Proterra and (iv) upon the exercise of warrants of Proterra) and 21,425,000 warrants to acquire shares of New Proterra Common Stock to be issued in connection with the Business Combination. The number of shares of New Proterra Common Stock that this prospectus covers represents the maximum number of shares that may be issued to Proterra Holders, the maximum number of shares that may be issuable to holders of Convertible Notes if such Notes were converted at the Closing (as more fully described in this proxy statement/prospectus) and the maximum number of shares issued or issuable to the existing shareholders and warrant holders of ArcLight, in each case, in connection with the Business Combination.

ArcLight’s units, public shares and public warrants are currently listed on Nasdaq under the symbols “ACTCU,” “ACTC” and “ACTCW,” respectively. ArcLight will apply for listing, to be effective at the time of the Business Combination, of New Proterra Common Stock and warrants on Nasdaq under the proposed symbols “PTRA” and “PTRAW,” respectively. It is a condition of the consummation of the Business Combination that ArcLight receive confirmation from Nasdaq that New Proterra has been conditionally approved for listing on Nasdaq, but there can be no assurance such listing condition will be met or that ArcLight will obtain such confirmation from Nasdaq. If such listing condition is not met or if such confirmation is not obtained, the Business Combination will not be consummated unless the Nasdaq condition set forth in the Merger Agreement is waived by the applicable parties.

The accompanying proxy statement/prospectus provides shareholders of ArcLight with detailed information about the Business Combination and other matters to be considered at the extraordinary general meeting of ArcLight. We encourage you to read the entire accompanying proxy statement/prospectus, including the Annexes and other documents referred to therein, carefully and in their entirety. You should also carefully consider the risk factors described in “Risk Factors” beginning on page 28 of the accompanying proxy statement/prospectus.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES REGULATORY AGENCY HAS APPROVED OR DISAPPROVED THE TRANSACTIONS DESCRIBED IN THE ACCOMPANYING PROXY STATEMENT/PROSPECTUS, PASSED UPON THE MERITS OR FAIRNESS OF THE BUSINESS COMBINATION OR RELATED TRANSACTIONS OR PASSED UPON THE ADEQUACY OR ACCURACY OF THE DISCLOSURE IN THE ACCOMPANYING PROXY STATEMENT/PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY CONSTITUTES A CRIMINAL OFFENSE.

The accompanying proxy statement/prospectus is dated        , 2021, and
is first being mailed to ArcLight’s shareholders on or about        , 2021.

 

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ARCLIGHT CLEAN TRANSITION CORP.

200 Clarendon Street, 55th Floor
Boston, Massachusetts 02116

Dear ArcLight Clean Transition Corp. Shareholders:

You are cordially invited to attend the extraordinary general meeting (the “extraordinary general meeting”) of ArcLight Clean Transition Corp., a Cayman Islands exempted company (“ArcLight”), at        , on        , 2021, at the offices of Kirkland & Ellis LLP located at                , or at such other time, on such other date and at such other place to which the meeting may be adjourned. In the interest of public health, and due to the impact of the coronavirus (“COVID-19”), we are also planning for the meeting to be held virtually over the Internet, but the physical location of the meeting will remain at the location specified above for the purposes of our amended and restated memorandum and articles of association.

As further described in the accompanying proxy statement/prospectus, in connection with the Domestication, on the Closing Date prior to the Effective Time (as described below), among other things, (i) all of the outstanding shares of ArcLight will be converted into common stock of a new Delaware corporation and all of the outstanding ArcLight warrants will be converted into warrants to purchase common stock of a new Delaware corporation and (ii) the governing documents of ArcLight will be amended and restated. Following consummation of the Business Combination, ArcLight will change its name to “Proterra Inc”. As used in the accompanying proxy statement/prospectus, “New Proterra” refers to ArcLight after giving effect to the Business Combination.

At the extraordinary general meeting, ArcLight shareholders will be asked to consider and vote upon a proposal, which is referred to herein as the “Business Combination Proposal” to approve and adopt the Agreement and Plan of Merger, dated as of January 11, 2021 (as may be amended, supplemented or otherwise modified from time to time, the “Merger Agreement”), by and among ArcLight, Phoenix Merger Sub, Inc., a Delaware corporation and a wholly-owned direct subsidiary of ArcLight (“Phoenix Merger Sub”), and Proterra Inc, a Delaware corporation (“Proterra”), a copy of which is attached to the accompanying proxy statement/prospectus as Annex A, including the transactions contemplated thereby, and to vote upon a proposal to approve the Domestication, which is referred to herein a the “Domestication Proposal.”

As further described in the accompanying proxy statement/prospectus, subject to the terms and conditions of the Merger Agreement, the following transactions will occur:

(a)     On the Closing Date, prior to the Effective Time, ArcLight will change its jurisdiction of incorporation by deregistering as a Cayman Islands exempted company and continuing and domesticating as a corporation incorporated under the laws of the State of Delaware (the “Domestication”) (for further details, see “Proposal No. 2 — The Domestication Proposal”). Following consummation of the Business Combination, ArcLight will change its name to “Proterra Inc” (“New Proterra”).

(b)    Phoenix Merger Sub will merge with and into Proterra (the “Merger”), with Proterra as the surviving company in the Merger and, after giving effect to such Merger, Proterra shall be a wholly-owned subsidiary of ArcLight. In accordance with the terms and subject to the conditions of the Merger Agreement, at the Effective Time, (i) each share of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for 0.8925 shares of common stock, par value $0.0001 per share, of New Proterra (the “New Proterra Common Stock”), and (ii) each warrant and equity award of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for comparable warrants and equity awards that are exercisable for 0.8925 shares of New Proterra Common Stock, and (iii) each outstanding secured convertible promissory notes of Proterra (a “Convertible Note,” collectively the “Convertible Notes”) that is not optionally converted immediately prior to the Effective Time will become convertible into shares of New Proterra Common Stock, in accordance with the terms of the Convertible Note.

 

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In connection with the foregoing and concurrently with the execution of the Merger Agreement, ArcLight entered into Subscription Agreements (the “Subscription Agreements”) with certain investors, including certain affiliates of ArcLight (the “PIPE Investors”), pursuant to which the PIPE Investors have agreed to subscribe for and purchase, and ArcLight has agreed to issue and sell to the PIPE Investors, an aggregate of 41,500,000 shares New Proterra Common Stock at a price of $10.00 per share, for aggregate gross proceeds of $415,000,000, on the terms and subject to the conditions set forth in the Subscription Agreements (the “PIPE Financing”). The shares of New Proterra Common Stock to be issued pursuant to the Subscription Agreements have not been registered under the Securities Act of 1933, as amended (the “Securities Act”), in reliance upon the exemption provided in Section 4(a)(2) of the Securities Act. ArcLight has granted the PIPE Investors certain registration rights in connection with the PIPE Financing. The PIPE Financing is contingent upon, among other things, the substantially concurrent closing of the Business Combination.

In addition to the Business Combination Proposal and the Domestication Proposal, you will also be asked to consider and vote upon (a) four (4) separate proposals to approve material differences between ArcLight’s existing amended and restated memorandum and articles of association (the “Existing Governing Documents”) and the proposed new certificate of incorporation of New Proterra and the proposed new bylaws of New Proterra upon the Domestication, copies of which are attached to the accompanying proxy statement/prospectus as Annexes C and D, respectively, which are referred to herein collectively as the “Governing Documents Proposals,” (b) a proposal to approve, for purpose of complying with Nasdaq Listing Rule 5635, the issuance of New Proterra Common Stock in connection with the Business Combination and the PIPE Financing, which is referred to herein as the “Nasdaq Proposal,” (c) a proposal to approve and adopt the Proterra Inc 2021 Equity Incentive Plan, a copy of which is attached to the proxy statement/prospectus as Annex H, which is referred to herein as the “Equity Incentive Plan Proposal,” (d) a proposal to approve and adopt the Proterra Inc 2021 Employee Stock Purchase Plan, a copy of which is attached to the accompanying proxy statement/prospectus as Annex I, which is referred to herein as the “Employee Stock Purchase Plan Proposal,” and (e) a proposal to adjourn the extraordinary general meeting to a later date or dates to the extent necessary, which is referred to herein as the “Adjournment Proposal.”

The Business Combination will be consummated only if the Business Combination Proposal, the Domestication Proposal, the Governing Documents Proposals, the Nasdaq Proposal, the Equity Incentive Plan Proposal and the Employee Stock Purchase Plan Proposal (collectively, the “Condition Precedent Proposals”) are approved at the extraordinary general meeting. The Adjournment Proposal is not conditioned upon the approval of any other proposal. Each of these proposals is more fully described in the accompanying proxy statement/prospectus, which each shareholder is encouraged to read carefully and in its entirety.

The Adjournment Proposal provides for a vote to adjourn the extraordinary general meeting to a later date or dates (A) to the extent necessary to ensure that any required supplement or amendment to the accompanying proxy statement/prospectus is provided to ArcLight shareholders or, if as of the time for which the extraordinary general meeting is scheduled, there are insufficient ArcLight ordinary shares represented (either in person or by proxy) to constitute a quorum necessary to conduct business at the extraordinary general meeting, (B) in order to solicit additional proxies from ArcLight shareholders in favor of one or more of the proposals at the extraordinary general meeting or (C) if ArcLight shareholders redeem an amount of the public shares such that one of the conditions to consummate the Business Combination that the aggregate cash proceeds to be received by ArcLight from the trust account in connection with the Business Combination, together with the aggregate gross proceeds from the PIPE Financing, equal no less than $300,000,000 as a condition to ArcLight’s obligation to close or $350,000,000 as a condition to Proterra’s obligation to close (in each case, after deducting any amounts paid to ArcLight’s stockholders that exercise their redemption rights in connection with the Business Combination and net of unpaid transaction expenses incurred or subject to reimbursement by ArcLight) would not be satisfied at Closing (such aggregate proceeds, the “Aggregate Transaction Proceeds,” and such condition to the consummation of the Business Combination, the “Aggregate Transaction Proceeds Condition”).

In connection with the Business Combination, certain related agreements have been or will be entered into on or prior to the closing of the Business Combination, including the Subscription Agreements, the Amended and Restated Registration Rights Agreement, the Sponsor Support Agreement, the Sponsor Letter Agreement, Amendment No. 1 to the Sponsor Letter Agreement and the Proterra Stockholder Support Agreements (each as defined in the accompanying proxy statement/prospectus). See “Business Combination Proposal — Related Agreements” in the accompanying proxy statement/prospectus for more information.

 

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Pursuant to the Existing Governing Documents, a holder of ArcLight’s public shares (a “public shareholder”) may request that ArcLight redeem all or a portion of such public shares for cash if the Business Combination is consummated. In order to redeem public shares underlying units, holders of units must elect to separate their units into the underlying public shares and warrants prior to exercising redemption rights with respect to such public shares. Holders that hold their units in an account at a brokerage firm or bank must notify their broker or bank that they elect to separate the units into the underlying public shares and warrants, or if a holder holds units registered in its own name, the holder must contact Continental Stock Transfer & Trust Company (“Continental”), ArcLight’s transfer agent, directly and instruct it to do so. The redemption rights include the requirement that a holder must identify itself in writing as a beneficial holder and provide its legal name, phone number and address to Continental in order to validly redeem its shares. Public shareholders may elect to redeem their public shares even if they vote “for” the Business Combination Proposal. If the Business Combination is not consummated, the public shares will be returned to the respective holder, broker or bank. If the Business Combination is consummated, and if a public shareholder properly exercises its right to redeem all or a portion of the public shares that it holds and timely delivers its shares to Continental, ArcLight will redeem such public shares for a per-share price, payable in cash, equal to the pro rata portion of the trust account established at the consummation of ArcLight’s initial public offering, calculated as of two business days prior to the consummation of the Business Combination. For illustrative purposes, based on 26,290,616 shares subject to possible redemption as of December 31, 2020, this would have amounted to approximately $10.56 per issued and outstanding public share. If a public shareholder exercises its redemption rights in full, then it will be electing to exchange its public shares for cash and will no longer own public shares. The redemption will take place following the Domestication and, accordingly, it is shares of New Proterra Common Stock that will be redeemed immediately after consummation of the Business Combination. See “Extraordinary General Meeting of ArcLight — Redemption Rights” in the accompanying proxy statement/prospectus for a detailed description of the procedures to be followed if you wish to redeem your public shares for cash.

Notwithstanding the foregoing, a public shareholder, together with any affiliate of such public shareholder or any other person with whom such public shareholder is acting in concert or as a “group” (as defined in Section 13(d)(3) of the Securities Exchange Act of 1934, as amended (“Exchange Act”)), will be restricted from redeeming its public shares with respect to more than an aggregate of 15% of the public shares. Accordingly, if a public shareholder, alone or acting in concert or as a group, seeks to redeem more than 15% of the public shares, then any such shares in excess of that 15% limit would not be redeemed for cash.

The Initial Shareholders have, pursuant to the Sponsor Support Agreement (each as defined in the accompanying proxy statement/prospectus), agreed to, among other things, vote all of their ordinary shares in favor of the proposals being presented at the extraordinary general meeting and waive their anti-dilution rights with respect to their Class B ordinary shares in connection with the consummation of the Business Combination. Such shares will be excluded from the pro rata calculation used to determine the per-share redemption price. As of the date of the accompanying proxy statement/prospectus, the Initial Shareholders own 20.0% of the issued and outstanding ordinary shares. See “Business Combination Proposal — Related Agreements — Sponsor Support Agreement” in the accompanying proxy statement/prospectus for more information related to the Sponsor Letter Agreement.

The Merger Agreement is subject to the satisfaction or waiver of certain other closing conditions as described in the accompanying proxy statement/prospectus. There can be no assurance that the parties to the Merger Agreement would waive any such provision of the Merger Agreement. In addition, in no event will ArcLight redeem public shares in an amount that would cause New Proterra’s net tangible assets (as determined in accordance with Rule 3a51-1(g)(1) of the Exchange Act) to be less than $5,000,001 after giving effect to the transactions contemplated by the Merger Agreement and the PIPE Financing.

ArcLight is providing the accompanying proxy statement/prospectus and accompanying proxy card to ArcLight’s shareholders in connection with the solicitation of proxies to be voted at the extraordinary general meeting and at any adjournments of the extraordinary general meeting. Information about the extraordinary general meeting, the Business Combination and other related business to be considered by ArcLight’s shareholders at the extraordinary general meeting is included in the accompanying proxy statement/prospectus. Whether or not you plan to attend the extraordinary general meeting, all of ArcLight’s shareholders are urged to read the accompanying proxy statement/prospectus, including the Annexes and other documents referred to therein, carefully and in their entirety. You should also carefully consider the risk factors described inRisk Factorsbeginning on page 28 of the accompanying proxy statement/prospectus.

 

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After careful consideration, the board of directors of ArcLight has unanimously approved the Merger Agreement and the transactions contemplated thereby, including the Merger, and unanimously recommends that shareholders vote “FOR” the adoption of the Merger Agreement and approval of the transactions contemplated thereby, including the Merger, and “FOR” all other proposals presented to ArcLight’s shareholders in the accompanying proxy statement/prospectus. When you consider the recommendation of these proposals by the board of directors of ArcLight, you should keep in mind that ArcLight’s directors and officers have interests in the Business Combination that may conflict with your interests as a shareholder. See the section entitled “Business Combination Proposal — Interests of ArcLight’s Directors and Executive Officers in the Business Combination” in the accompanying proxy statement/prospectus for a further discussion of these considerations.

The approval of the Domestication Proposal requires a special resolution under Cayman Islands law, being the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter. The approval of each of the Business Combination Proposal, the Governing Documents Proposals (other than Proposal D), the Equity Incentive Plan Proposal, the Employee Stock Purchase Plan Proposal, the Nasdaq Proposal and the Adjournment Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

Your vote is very important.    Whether or not you plan to attend the extraordinary general meeting, please vote as soon as possible by following the instructions in the accompanying proxy statement/prospectus to make sure that your shares are represented at the extraordinary general meeting. If you hold your shares in “street name” through a bank, broker or other nominee, you will need to follow the instructions provided to you by your bank, broker or other nominee to ensure that your shares are represented and voted at the extraordinary general meeting. The Business Combination will be consummated only if the Condition Precedent Proposals are approved at the extraordinary general meeting. Each of the Condition Precedent Proposals is cross-conditioned on the approval of each other. The Adjournment Proposal is not conditioned on the approval of any other proposal set forth in the accompanying proxy statement/prospectus.

If you sign, date and return your proxy card without indicating how you wish to vote, your proxy will be voted FOR each of the proposals presented at the extraordinary general meeting. If you fail to return your proxy card or fail to instruct your bank, broker or other nominee how to vote, and do not attend the extraordinary general meeting in person, the effect will be, among other things, that your shares will not be counted for purposes of determining whether a quorum is present at the extraordinary general meeting. If you are a shareholder of record and you attend the extraordinary general meeting and wish to vote in person, you may withdraw your proxy and vote in person.

TO EXERCISE YOUR REDEMPTION RIGHTS, YOU MUST DEMAND IN WRITING THAT YOUR PUBLIC SHARES ARE REDEEMED FOR A PRO RATA PORTION OF THE FUNDS HELD IN THE TRUST ACCOUNT AND TENDER YOUR SHARES TO ARCLIGHT’S TRANSFER AGENT AT LEAST TWO BUSINESS DAYS PRIOR TO THE VOTE AT THE EXTRAORDINARY GENERAL MEETING. IN ORDER TO EXERCISE YOUR REDEMPTION RIGHT, YOU NEED TO IDENTIFY YOURSELF AS A BENEFICIAL HOLDER AND PROVIDE YOUR LEGAL NAME, PHONE NUMBER AND ADDRESS IN YOUR WRITTEN DEMAND. YOU MAY TENDER YOUR SHARES BY EITHER DELIVERING YOUR SHARE CERTIFICATE TO THE TRANSFER AGENT OR BY DELIVERING YOUR SHARES ELECTRONICALLY USING THE DEPOSITORY TRUST COMPANY’S DWAC (DEPOSIT WITHDRAWAL AT CUSTODIAN) SYSTEM. IF THE BUSINESS COMBINATION IS NOT COMPLETED, THEN THESE SHARES WILL BE RETURNED TO YOU OR YOUR ACCOUNT. IF YOU HOLD THE SHARES IN STREET NAME, YOU WILL NEED TO INSTRUCT THE ACCOUNT EXECUTIVE AT YOUR BANK OR BROKER TO WITHDRAW THE SHARES FROM YOUR ACCOUNT IN ORDER TO EXERCISE YOUR REDEMPTION RIGHTS.

 

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On behalf of ArcLight’s board of directors, I would like to thank you for your support and look forward to the successful completion of the Business Combination.

 

Sincerely,

   

Daniel R. Revers
Chairman of the Board of Directors

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES REGULATORY AGENCY HAS APPROVED OR DISAPPROVED THE TRANSACTIONS DESCRIBED IN THE ACCOMPANYING PROXY STATEMENT/PROSPECTUS, PASSED UPON THE MERITS OR FAIRNESS OF THE BUSINESS COMBINATION OR RELATED TRANSACTIONS OR PASSED UPON THE ADEQUACY OR ACCURACY OF THE DISCLOSURE IN THE ACCOMPANYING PROXY STATEMENT/PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY CONSTITUTES A CRIMINAL OFFENSE.

The accompanying proxy statement/prospectus is dated              , 2021 and is first being mailed to shareholders on or about              , 2021.

 

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ARCLIGHT CLEAN TRANSITION CORP.

200 Clarendon Street, 55th Floor
Boston, Massachusetts 02116

NOTICE OF EXTRAORDINARY GENERAL MEETING
TO BE HELD ON        
    , 2021

TO THE SHAREHOLDERS OF ARCLIGHT CLEAN TRANSITION CORP.:

NOTICE IS HEREBY GIVEN that an extraordinary general meeting of the shareholders (the “extraordinary general meeting”) of ArcLight Clean Transition Corp., a Cayman Islands exempted company (“ArcLight”), will be held at              ,              Time, on              , 2021, at the offices of Kirkland & Ellis LLP located at              . In the interest of public health, and due to the impact of the coronavirus (“COVID-19”), the extraordinary general meeting may also be attended through a “virtual” or online method. You are cordially invited to attend the extraordinary general meeting, which will be held for the following purposes:

•        Proposal No. 1 — The Business Combination ProposalRESOLVED, as an ordinary resolution, that ArcLight’s entry into the Merger Agreement, dated as of January 11, 2021 (as may be amended, supplemented or otherwise modified from time to time, the “Merger Agreement”), by and among ArcLight, Phoenix Merger Sub, Inc., a Delaware corporation and a wholly-owned direct subsidiary of ArcLight (“Phoenix Merger Sub”), and Proterra Inc, a Delaware corporation (“Proterra”), a copy of which is attached to the proxy statement/prospectus as Annex A, pursuant to which, among other things, following the de-registration of ArcLight as an exempted company in the Cayman Islands and the continuation and domestication of ArcLight as a corporation in the State of Delaware, (a) Phoenix Merger Sub will merge with and into Proterra, with Proterra as the surviving company in the Merger and, after giving effect to the Merger, Proterra will be a wholly-owned subsidiary of ArcLight and (b) at the Effective Time, (i) each share of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for 0.8925 shares of common stock, par value $0.0001 per share, of New Proterra (the “New Proterra Common Stock”), (ii) each warrant and equity award of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for comparable warrants and equity awards that are exercisable for 0.8925 shares of New Proterra Common Stock, and (iii) each outstanding secured convertible promissory notes of Proterra (a “Convertible Note,” collectively the “Convertible Notes”) that is not optionally converted immediately prior to the Effective Time will become convertible into shares of New Proterra Common Stock, in accordance with the terms of the Convertible Note, certain related agreements (including the Subscription Agreements, the Amended and Restated Registration Rights Agreement, the Sponsor Support Agreement, the Sponsor Letter Agreement, Amendment No. 1 to the Sponsor Letter Agreement and the Proterra Stockholder Support Agreements, each in the form attached to the proxy statement/prospectus as Annex E, Annex J, Annex K, Annex L, Annex G and Annex F, respectively), and the transactions contemplated thereby, be approved, ratified and confirmed in all respects.

•        Proposal No. 2 — The Domestication ProposalRESOLVED, as a special resolution, that ArcLight be transferred by way of continuation to Delaware pursuant to Article 47 of ArcLight’s Articles of Association and Section 388 of the General Corporation Law of the State of Delaware and, immediately upon being de-registered in the Cayman Islands, ArcLight be continued and domesticated as a corporation under the laws of the State of Delaware.

•        Governing Documents Proposals — to consider and vote upon the following four (4) separate resolutions to approve that, upon the Domestication, the amended and restated memorandum and articles of association of ArcLight (“Existing Governing Documents”) be amended and restated by the deletion in their entirety and the substitution in their place of the proposed new certificate of incorporation, a copy of which is attached to the proxy statement/prospectus as Annex C (the “Proposed

 

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Certificate of Incorporation”) and the proposed new bylaws, a copy of which is attached to the proxy statement/prospectus as Annex D (the “Proposed Bylaws”) upon the Domestication (such proposals, collectively, the “Governing Documents Proposals”):

•        Proposal No. 3 — Governing Documents Proposal A — RESOLVED, as an ordinary resolution, that the change in the authorized share capital of ArcLight from US$55,500 divided into (i) 500,000,000 Class A ordinary shares, par value $0.0001 per share, 50,000,000 Class B ordinary shares, par value $0.0001 per share, and 5,000,000 preference shares, par value $0.0001 per share, to (ii) 500,000,000 shares of common stock, par value $0.0001 per share, of New Proterra and 10,000,000 shares of preferred stock, par value $0.0001 per share, of New Proterra be approved.

•        Proposal No. 4 — Governing Documents Proposal B — RESOLVED, as an ordinary resolution, that the authorization to the New Proterra Board to issue any or all shares of New Proterra Preferred Stock in one or more classes or series, with such terms and conditions as may be expressly determined by the New Proterra Board and as may be permitted by the Delaware General Corporation Law be approved.

•        Proposal No. 5 — Governing Documents Proposal C — RESOLVED, as an ordinary resolution, that the removal of the ability of New Proterra stockholders to take action by written consent in lieu of a meeting be approved.

•        Proposal No. 6 — Governing Documents Proposal D — RESOLVED, as a special resolution, that the amendment and restatement of the Existing Governing Documents be approved and that all other changes necessary or, as mutually agreed in good faith by ArcLight and Proterra, desirable in connection with the replacement of Existing Governing Documents with the Proposed Certificate of Incorporation and Proposed Bylaws as part of the Domestication (copies of which are attached to the proxy statement/prospectus as Annex C and Annex D, respectively), including (i) making New Proterra’s corporate existence perpetual, (ii) adopting Delaware as the exclusive forum for certain stockholder litigation, provided, that the exclusive forum provision in our restated certificate of incorporation does not apply to claims arising out of the Securities Act of 1933, as amended, and the Securities Exchange Act of 1934, as amended, for which the federal district courts of the United States are the exclusive forum, and (iii) removing certain provisions related to our status as a blank check company that will no longer be applicable upon consummation of the Business Combination be approved.

•        Proposal No. 7 — The Nasdaq ProposalRESOLVED, as an ordinary resolution, that for the purposes of complying with the applicable provisions of Nasdaq Listing Rule 5635, the issuance of shares of New Proterra Common Stock be approved.

•        Proposal No. 8 — The Equity Incentive Plan ProposalRESOLVED, as an ordinary resolution, that the Proterra Inc 2021 Equity Incentive Plan, a copy of which is attached to the proxy statement/prospectus as Annex H, be adopted and approved.

•        Proposal No. 9 — The Employee Stock Purchase Plan ProposalRESOLVED, as an ordinary resolution, that the Proterra Inc 2021 Employee Stock Purchase Plan, a copy of which is attached to the proxy statement/prospectus as Annex I, be adopted and approved.

•        Proposal No. 10 — The Adjournment ProposalRESOLVED, as an ordinary resolution, that the adjournment of the extraordinary general meeting to a later date or dates (A) to the extent necessary to ensure that any required supplement or amendment to the proxy statement/prospectus is provided to ArcLight shareholders or, if as of the time for which the extraordinary general meeting is scheduled, there are insufficient ArcLight ordinary shares represented (either in person or by proxy) to constitute a quorum necessary to conduct business at the extraordinary general meeting, (B) in order to solicit additional proxies from ArcLight shareholders in favor of one or more of the proposals at the extraordinary general meeting or (C) if ArcLight shareholders redeem an amount of the public shares such that one of the conditions to consummate the Business

 

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Combination that the aggregate cash proceeds to be received by ArcLight from the trust account in connection with the Business Combination, together with the aggregate gross proceeds from the PIPE Financing, equal no less than $300,000,000 as a condition to ArcLight’s obligation to close or $350,000,000 as a condition to Proterra’s obligation to close (in each case, after deducting any amounts paid to ArcLight’s stockholders that exercise their redemption rights in connection with the Business Combination and net of unpaid transaction expenses incurred or subject to reimbursement by ArcLight) would not be satisfied at Closing, be approved.

Each of the Business Combination Proposal, the Domestication Proposal, the Governing Documents Proposals, the Nasdaq Proposal, the Equity Incentive Plan Proposal and the Employee Stock Purchase Plan Proposal is conditioned on the approval and adoption of each of the other Condition Precedent Proposals. The Adjournment Proposal is not conditioned on any other proposal.

These items of business are described in this proxy statement/prospectus, which we encourage you to read carefully and in its entirety before voting.

Only holders of record of ordinary shares at the close of business on            , 2021 are entitled to notice of and to vote and have their votes counted at the extraordinary general meeting and any adjournment of the extraordinary general meeting.

This proxy statement/prospectus and accompanying proxy card is being provided to ArcLight’s shareholders in connection with the solicitation of proxies to be voted at the extraordinary general meeting and at any adjournment of the extraordinary general meeting. Whether or not you plan to attend the extraordinary general meeting, all of ArcLight’s shareholders are urged to read this proxy statement/prospectus, including the Annexes and the documents referred to herein carefully and in their entirety. You should also carefully consider the risk factors described in “Risk Factorsbeginning on page 28 of this proxy statement/prospectus.

After careful consideration, the board of directors of ArcLight has unanimously approved the Merger Agreement and the transactions contemplated thereby, including the Merger, and unanimously recommends that shareholders vote “FOR” the adoption of the Merger Agreement and approval of the transactions contemplated thereby, including the Merger, and “FOR” all other proposals presented to ArcLight’s shareholders in this proxy statement/prospectus. When you consider the recommendation of these proposals by the board of directors of ArcLight, you should keep in mind that ArcLight’s directors and officers have interests in the Business Combination that may conflict with your interests as a shareholder. See the section entitled “Business Combination Proposal — Interests of ArcLight’s Directors and Executive Officers in the Business Combination” in this proxy statement/prospectus for a further discussion of these considerations.

Pursuant to the Existing Governing Documents, a public shareholder may request that ArcLight redeem all or a portion of its public shares for cash if the Business Combination is consummated. As a holder of public shares, you will be entitled to receive cash for any public shares to be redeemed only if you:

(i)     (a) hold public shares or (b) if you hold public shares through units, you elect to separate your units into the underlying public shares and warrants prior to exercising your redemption rights with respect to the public shares;

(ii)    submit a written request to Continental, ArcLight’s transfer agent, in which you (i) request that ArcLight redeem all or a portion of your public shares for cash, and (ii) identify yourself as the beneficial holder of the public shares and provide your legal name, phone number and address; and

(iii)   deliver your public shares to Continental, ArcLight’s transfer agent, physically or electronically through The Depository Trust Company.

Holders must complete the procedures for electing to redeem their public shares in the manner described above prior to            ,            Time, on            , 2021 (two business days before the extraordinary general meeting) in order for their shares to be redeemed.

Holders of units must elect to separate the units into the underlying public shares and warrants prior to exercising redemption rights with respect to the public shares. Public holders that hold their units in an account at a brokerage firm or bank, must notify their broker or bank that they elect to separate the units into the underlying

 

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public shares and warrants, or if a holder holds units registered in its own name, the holder must contact Continental, ArcLight’s transfer agent, directly and instruct them to do so. The redemption rights include the requirement that a holder must identify itself in writing as a beneficial holder and provide its legal name, phone number and address to Continental in order to validly redeem its shares. Public shareholders may elect to redeem public shares regardless of if or how they vote in respect of the Business Combination Proposal. If the Business Combination is not consummated, the public shares will be returned to the respective holder, broker or bank. If the Business Combination is consummated, and if a public shareholder properly exercises its right to redeem all or a portion of the public shares that it holds and timely delivers its shares to Continental, ArcLight’s transfer agent, New Proterra will redeem such public shares for a per-share price, payable in cash, equal to the pro rata portion of the trust account established at the consummation of ArcLight’s initial public offering (the “trust account”), calculated as of two business days prior to the consummation of the Business Combination. For illustrative purposes, this would have amounted to approximately $10.56 per issued and outstanding public share, based on 26,290,616 shares subject to possible redemption as of December 31, 2020. If a public shareholder exercises its redemption rights in full, then it will be electing to exchange its public shares for cash and will no longer own public shares. The redemption will take place following the Domestication and, accordingly, it is shares of New Proterra Common Stock that will be redeemed immediately after consummation of the Business Combination. See “Extraordinary General Meeting of ArcLight — Redemption Rights” in this proxy statement/prospectus for a detailed description of the procedures to be followed if you wish to redeem your public shares for cash.

Notwithstanding the foregoing, a public shareholder, together with any affiliate of such public shareholder or any other person with whom such public shareholder is acting in concert or as a “group” (as defined in Section 13(d)(3) of the Securities Exchange Act of 1934, as amended (“Exchange Act”)), will be restricted from redeeming its public shares with respect to more than an aggregate of 15% of the public shares. Accordingly, if a public shareholder, alone or acting in concert or as a group, seeks to redeem more than 15% of the public shares, then any such shares in excess of that 15% limit would not be redeemed for cash.

Our Initial Shareholders have, pursuant to the Sponsor Support Agreement, agreed to, among other things, vote all of their ordinary shares in favor of the proposals being presented at the extraordinary general meeting and waive their anti-dilution rights with respect to their Class B ordinary shares in connection with the consummation of the Business Combination. Such shares will be excluded from the pro rata calculation used to determine the per-share redemption price. As of the date of this proxy statement/prospectus, the Initial Shareholders own 20.0% of the issued and outstanding ordinary shares. See “Business Combination Proposal — Related Agreements — Sponsor Support Agreement” in the accompanying proxy statement/prospectus for more information related to the Sponsor Letter Agreement.

The Merger Agreement is subject to the satisfaction or waiver of certain other closing conditions as described in the accompanying proxy statement/prospectus. There can be no assurance that the parties to the Merger Agreement would waive any such provision of the Merger Agreement. In addition, in no event will ArcLight redeem public shares in an amount that would cause New Proterra’s net tangible assets (as determined in accordance with Rule 3a51-1(g)(1) of the Exchange Act) to be less than $5,000,001 after giving effect to the transactions contemplated by the Merger Agreement and the PIPE Financing.

The approval of the Domestication Proposal requires a special resolution under Cayman Islands law, being the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter. The approval of each of the Business Combination Proposal, the Governing Documents Proposals (other than Proposal D), the Equity Incentive Plan Proposal, the Employee Stock Purchase Plan Proposal, the Nasdaq Proposal and the Adjournment Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

Your vote is very important.    Whether or not you plan to attend the extraordinary general meeting, please vote as soon as possible by following the instructions in this proxy statement/prospectus to make sure that your shares are represented at the extraordinary general meeting. If you hold your shares in “street name” through a bank, broker or other nominee, you will need to follow the instructions provided to you by your bank, broker or other nominee to ensure that your shares are represented and voted at the extraordinary general meeting. The Business Combination will be consummated only if the Condition Precedent

 

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Proposals are approved at the extraordinary general meeting. Each of the Condition Precedent Proposals is cross-conditioned on the approval of each other. The Adjournment Proposal is not conditioned on the approval of any other proposal set forth in this proxy statement/prospectus.

If you sign, date and return your proxy card without indicating how you wish to vote, your proxy will be voted FOR each of the proposals presented at the extraordinary general meeting. If you fail to return your proxy card or fail to instruct your bank, broker or other nominee how to vote, and do not attend the extraordinary general meeting in person, the effect will be, among other things, that your shares will not be counted for purposes of determining whether a quorum is present at the extraordinary general meeting. If you are a shareholder of record and you attend the extraordinary general meeting and wish to vote in person, you may withdraw your proxy and vote in person.

Your attention is directed to the remainder of the proxy statement/prospectus following this notice (including the Annexes and other documents referred to herein) for a more complete description of the proposed Business Combination and related transactions and each of the proposals. You are encouraged to read this proxy statement/prospectus carefully and in its entirety, including the Annexes and other documents referred to herein. If you have any questions or need assistance voting your ordinary shares, please contact Morrow Sodali LLC, our proxy solicitor, by calling (800) 662-5200, or banks and brokers can call collect at (203) 658-9400, or by emailing ACTC.info@investor.morrowsodali.com.

Thank you for your participation. We look forward to your continued support.

By Order of the Board of Directors of ArcLight Clean Transition Corp.,

Daniel R. Revers

Chairman of the Board of Directors

TO EXERCISE YOUR REDEMPTION RIGHTS, YOU MUST DEMAND IN WRITING THAT YOUR PUBLIC SHARES ARE REDEEMED FOR A PRO RATA PORTION OF THE FUNDS HELD IN THE TRUST ACCOUNT AND TENDER YOUR SHARES TO ARCLIGHT’S TRANSFER AGENT AT LEAST TWO BUSINESS DAYS PRIOR TO THE VOTE AT THE EXTRAORDINARY GENERAL MEETING. IN ORDER TO EXERCISE YOUR REDEMPTION RIGHT, YOU NEED TO IDENTIFY YOURSELF AS A BENEFICIAL HOLDER AND PROVIDE YOUR LEGAL NAME, PHONE NUMBER AND ADDRESS IN YOUR WRITTEN DEMAND. YOU MAY TENDER YOUR SHARES BY EITHER DELIVERING YOUR SHARE CERTIFICATE TO THE TRANSFER AGENT OR BY DELIVERING YOUR SHARES ELECTRONICALLY USING THE DEPOSITORY TRUST COMPANY’S DWAC (DEPOSIT WITHDRAWAL AT CUSTODIAN) SYSTEM. IF THE BUSINESS COMBINATION IS NOT COMPLETED, THEN THESE SHARES WILL BE RETURNED TO YOU OR YOUR ACCOUNT. IF YOU HOLD THE SHARES IN STREET NAME, YOU WILL NEED TO INSTRUCT THE ACCOUNT EXECUTIVE AT YOUR BANK OR BROKER TO WITHDRAW THE SHARES FROM YOUR ACCOUNT IN ORDER TO EXERCISE YOUR REDEMPTION RIGHTS.

 

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TABLE OF CONTENTS

 

Page

ADDITIONAL INFORMATION

 

iii

TRADEMARKS

 

iii

SELECTED DEFINITIONS

 

iv

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

 

vii

QUESTIONS AND ANSWERS FOR SHAREHOLDERS OF ARCLIGHT

 

x

SUMMARY OF THE PROXY STATEMENT/PROSPECTUS

 

1

SELECTED HISTORICAL FINANCIAL INFORMATION OF ARCLIGHT

 

21

SELECTED HISTORICAL FINANCIAL INFORMATION OF PROTERRA

 

22

SUMMARY UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL
INFORMATION

 

24

COMPARATIVE PER SHARE DATA

 

26

RISK FACTORS

 

28

EXTRAORDINARY GENERAL MEETING OF ARCLIGHT

 

88

BUSINESS COMBINATION PROPOSAL

 

94

DOMESTICATION PROPOSAL

 

121

GOVERNING DOCUMENTS PROPOSALS

 

124

GOVERNING DOCUMENTS PROPOSAL A — APPROVAL OF AUTHORIZATION OF CHANGE TO AUTHORIZED SHARE CAPITAL, AS SET FORTH IN THE PROPOSED GOVERNING DOCUMENTS

 

126

GOVERNING DOCUMENTS PROPOSAL B —APPROVAL OF PROPOSAL REGARDING ISSUANCE OF PREFERRED STOCK OF NEW PROTERRA AT THE BOARD OF DIRECTORS’ SOLE DISCRETION, AS SET FORTH IN THE PROPOSED GOVERNING DOCUMENTS

 

128

GOVERNING DOCUMENTS PROPOSAL C — APPROVAL OF PROPOSAL REGARDING THE ABILITY OF STOCKHOLDERS TO ACT BY WRITTEN CONSENT, AS SET FORTH IN THE PROPOSED GOVERNING DOCUMENTS

 

130

GOVERNING DOCUMENTS PROPOSAL D — APPROVAL OF OTHER CHANGES IN CONNECTION WITH ADOPTION OF THE PROPOSED GOVERNING DOCUMENTS

 

132

NASDAQ PROPOSAL

 

135

2021 EQUITY INCENTIVE PLAN PROPOSAL

 

137

EMPLOYEE STOCK PURCHASE PLAN PROPOSAL

 

143

ADJOURNMENT PROPOSAL

 

147

U.S. FEDERAL INCOME TAX CONSIDERATIONS

 

149

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

 

162

NOTES TO UNAUDITED PRO FORMA COMBINED FINANCIAL INFORMATION

 

169

INFORMATION ABOUT ARCLIGHT

 

174

ARCLIGHT’S MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

 

188

INFORMATION ABOUT PROTERRA

 

192

PROTERRA’S MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

 

214

MANAGEMENT OF NEW PROTERRA FOLLOWING THE BUSINESS COMBINATION

 

241

BENEFICIAL OWNERSHIP OF SECURITIES

 

253

CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS

 

258

COMPARISON OF CORPORATE GOVERNANCE AND SHAREHOLDER RIGHTS

 

263

DESCRIPTION OF NEW PROTERRA SECURITIES

 

266

SECURITIES ACT RESTRICTIONS ON RESALE OF NEW PROTERRA COMMON STOCK

 

278

STOCKHOLDER PROPOSALS AND NOMINATIONS

 

279

SHAREHOLDER COMMUNICATIONS

 

279

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ADDITIONAL INFORMATION

You may request copies of this proxy statement/prospectus and any other publicly available information concerning ArcLight, without charge, by written request to ArcLight Clean Transition Corp., 200 Clarendon Street, 55th Floor, Boston, Massachusetts, 02116, or by telephone request at (617) 531-6300; or Morrow Sodali LLC, our proxy solicitor, by calling (800) 662-5200, or banks and brokers can call collect at (203) 658-9400, or by emailing ACTC.info@investor.morrowsodali.com or from the SEC through the SEC website at http://www.sec.gov.

In order for ArcLight’s shareholders to receive timely delivery of the documents in advance of the extraordinary general meeting of ArcLight to be held on           , 2021, you must request the information no later than five business days prior to the date of the extraordinary general meeting, by            , 2021.

TRADEMARKS

This document contains references to trademarks, trade names and service marks belonging to other entities. Solely for convenience, trademarks, trade names and service marks referred to in this proxy statement/prospectus may appear without the ® or TM symbols, but such references are not intended to indicate, in any way, that the applicable licensor will not assert, to the fullest extent under applicable law, its rights to these trademarks and trade names. We do not intend our use or display of other companies’ trade names, trademarks or service marks to imply a relationship with, or endorsement or sponsorship of us by, any other companies.

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SELECTED DEFINITIONS

Unless otherwise stated in this proxy statement/prospectus or the context otherwise requires, the following terms shall have the following meanings:

•        “Aggregate Transaction Proceeds” means the aggregate funds in the trust account immediately prior to the Closing, together with the aggregate gross proceeds from the PIPE Financing, after deducting any amounts paid to ArcLight shareholders that exercise their redemption rights in connection with the Business Combination;

•        “ArcLight,” “we,” “us” or “our” means ArcLight Clean Transition Corp., a Cayman Islands exempted company, prior to the consummation of the Business Combination;

•        “ArcLight Board” means ArcLight’s board of directors;

•        “ArcLight warrant agreement” means the warrant agreement, dated September 25, 2020, between ArcLight and Continental Stock Transfer & Trust Company, as warrant agent, which sets forth the expiration and exercise price of and procedure for exercising the warrants;

•        “Articles of Association” means the amended and restated articles of association of ArcLight;

•        “Business Combination” means the Domestication, the Merger and other transactions contemplated by the Merger Agreement, collectively, including the PIPE Financing;

•        “Cayman Islands Companies Law” means the Companies Act (As Revised) of the Cayman Islands as the same may be amended from time to time;

•        “Class A ordinary shares” means the Class A ordinary shares, par value $0.0001 per share, of ArcLight, which will automatically convert into a number of shares of New Proterra Common Stock, on a one-for-one basis, in connection with the Domestication;

•        “Class B ordinary shares” or “founder shares” means the 6,937,500 Class B ordinary shares, par value $0.0001 per share, of ArcLight outstanding as of the date of this proxy statement/prospectus that were initially issued to our Sponsor (a portion of which were subsequently transferred to the other Initial Shareholders) in a private placement prior to our initial public offering, and, in connection with the Domestication, will automatically convert, on a one-for-one basis, into shares of New Proterra Common Stock (6,797,500 of which are held by the Sponsor, and 10% of which are subject to certain vesting and forfeiture terms as described in this proxy statement/prospectus);

•        “Closing” means the closing of the Business Combination;

•        “Closing Date” means that date that is in no event later than the third (3rd) business day, following the satisfaction (or, to the extent permitted by applicable law, waiver) of the conditions described under the section entitled “Business Combination Proposal — The Merger Agreement — Conditions to Closing of the Business Combination,” (other than those conditions that by their nature are to be satisfied at the Closing, but subject to satisfaction or waiver of such conditions) or at such other date as ArcLight and Proterra may agree in writing;

•        “Condition Precedent Proposals” means the Business Combination Proposal, the Domestication Proposal, the Governing Documents Proposals, the Nasdaq Proposal and the Equity Incentive Plan Proposal and the Employee Stock Purchase Plan Proposal, collectively;

•        “Continental” means Continental Stock Transfer & Trust Company;

•        “Convertible Notes” means the Proterra secured convertible promissory notes in aggregate principal amount of $200.0 million issued in August 2020.

•        “Domestication” means the transfer by way of continuation and deregistration of ArcLight from the Cayman Islands and the continuation and domestication of ArcLight as a corporation incorporated in the State of Delaware;

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•        “Effective Time” means the time at which the Merger becomes effective;

•        “Equity Incentive Plan” means the Proterra Inc 2021 Equity Incentive Plan to be considered for adoption and approval by the shareholders pursuant to the Equity Incentive Plan Proposal;

•        “ESPP” means the Proterra Inc 2021 Employee Stock Purchase Plan to be considered for adoption and approval by the shareholders pursuant to the Employee Stock Purchase Plan Proposal;

•        “extraordinary general meeting” means the extraordinary general meeting of ArcLight at             ,     Time, on           , 2021, at the offices of Kirkland & Ellis LLP located at               , and via a virtual meeting, unless the extraordinary general meeting is adjourned, or at such other time, on such other date and at such other place to which the meeting may be adjourned;

•        “Existing Governing Documents” means the Memorandum of Association and the Articles of Association;

•        “initial public offering” means ArcLight’s initial public offering that was consummated on September 25, 2020;

•        “GAAP” means the United States generally accepted accounting principles, consistently applied;

•        “Initial Shareholders” means the Sponsor and ArcLight’s four independent directors who hold Class B ordinary shares;

•        “Memorandum of Association” means the amended and restated memorandum of association of ArcLight;

•        “Merger” means the merger of Phoenix Merger Sub with and into Proterra pursuant to the Merger Agreement, with Proterra as the surviving company in the Merger and, after giving effect to such Merger, Proterra becoming a wholly-owned subsidiary of ArcLight;

•        “Merger Agreement” means that certain Merger Agreement, dated as of January 11, 2021 (as may be amended, supplemented or otherwise modified from time to time), by and among ArcLight, Phoenix Merger Sub and Proterra;

•        “Nasdaq” means the Nasdaq Capital Market;

•        “New Proterra” means ArcLight upon and after the Domestication;

•        “New Proterra Board” means the board of directors of New Proterra;

•        “New Proterra Common Stock” means the common stock, par value $0.0001 per share, of New Proterra;

•        “ordinary shares” refer to our Class A ordinary shares and our Class B ordinary shares;

•        “Phoenix Merger Sub” refers to Phoenix Merger Sub, Inc., a Delaware corporation and a wholly-owned direct subsidiary of ArcLight;

•        “PIPE Financing” means the transactions contemplated by the Subscription Agreements, pursuant to which the PIPE Investors have collectively committed to subscribe for an aggregate of 41,500,000 shares of New Proterra Common Stock for an aggregate purchase price of $415,000,000 to be consummated in connection with the Closing;

•        “PIPE Investors” means the investors who agreed to participate in the PIPE Financing and entered into the Subscription Agreements;

•        “private placement shares” means Class A ordinary shares of ArcLight underlying the private placement warrants;

•        “private placement warrants” means the 7,550,000 private placement warrants outstanding as of the date of this proxy statement/ prospectus that were issued to our Sponsor as part of the initial public offering, which are substantially identical to the public warrants sold as part of the units in the initial public offering, subject to certain limited exceptions;

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•        “pro forma” means giving pro forma effect to the Business Combination, including the Merger and the PIPE Financing;

•        “Proposed Bylaws” means the proposed bylaws of New Proterra to be effective upon the Domestication attached to this proxy statement/prospectus as Annex D;

•        “Proposed Certificate of Incorporation” means the proposed certificate of incorporation of New Proterra to be effective upon the Domestication attached to this proxy statement/prospectus as Annex C;

•        “Proposed Governing Documents” means the Proposed Certificate of Incorporation and the Proposed Bylaws;

•        “Proterra” means Proterra Inc, a Delaware corporation, prior to the consummation of the Business Combination;

•        “Proterra Acquisition Proposal” means (a) any transaction or series of related transactions under which any person(s), directly or indirectly, (i) acquires or otherwise purchases Proterra or any of its controlled affiliates or (ii) all or a material portion of assets or businesses of Proterra or any of its controlled affiliates (in the case of each of clause (i) and (ii), whether by merger, consolidation, recapitalization, purchase or issuance of equity securities, tender offer or otherwise); or (b) any equity or similar investment in Proterra or any of its controlled affiliates (subject to exceptions to the PIPE Financing or the issuance of the applicable class of shares of capital stock of Proterra upon the exercise or conversion of any outstanding Proterra equity awards);

•        “Proterra Common Stock” means common stock of Proterra, par value $0.0001 per share;

•        “Proterra Holders” means holders of (i) Proterra Common Stock, (ii) preferred stock of Proterra, (iii) Convertible Notes and (iv) any other securities of Proterra that provide the holder thereof the right to acquire shares of New Proterra Common Stock in connection with the Business Combination, including warrants and equity awards of Proterra, held immediately prior to Closing;

•        “public shareholders” means holders of public shares, whether acquired in ArcLight’s initial public offering or acquired in the secondary market;

•        “public shares” means the currently outstanding 27,750,000 Class A ordinary shares of ArcLight, whether acquired in ArcLight’s initial public offering or acquired in the secondary market;

•        “public warrants” means the currently outstanding 13,875,000 redeemable warrants to purchase Class A ordinary shares of ArcLight that were issued by ArcLight in its initial public offering;

•        “redemption” means each redemption of public shares for cash pursuant to the Existing Governing Documents;

•        “SEC” means the Securities and Exchange Commission;

•        “Securities Act” means the Securities Act of 1933, as amended;

•        “Sponsor” means ArcLight CTC Holdings, L.P., a Delaware limited partnership;

•        “Subscription Agreements” means the subscription agreements, entered into by ArcLight and each of the PIPE Investors in connection with the PIPE Financing;

•        “transfer agent” means Continental, ArcLight’s transfer agent;

•        “trust account” means the trust account established at the consummation of ArcLight’s initial public offering that holds the proceeds of the initial public offering and is maintained by Continental, acting as trustee;

•        “units” means the units of ArcLight, each unit representing one Class A ordinary share and one-half of one warrant, with such whole warrant representing the right to acquire one Class A ordinary share, that were offered and sold by ArcLight in its initial public offering and in its concurrent private placement; and

•        “warrants” means the public warrants and the private placement warrants.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements in this proxy statement/prospectus may constitute “forward-looking statements” for purposes of the federal securities laws. Our forward-looking statements include, but are not limited to, statements regarding our or our management team’s expectations, hopes, beliefs, intentions or strategies regarding the future, including those relating to the Business Combination. The information included in this proxy statement/prospectus in relation to Proterra has been provided by Proterra and its respective management, and forward-looking statements include statements relating to our and its respective management team’s expectations, hopes, beliefs, intentions or strategies regarding the future, including those relating to the Business Combination. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. The words “anticipate,” “believe,” “contemplate,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “might,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “will,” “would” and similar expressions may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. Forward-looking statements in this proxy statement/prospectus may include, for example, statements about:

•        our ability to complete the Business Combination with Proterra or, if we do not consummate such Business Combination, any other initial business combination;

•        satisfaction or waiver of the conditions to the Business Combination including, among others: (i) the approval by our shareholders of the Condition Precedent Proposals being obtained; (ii) the applicable waiting period under the Hart-Scott-Rodino Act of 1976 (the “HSR Act”) relating to the Merger Agreement having expired or been terminated; (iii) the Aggregate Transaction Proceeds Condition; and (iv) the approval by Nasdaq of our initial listing application in connection with the Business Combination;

•        the occurrence of any event, change or other circumstances, including the outcome of any legal proceedings that may be instituted against ArcLight and Proterra following the announcement of the Merger Agreement and the transactions contemplated therein, that could give rise to the termination of the Merger Agreement;

•        New Proterra’s financial and business performance following the Business Combination, including financial projections and business metrics;

•        the ability to obtain and/or maintain the listing of the New Proterra Common Stock and the warrants on Nasdaq, and the potential liquidity and trading of such securities;

•        the amount of redemptions made by public shareholders;

•        the risk that the proposed Business Combination disrupts current plans and operations of Proterra as a result of the announcement and consummation of the proposed Business Combination;

•        the ability to recognize the anticipated benefits of the proposed Business Combination, which may be affected by, among other things, competition, the ability of the combined company to grow and manage growth profitably and retain its key employees;

•        costs related to the proposed Business Combination;

•        changes in applicable laws or regulations;

•        our success in retaining or recruiting, or changes required in, our officers, key employees or directors following the completion of the Business Combination, and New Proterra’s ability to attract and retain key personnel;

•        our officers and directors allocating their time to other businesses and potentially having conflicts of interest with our business or in approving the Business Combination;

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•        the anticipated success of New Proterra’s most recent business expansion with Proterra Powered and Proterra Energy, and New Proterra’s ability to attract the customers and business partners it expects;

•        forecasts regarding long-term end-customer adoption rates and demand for New Proterra’s products in markets that are new and rapidly evolving;

•        New Proterra’s ability to compete successfully against current and future competitors in light of intense and increasing competition in the transit bus and commercial vehicle electrification market;

•        macroeconomic conditions resulting from the global COVID-19 pandemic;

•        the availability of government economic incentives and government funding for public transit upon which New Proterra’s transit business is significantly dependent;

•        willingness of corporate and other public transportation providers to adopt and fund the purchase of electric vehicles for mass transit;

•        availability of a limited number of suppliers for New Proterra’s products and services;

•        material losses and costs from product warranty claims, recalls, or remediation of electric transit buses for real or perceived deficiencies or from customer satisfaction campaigns;

•        increases in costs, disruption of supply, or shortage of materials, particularly lithium-ion cells;

•        New Proterra’s dependence on a small number of customers that fluctuate from year to year, and failure to add new customers or expand sales to New Proterra’s existing customers;

•        rapid evolution of New Proterra’s industry and technology, and related unforeseen changes, including developments in alternative technologies and powertrains or improvements in the internal combustion engine that could adversely affect the demand for New Proterra’s electric transit buses;

•        development, maintenance and growth of strategic relationships in the Proterra Powered or Proterra Energy business, identification of new strategic relationship opportunities, or formation strategic relationships;

•        competition for the business of both small and large transit agencies, which place different demands on New Proterra’s business, including the need to build an organization that can serve both types of transit customers;

•        substantial regulations, which are evolving, and unfavorable changes or failure by New Proterra to comply with these regulations;

•        accident or safety incidents involving Proterra’s buses, battery systems, electric drivetrains, high-voltage systems or charging solutions;

•        product liability claims, which could harm New Proterra’s financial condition and liquidity if New Proterra is not able to successfully defend or insure against such claims;

•        changes to U.S. trade policies, including new tariffs or the renegotiation or termination of existing trade agreements or treaties;

•        various environmental and safety laws and regulations that could impose substantial costs upon Proterra and negatively impact New Proterra’s ability to operate New Proterra’s manufacturing facilities; outages and disruptions of New Proterra’s services if it fails to maintain adequate security and supporting infrastructure as it scales New Proterra’s information technology systems;

•        availability of additional capital to support business growth;

•        failure to protect New Proterra’s intellectual property;

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•        intellectual property rights claims by third parties, which could be costly to defend, related significant damages and resulting limits on New Proterra’s ability to use certain technologies. developments and projections relating to New Proterra’s competitors and industry;

•        the anticipated growth rates and market opportunities of New Proterra;

•        the period over which New Proterra anticipates its existing cash and cash equivalents will be sufficient to fund its operating expenses and capital expenditure requirements;

•        the potential for New Proterra’s business development efforts to maximize the potential value of its portfolio;

•        New Proterra’s ability to attract and retain key personnel;

•        New Proterra’s estimates regarding expenses, future revenue, capital requirements and needs for additional financing;

•        New Proterra’s financial performance;

•        the inability to develop and maintain effective internal controls;

•        the diversion of management’s attention and consumption of resources as a result of potential acquisitions of other companies;

•        failure to maintain adequate operational and financial resources or raise additional capital or generate sufficient cash flows;

•        cyber-attacks and security vulnerabilities;

•        the effect of the novel coronavirus (“COVID-19”) pandemic on the foregoing, including our ability to consummate the Business Combination due to the uncertainty resulting from the recent COVID-19 pandemic; and

•        other factors detailed under the section entitled “Risk Factors.”

The forward-looking statements contained in this proxy statement/prospectus are based on current expectations and beliefs concerning future developments and their potential effects on us and/or Proterra. There can be no assurance that future developments affecting us and/or Proterra will be those that we and/or Proterra have anticipated. These forward-looking statements involve a number of risks, uncertainties (some of which are beyond our control or the control of Proterra) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to, those factors described under the heading “Risk Factors.” Should one or more of these risks or uncertainties materialize, or should any of our assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. Some of these risks and uncertainties may in the future be amplified by the COVID-19 outbreak and there may be additional risks that we consider immaterial or which are unknown. It is not possible to predict or identify all such risks. Neither we nor Proterra undertake any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required under applicable securities laws.

Before any shareholder grants its proxy or instructs how its vote should be cast or vote on the proposals to be put to the extraordinary general meeting, such stockholder should be aware that the occurrence of the events described in the “Risk Factors” section and elsewhere in this proxy statement/prospectus may adversely affect us.

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QUESTIONS AND ANSWERS FOR SHAREHOLDERS OF ARCLIGHT

The questions and answers below highlight only selected information from this document and only briefly address some commonly asked questions about the proposals to be presented at the extraordinary general meeting, including with respect to the proposed Business Combination. The following questions and answers do not include all the information that is important to ArcLight’s shareholders. We urge shareholders to read this proxy statement/prospectus, including the Annexes and the other documents referred to herein, carefully and in their entirety to fully understand the proposed Business Combination and the voting procedures for the extraordinary general meeting, which will be held at               , on         , 2021, at the offices of Kirkland & Ellis LLP located at         and via a virtual meeting, unless the extraordinary general meeting is adjourned.

Q:     Why am I receiving this proxy statement/prospectus?

A:     ArcLight shareholders are being asked to consider and vote upon, among other proposals, a proposal to approve and adopt the Merger Agreement and approve the transactions contemplated thereby, including the Business Combination. In accordance with the terms and subject to the conditions of the Merger Agreement, among other things, in connection with the Domestication, on the Closing Date prior to the Effective Time, (i) each share of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for 0.8925 shares of New Proterra Common Stock, (ii) each warrant and equity award of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for comparable warrants or equity awards that are exercisable for 0.8925 shares of New Proterra Common Stock, as applicable, and (iii) each Convertible Note that is not optionally converted immediately prior to the Effective Time will become convertible into shares of New Proterra Common Stock, in accordance with the terms of the Convertible Note. For further details, see “Business Combination Proposal — Consideration to Proterra Holders in the Business Combination.”

A copy of the Merger Agreement is attached to this proxy statement/prospectus as Annex A and you are encouraged to read the Merger Agreement in its entirety.

The approval of each of the Business Combination Proposal, the Governing Documents Proposals (other than Proposal D), the Equity Incentive Plan Proposal, the Employee Stock Purchase Plan Proposal, the Nasdaq Proposal and the Adjournment Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter, and the Domestication Proposal requires a special resolution under Cayman Islands law, being the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

In connection with the Domestication, on the Closing Date prior to the Effective Time, (i) each issued and outstanding Class A ordinary share will convert automatically by operation of law, on a one-for-one basis, into shares of New Proterra Common Stock; (ii) each issued and outstanding Class B ordinary share of ArcLight will convert automatically by operation of law, on a one-for-one basis, into shares of New Proterra Common Stock, (iii) each issued and outstanding warrant to purchase Class A ordinary shares of ArcLight will automatically represent the right to purchase one share of New Proterra Common Stock at an exercise price of $11.50 per share of New Proterra Common Stock on the terms and conditions set forth in the warrant agreement; and (iv) each issued and outstanding unit of ArcLight that has not been previously separated into the underlying Class A ordinary share and underlying warrant upon the request of the holder thereof, will be cancelled and will entitle the holder thereof to one share of New Proterra Common Stock and one-half of one warrant, with such whole warrant representing the right to acquire one share of New Proterra Common Stock. In connection with clause (i), (ii) and (iii), each issued and outstanding unit of ArcLight that has not been previously separated into the underlying Class A ordinary shares of ArcLight and underlying ArcLight warrants prior to the Domestication will be cancelled and will entitle the holder thereof to one share of New Proterra Common Stock and one-half of one warrant, a whole warrant representing the right to purchase one share of New Proterra Common Stock at an exercise price of $11.50 per share on the terms and subject to the conditions set forth in the ArcLight warrant agreement. See “Domestication Proposal.”

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The provisions of the Proposed Governing Documents will differ in certain material respects from the Existing Governing Documents. Please see “What amendments will be made to the Existing Governing Documents of ArcLight?” below.

THE VOTE OF SHAREHOLDERS IS IMPORTANT. SHAREHOLDERS ARE ENCOURAGED TO VOTE AS SOON AS POSSIBLE AFTER CAREFULLY REVIEWING THIS PROXY STATEMENT/PROSPECTUS.

Q:     What proposals are shareholders of ArcLight being asked to vote upon?

A:     At the extraordinary general meeting, ArcLight is asking holders of its ordinary shares to consider and vote upon ten (10) separate proposals:

•        a proposal to approve by ordinary resolution and adopt the Merger Agreement, including the Merger, and the transactions contemplated thereby;

•        a proposal to approve by special resolution the Domestication;

•        the following four (4) separate proposals to approve by ordinary resolution (other than Proposal D) the following material differences between the Existing Governing Documents and the Proposed Governing Documents:

•        to authorize the change in the authorized share capital of ArcLight from US$55,500 divided into (i) 500,000,000 Class A ordinary shares, par value $0.0001 per share, 50,000,000 Class B ordinary shares, par value $0.0001 per share, and 5,000,000 preference shares, par value $0.0001 per share, to (ii) 500,000,000 shares of New Proterra Common Stock and 10,000,000 shares of New Proterra Preferred Stock;

•        to authorize the New Proterra Board to issue any or all shares of New Proterra Preferred Stock in one or more classes or series, with such terms and conditions as may be expressly determined by the New Proterra Board and as may be permitted by the DGCL;

•        to authorize the removal of the ability of New Proterra stockholders to take action by written consent in lieu of a meeting; and

•        to amend and restate the Existing Governing Documents and authorize all other changes necessary or, as mutually agreed in good faith by ArcLight and Proterra, desirable in connection with the replacement of Existing Governing Documents with the Proposed Governing Documents as part of the Domestication;

•        a proposal to approve by ordinary resolution the issuance of shares of New Proterra Common Stock in connection with the Business Combination and the PIPE Financing in compliance with the Nasdaq Listing Rules;

•        a proposal to approve and adopt by ordinary resolution the Equity Incentive Plan;

•        a proposal to approve and adopt by ordinary resolution the ESPP; and

•        a proposal to approve by ordinary resolution the adjournment of the extraordinary general meeting to a later date or dates, if necessary, to, among other things, permit further solicitation and vote of proxies in the event that there are insufficient votes for the approval of one or more proposals at the extraordinary general meeting.

If our shareholders do not approve each of the Condition Precedent Proposals, then unless certain conditions in the Merger Agreement are waived by the applicable parties to the Merger Agreement, the Merger Agreement could terminate and the Business Combination may not be consummated.

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For more information, please see “Business Combination Proposal,” “Domestication Proposal,” “Governing Documents Proposals,” “Nasdaq Proposal,” “Equity Incentive Plan Proposal,” “Employee Stock Purchase Plan Proposal” and “Adjournment Proposal.”

ArcLight will hold the extraordinary general meeting to consider and vote upon these proposals. This proxy statement/prospectus contains important information about the Business Combination and the other matters to be acted upon at the extraordinary general meeting. Shareholders of ArcLight should read it carefully.

After careful consideration, the ArcLight Board has determined that the Business Combination Proposal, the Domestication Proposal, each of the Governing Documents Proposals, the Nasdaq Proposal, the Equity Incentive Plan Proposal, the Employee Stock Purchase Plan Proposal and the Adjournment Proposal are in the best interests of ArcLight and its shareholders and unanimously recommends that you vote or give instruction to vote “FOR” each of those proposals.

The existence of financial and personal interests of one or more of ArcLight’s directors may result in a conflict of interest on the part of such director(s) between what he, she or they may believe is in the best interests of ArcLight and its shareholders and what he, she or they may believe is best for himself, herself or themselves in determining to recommend that shareholders vote for the proposals. In addition, ArcLight’s officers have interests in the Business Combination that may conflict with your interests as a shareholder. See the section entitled “Business Combination Proposal — Interests of ArcLight’s Directors and Executive Officers in the Business Combination” for a further discussion of these considerations.

Q:     Why is ArcLight proposing the Business Combination?

A:     ArcLight is a blank check company incorporated on July 28, 2020 as a Cayman Islands exempted entity for the purpose of effecting a merger, share exchange, asset acquisition, share purchase, reorganization or similar business combination with one or more businesses or entities, which we refer to throughout this prospectus as our initial business combination. Based on ArcLight’s business activities, it is a “shell company” as defined under the Exchange Act because it has no operations and nominal assets consisting almost entirely of cash.

ArcLight has identified several general criteria and guidelines to evaluate prospective acquisition opportunities. ArcLight has sought to acquire a business or company that: (i) exhibits, or has the potential to develop, fundamentally sound financial performance, with visibility into revenue and cash flow growth and relatively predictable future financial performance; (ii) is an active market participant in the global development of the clean energy industry, continued decarbonization of the industrial, government and consumer spaces, and/or broader transition toward a sustainable economic model; (iii) targets large addressable markets with long-term tailwinds and low risk of obsolescence; (iv) has a defensible market position with differentiated product offerings, technology, assets, distribution channels, supply chain capabilities or other sustainable competitive advantages; (v) can serve as a platform for both organic and acquisitive growth; (vi) is led by an experienced management team with a proven track record and complementary capabilities, or is open to enhancing the existing management team’s strengths with additional talent through ArcLight’s network; and (vii) embraces the potential to utilize ArcLight’s industry experience, as well as operating, strategic, financing and M&A capabilities to maximize the value to shareholders.

Based on its due diligence investigations of Proterra and the industry in which it operates, including the financial and other information provided by Proterra in the course of negotiations, the ArcLight Board believes that Proterra meets the general criteria and guidelines listed above. However, there is no assurance of this. See “Business Combination Proposal — The ArcLight Board’s Reasons for the Business Combination.”

Although the ArcLight Board believes that the Business Combination with Proterra presents a unique business combination opportunity and is in the best interests of ArcLight and its shareholders, the board of directors did consider certain potentially material negative factors in arriving at that conclusion. These factors are discussed in greater detail in the sections entitled “Business Combination Proposal — The ArcLight Board’s Reasons for the Business Combination” and “Risk Factors — Risks Related to the Business Following the Business Combination.”

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Q:     Did the ArcLight Board obtain a third-party valuation or fairness opinion in determining whether or not to proceed with the Business Combination?

A:     No. The ArcLight Board did not obtain a third-party valuation or fairness opinion in connection with its determination to approve the Business Combination. However, ArcLight’s management, the members of the ArcLight Board and other representatives of ArcLight have substantial experience in evaluating the operating and financial merits of companies engaged in the energy industry and reviewed certain financial information of Proterra and compared it to certain publicly traded companies, selected based on the experience and the professional judgment of ArcLight’s management team, which enabled them to make the necessary analyses and determinations regarding the Business Combination. Accordingly, investors will be relying solely on the judgment of ArcLight’s management and the ArcLight Board in valuing Proterra’s business and assuming the risk that ArcLight’s management and the ArcLight Board may not have properly valued such business.

Q:     What will Proterra’s equityholders receive in return for the Business Combination with ArcLight?

A:     Following the consummation of the Domestication, on the Closing Date, Phoenix Merger Sub will merge with and into Proterra, with Proterra as the surviving company in the Merger and, after giving effect to the Merger, Proterra will be a wholly-owned subsidiary of ArcLight. In accordance with the terms and subject to the conditions of the Merger Agreement, at the Effective Time, (i) each share of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for 0.8925 shares of New Proterra Common Stock, (ii) each warrant and equity award of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for comparable warrants or equity awards that are exercisable for 0.8925 shares of New Proterra Common Stock, as applicable, and (iii) each Convertible Note that is not optionally converted immediately prior to the Effective Time will become convertible into shares of New Proterra Common Stock, in accordance with the terms of Convertible Note. In addition to the issuance of New Proterra Common Stock (based on the 0.8925 exchange ratio, referred to herein as the “Exchange Ratio”) as of Closing, in the event that the sale price of New Proterra Common Stock exceeds certain price thresholds for 20 out of any 30 consecutive trading days during the first five years following the Closing Date, up to an additional 22,809,500 shares of New Proterra Common Stock may be issued to certain Proterra Holders. For further details, see “Business Combination Proposal — Consideration to Proterra Holders in the Business Combination.

Q:     How will the combined company be managed following the business combination?

A:     Following the Closing, it is expected that the current management of Proterra will become the management of New Proterra, and the New Proterra Board will consist of up to nine (9) directors, which will be divided into three classes (Class I, II and III) with each consisting of three directors. Pursuant to the Merger Agreement, the New Proterra Board will consist of (i) eight (8) individuals designated by Proterra (all of whom are existing members of Proterra’s board of directors) and (ii) one director selected by the Sponsor. Please see the section entitled “Management of New Proterra Following the Business Combination” for further information.

Q:     What equity stake will current ArcLight shareholders and current equityholders of Proterra hold in New Proterra immediately after the consummation of the Business Combination?

A:     As of the date of this proxy statement/prospectus, there are 34,687,500 ordinary shares issued and outstanding, which includes an aggregate of 6,937,500 Class B ordinary shares held by the Initial Shareholders, including the Sponsor. In addition, as of the date of this proxy statement/prospectus, there is outstanding an aggregate of 21,425,000 warrants to acquire ordinary shares, comprised of 7,550,000 private placement warrants held by the Sponsor and 13,875,000 public warrants. Each whole warrant entitles the holder thereof to purchase one Class A ordinary share and, following the Domestication, will entitle the holder thereof to purchase one share of New Proterra Common Stock. Therefore, as of the date of this proxy statement/prospectus (without giving effect to the Business Combination and assuming that none of ArcLight’s outstanding public shares are redeemed in connection with the Business Combination), ArcLight’s fully diluted share capital, giving effect to the exercise of all of the private placement warrants and public warrants, would be 56,112,500 Class A ordinary shares.

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The following table illustrates varying ownership levels in New Proterra Common Stock immediately following the consummation of the Business Combination based on the varying levels of redemptions by the public shareholders and the following additional assumptions: (i) 164,863,846 shares of New Proterra Common Stock are issued to the Proterra Holders at Closing in a no redemption scenario and 167,512,081 shares of New Proterra Common Stock are issued to the Proterra Holders at Closing in a maximum redemption scenario; (ii) 41,500,000 shares of New Proterra Common Stock are issued in the PIPE Financing; and (iii) no ArcLight warrants to purchase New Proterra Common Stock that will be outstanding immediately following Closing have been exercised. The share totals in clause (i) of the prior sentence are calculated assuming that all outstanding warrants and vested, in-the-money equity awards are net exercised using a $10.00 per share value, based on vesting as of February 28, 2021, assuming the conversion of the principal balance of the Convertible Notes, and without taking into account the effect of accrued unpaid cash interest or paid-in-kind interest. See “Unaudited Pro Forma Condensed Combined Financial Information” for more details. If the actual facts differ from these assumptions, the ownership percentages in ArcLight will be different and totals may not add up to 100% due to rounding.

     

Share Ownership in
New Proterra
(Percentage of Outstanding Shares)

   

No
redemptions

 

Maximum redemptions

Proterra Holders(1)

 

68.6

%

 

77.8

%

PIPE Investors(2)

 

17.3

%

 

19.3

%

ArcLight public shareholders(3)

 

11.5

%

 

0.0

%

Initial Shareholders(4)

 

2.6

%

 

2.9

%

__________

(1)      Assumes that the number of shares of New Proterra Common Stock to be held by Proterra Holders is 164,863,846 shares in the no redemption scenario and 167,512,081 in the maximum redemption scenario. The shares to be issued for outstanding warrants, vested stock options and Convertible Notes are calculated on a cashless exercise basis, based on a deemed value of $10.00 per share, and as if converted at the Closing, and excludes the effect of accrued interest on the Convertible Notes. See “Unaudited Pro Forma Condensed Combined Financial Information” for more details. The number of vested options is calculated as of February 28, 2021.

(2)      Consists of 41,500,000 shares to be acquired in connection with the PIPE Financing, including 600,000 shares to be acquired by certain affiliates of ArcLight.

(3)      Includes (i) 25,000,000 shares issued in connection with ArcLight’s initial public offering and (ii) an additional 2,750,000 shares issued pursuant to the partial exercise by the underwriters of their over-allotment option in connection with ArcLight’s initial public offering.

(4)      Includes 6,257,750 shares of New Proterra Common Stock. Does not include 679,750 shares of New Proterra Common Stock received by the Sponsor at Closing, which are subject to forfeiture upon the failure to achieve certain price targets following the consummation of the Business Combination. Does not include 600,000 shares to be acquired by certain affiliates of ArcLight in the PIPE Financing.

For further details, see “Business Combination Proposal — Consideration to Proterra Holders in the Business Combination.”

Q:     Why is ArcLight proposing the Domestication?

A:     Our board of directors believes that there are significant advantages to us that will arise as a result of a change of our domicile to Delaware. Further, our board of directors believes that any direct benefit that the Delaware General Corporation Law (the “DGCL”) provides to a corporation also indirectly benefits its stockholders, who are the owners of the corporation. The board of directors believes that there are several reasons why transfer by way of continuation to Delaware is in the best interests of ArcLight and its shareholders, including, (i) the prominence, predictability and flexibility of the DGCL, (ii) Delaware’s well-established principles of corporate governance and (iii) the increased ability for Delaware corporations to attract and retain qualified directors, each of the foregoing are discussed in greater detail in the section entitled “Domestication Proposal — Reasons for the Domestication.”

To effect the Domestication, we will file an application for deregistration with the Cayman Islands Registrar of Companies, together with the necessary accompanying documents, and file a certificate of corporate domestication and a certificate of incorporation with the Secretary of State of the State of Delaware, under which we will be domesticated and continue as a Delaware corporation.

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The approval of the Domestication Proposal is a condition to closing the Business Combination under the Merger Agreement. The approval of the Domestication Proposal requires a special resolution under Cayman Islands law, being the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter. Abstentions and broker non-votes, while considered present for the purposes of establishing a quorum, will not count as votes cast at the extraordinary general meeting, and otherwise will have no effect on a particular proposal.

Q:     What is involved with the Domestication?

A:     The Domestication will require ArcLight to file certain documents in both the Cayman Islands and the State of Delaware. At the effective time of the Domestication, which will be the Closing Date, ArcLight will cease to be a company incorporated under the laws of the Cayman Islands and in connection with the Business Combination, ArcLight will continue as a Delaware corporation. The Articles of Association will be replaced by the Proposed Certificate of Incorporation and Proposed Bylaws and your rights as a shareholder will cease to be governed by the laws of the Cayman Islands and will be governed by Delaware law.

Q:     What amendments will be made to the Existing Governing Documents of ArcLight?

A:     The consummation of the Business Combination is conditional, among other things, on the Domestication. Accordingly, in addition to voting on the Business Combination, ArcLight’s shareholders also are being asked to consider and vote upon a proposal to approve the Domestication, and replace ArcLight’s Existing Governing Documents, in each case, under Cayman Islands law with the Proposed Governing Documents, in each case, under the DGCL, which differ from the Existing Governing Documents in the following material respects:

     

Existing Governing Documents

 

Proposed Governing Documents

Authorized Shares
(Governing Documents
Proposal A)

 

The share capital under the Existing Governing Documents is US$55,500 divided into 500,000,000 Class A ordinary shares of par value US$0.0001 per share, 50,000,000 Class B ordinary shares of par value US$0.0001 per share and 5,000,000 preference shares of par value US$0.0001 per share.

 

The Proposed Governing Documents authorize 500,000,000 shares of New Proterra Common Stock and 10,000,000 shares of New Proterra Preferred Stock.

   

See paragraph 5 of the Memorandum of Association.

 

See Article IV of the Proposed Certificate of Incorporation.

Authorize the Board of Directors to Issue Preferred Stock Without Stockholder Consent
(Governing Documents
Proposal B)

 

The Existing Governing Documents authorize the issuance of 5,000,000 preference shares with such designation, rights and preferences as may be determined from time to time by our board of directors. Accordingly, our board of directors is empowered under the Existing Governing Documents, without shareholder approval, to issue preference shares with dividend, or other distribution, voting, return of capital or other rights which could adversely affect the voting power or other rights of the holders of ordinary shares.

 

The Proposed Governing Documents authorize the board of directors to issue preferred stock from time to time in one or more series, and, with respect to each series, to establish the number of shares in each such series, to fix the designation, powers (including voting powers), preferences and relative, participating, optional or other special rights, if any, of each such series and any qualifications, limitations or restrictions thereof, and, subject to the rights of such series, and to increase or decrease the number of shares of any such series.

   

See paragraph 5 of the Memorandum of Association and Article 3 of the Articles of Association.

 

See Article IV, subsection 2 of the Proposed Certificate of Incorporation.

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Existing Governing Documents

 

Proposed Governing Documents

Shareholder/Stockholder Written Consent In Lieu of a Meeting
(Governing Documents
Proposal C
)

 

The Existing Governing Documents provide that resolutions may be passed by a vote in person, by proxy at a general meeting, or by unanimous written resolution.

 

The Proposed Governing Documents allow stockholders to vote in person or by proxy at a meeting of stockholders, but prohibit the ability of stockholders to act by written consent in lieu of a meeting.

   

See Articles 22 and 23 of our Articles of Association.

 

See Article VIII subsection 1 of the Proposed Certificate of Incorporation.

Corporate Name
(Governing Documents
Proposal D
)

 

The Existing Governing Documents provide the name of the company is “ArcLight Clean Transition Corp.”

See paragraph 1 of our Memorandum of Association.

 

The Proposed Governing Documents will provide that the name of the corporation will be “Proterra Inc”

See Article I of the Proposed Certificate of Incorporation.

Perpetual Existence
(Governing Documents
Proposal D
)

 

The Existing Governing Documents provide that if we do not consummate a business combination (as defined in the Existing Governing Documents) by September 25, 2022 (twenty-fourth months after the closing of ArcLight’s initial public offering), ArcLight will cease all operations except for the purposes of winding up and will redeem the shares issued in ArcLight’s initial public offering and liquidate its trust account.

 

The Proposed Governing Documents do not include any provisions relating to New Proterra’s ongoing existence; the default under the DGCL will make New Proterra’s existence perpetual.

   

See Article 49 of our Articles of Association.

 

This is the default rule under the DGCL.

   

Exclusive Forum
(Governing Documents
Proposal D
)

 

The Existing Governing Documents do not contain a provision adopting an exclusive forum for certain shareholder litigation.

 

The Proposed Governing Documents adopt Delaware as the exclusive forum for certain stockholder litigation and the federal courts of the United States as the exclusive forum for litigation arising out of the Securities Act or the Exchange Act.

           

See Article IX of the Proposed Certificate of Incorporation and Article XI of the Proposed Bylaws.

   

Provisions Related to Status as Blank Check Company
(
Governing Documents
Proposal D
)

 

The Existing Governing Documents set forth various provisions related to our status as a blank check company prior to the consummation of a business combination.

 

The Proposed Governing Documents do not include such provisions related to our status as a blank check company, which no longer will apply upon consummation of the Business Combination, as we will cease to be a blank check company at such time.

       

See Article 49 of our Articles of Association.

   

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Q:     How will the Domestication affect my ordinary shares, warrants and units?

A:     In connection with the Domestication, on the Closing Date prior to the Effective Time, (i) each issued and outstanding Class A ordinary share will convert automatically by operation of law, on a one-for-one basis, into shares of New Proterra Common Stock; (ii) each issued and outstanding Class B ordinary share of ArcLight will convert automatically by operation of law, on a one-for-one basis, into shares of New Proterra Common Stock, (iii) each issued and outstanding warrant to purchase Class A ordinary shares of ArcLight will automatically represent the right to purchase one share of New Proterra Common Stock at an exercise price of $11.50 per share of New Proterra Common Stock on the terms and conditions set forth in the warrant agreement; and (iv) each issued and outstanding unit of ArcLight that has not been previously separated into the underlying Class A ordinary share and underlying warrant upon the request of the holder thereof, will be cancelled and will entitle the holder thereof to one share of New Proterra Common Stock and one-half of one warrant, with a whole warrant representing the right to acquire one share of New Proterra Common Stock. See “Domestication Proposal.

In accordance with the terms and subject to the conditions of the Merger Agreement, at the Effective Time, (i) each share of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for 0.8925 shares of New Proterra Common Stock, (ii) each warrant and equity award of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for comparable warrants or equity awards that are exercisable for 0.8925 shares of New Proterra Common Stock, as applicable, and (iii) each Convertible Note that is not optionally converted immediately prior to the Effective Time will become convertible into shares of New Proterra Common Stock, in accordance with the terms of the Convertible Notes. For further details, see “Business Combination Proposal — Consideration to Proterra Holders in the Business Combination.”

Q:     What are the U.S. federal income tax consequences of the Domestication?

A:     As discussed more fully under “U.S. Federal Income Tax Considerations,” the Domestication should constitute a tax-deferred reorganization within the meaning of Section 368(a)(l)(F) of the U.S. Internal Revenue Code of 1986, as amended (the “Code”). However, due to the absence of direct guidance on the application of Section 368(a)(1)(F) of the Code to the facts and circumstances relating to ArcLight, this result is not entirely clear. In the case of a transaction, such as the Domestication, that should qualify as a tax-deferred reorganization within the meaning of Section 368(a)(1)(F) of the Code, U.S. Holders (as defined in “U.S. Federal Income Tax Considerations — U.S. Holders” below) will be subject to Section 367(b) of the Code and, as a result of the Domestication:

•        a U.S. Holder that holds public shares that have a fair market value of less than $50,000 on the date of the Domestication generally will not recognize any gain or loss and will not be required to include any part of ArcLight’s earnings in income;

•        a U.S. Holder that holds public shares that have a fair market value of $50,000 or more and that, on the date of the Domestication, owns (actually and constructively) less than 10% of the total combined voting power of all classes of our stock entitled to vote and less than 10% of the total value of all classes of our stock generally will recognize gain (but not loss) on the exchange of public shares for shares of New Proterra Common Stock pursuant to the Domestication. As an alternative to recognizing gain, such U.S. Holder may file an election to include in income as a deemed dividend the “all earnings and profits amount” (as defined in the Treasury Regulations under Section 367(b) of the Code) attributable to its public shares provided certain other requirements are satisfied; and

•        a U.S. Holder that holds public shares have a fair market value of $50,000 or more and that, on the date of the Domestication, owns (actually or constructively) 10% or more of the total combined voting power of all classes of our stock entitled to vote or 10% or more of the total value of all classes of our stock generally will be required to include in income as a deemed dividend the “all earnings and profits amount” attributable to its public shares provided certain other requirements are satisfied. Any such

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U.S. Holder that is a corporation may, under certain circumstances, effectively be exempt from taxation on a portion or all of the deemed dividend pursuant to Section 245A of the Code (commonly referred to as the participation exemption).

ArcLight does not expect to have significant cumulative earnings and profits through the date of the Domestication.

ArcLight believes that it is likely classified as a PFIC. If ArcLight is a PFIC, a U.S. Holder of public shares may, in certain circumstances, still recognize gain (but not loss) upon the exchange of its public shares or public warrants for New Proterra Common Stock or New Proterra public warrants pursuant to the Domestication under the “passive foreign investment company” (“PFIC”) rules of the Code equal to the excess, if any, of the fair market value of the shares of New Proterra Common Stock or New Proterra public warrants received in the Domestication over the U.S. Holder’s adjusted tax basis in the corresponding public shares or public warrants surrendered in exchange therefor. The tax on any such gain so recognized would be imposed at the rate applicable to ordinary income and an interest charge would apply. For a more complete discussion of the potential application of the PFIC rules to U.S. Holders as a result of the Domestication, see the discussion in the section entitled “U.S. Federal Income Tax Considerations — U.S. Holders — PFIC Considerations.”

Additionally, the Domestication may cause non-U.S. Holders (as defined in “U.S. Federal Income Tax Considerations — Non-U.S. Holders”) to become subject to U.S. federal income withholding taxes on any dividends paid in respect of such non-U.S. Holder’s shares of New Proterra Common Stock after the Domestication.

The tax consequences of the Domestication are complex and will depend on a holder’s particular circumstances. All holders are urged to consult their tax advisor on the tax consequences to them of the Domestication, including the applicability and effect of U.S. federal, state, local and foreign income and other tax laws. For a more complete discussion of the U.S. federal income tax considerations of the Domestication, see “U.S. Federal Income Tax Considerations.

Q:     Do I have redemption rights?

A:     If you are a holder of public shares, you have the right to request that we redeem all or a portion of your public shares for cash provided that you follow the procedures and deadlines described elsewhere in this proxy statement/prospectus. Public shareholders may elect to redeem all or a portion of the public shares held by them regardless of if or how they vote in respect of the Business Combination Proposal. If you wish to exercise your redemption rights, please see the answer to the next question: “How do I exercise my redemption rights?

Notwithstanding the foregoing, a public shareholder, together with any affiliate of such public shareholder or any other person with whom such public shareholder is acting in concert or as a “group” (as defined in Section 13(d)(3) of the Exchange Act), will be restricted from redeeming its public shares with respect to more than an aggregate of 15% of the public shares. Accordingly, if a public shareholder, alone or acting in concert or as a group, seeks to redeem more than 15% of the public shares, then any such shares in excess of that 15% limit would not be redeemed for cash and such shares would be converted into the merger consideration in connection with the Business Combination.

The Sponsor has agreed to waive its redemption rights with respect to all of its ordinary shares in connection with the consummation of the Business Combination. Such shares will be excluded from the pro rata calculation used to determine the per-share redemption price.

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Q:     How do I exercise my redemption rights?

A:     In connection with the proposed Business Combination, pursuant to the Existing Governing Documents, ArcLight’s public shareholders may request that ArcLight redeem all or a portion of such public shares for cash if the Business Combination is consummated. If you are a public shareholder and wish to exercise your right to redeem the public shares, you must:

(i)     (a) hold public shares or (b) if you hold public shares through units, you elect to separate your units into the underlying public shares and public warrants prior to exercising your redemption rights with respect to the public shares;

(ii)    submit a written request to Continental, ArcLight’s transfer agent, in which you (i) request that we redeem all or a portion of your public shares for cash, and (ii) identify yourself as the beneficial holder of the public shares and provide your legal name, phone number and address; and

(iii)   deliver your public shares to Continental, our transfer agent, physically or electronically through The Depository Trust Company (“DTC”).

Holders must complete the procedures for electing to redeem their public shares in the manner described above prior to           ,            Time, on           , 2021 (two business days before the extraordinary general meeting) in order for their shares to be redeemed.

The address of Continental, ArcLight’s transfer agent, is listed under the question “Who can help answer my questions?” below.

Holders of units must elect to separate the units into the underlying public shares and public warrants prior to exercising redemption rights with respect to the public shares. Public holders that hold their units in an account at a brokerage firm or bank, must notify their broker or bank that they elect to separate the units into the underlying public shares and public warrants, or if a holder holds units registered in its own name, the holder must contact Continental, our transfer agent, directly and instruct them to do so.

Public shareholders will be entitled to request that their public shares be redeemed for a pro rata portion of the amount then on deposit in the trust account as of two business days prior to the consummation of the Business Combination including interest earned on the funds held in the trust account and not previously released to us (net of taxes payable). For illustrative purposes, this would have amounted to approximately $10.56 per issued and outstanding public share, based on 26,290,616 shares subject to possible redemption as of December 31, 2020. However, the proceeds deposited in the trust account could become subject to the claims of our creditors, if any, which could have priority over the claims of our public shareholders, regardless of whether such public shareholders vote or, if they do vote, irrespective of if they vote for or against the Business Combination Proposal. Therefore, the per share distribution from the trust account in such a situation may be less than originally expected due to such claims. Whether you vote, and if you do vote irrespective of how you vote, on any proposal, including the Business Combination Proposal, will have no impact on the amount you will receive upon exercise of your redemption rights. It is expected that the funds to be distributed to public shareholders electing to redeem their public shares will be distributed promptly after the consummation of the Business Combination.

Any request for redemption, once made by a holder of public shares, may be withdrawn at any time up to the time the vote is taken with respect to the Business Combination Proposal at the extraordinary general meeting. If you deliver your shares for redemption to Continental, our transfer agent, and later decide prior to the extraordinary general meeting not to elect redemption, you may request that our transfer agent return the shares (physically or electronically) to you. You may make such request by contacting Continental, our transfer agent, at the phone number or address listed at the end of this section.

Any corrected or changed written exercise of redemption rights must be received by Continental, our transfer agent, prior to the vote taken on the Business Combination Proposal at the extraordinary general meeting. No request for redemption will be honored unless the holder’s public shares have been delivered (either physically or electronically) to Continental, our transfer agent, at least two business days prior to the vote at the extraordinary general meeting.

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If a holder of public shares properly makes a request for redemption and the public shares are delivered as described above, then, if the Business Combination is consummated, we will redeem the public shares for a pro rata portion of funds deposited in the trust account, calculated as of two business days prior to the consummation of the Business Combination. The redemption takes place following the Domestication and, accordingly, it is shares of New Proterra Common Stock that will be redeemed immediately after consummation of the Business Combination.

If you are a holder of public shares and you exercise your redemption rights, such exercise will not result in the loss of any warrants that you may hold.

Q:     If I am a holder of units, can I exercise redemption rights with respect to my units?

A:     No. Holders of issued and outstanding units must elect to separate the units into the underlying public shares and public warrants prior to exercising redemption rights with respect to the public shares. If you hold your units in an account at a brokerage firm or bank, you must notify your broker or bank that you elect to separate the units into the underlying public shares and public warrants, or if you hold units registered in your own name, you must contact Continental, our transfer agent, directly and instruct them to do so. The redemption rights include the requirement that a holder must identify itself in writing as a beneficial holder and provide its legal name, phone number and address to Continental in order to validly redeem its shares. You are requested to cause your public shares to be separated and delivered to Continental, our transfer agent, by             ,              Time, on               , 2021 (two business days before the extraordinary general meeting) in order to exercise your redemption rights with respect to your public shares.

Q:     What are the U.S. federal income tax consequences of exercising my redemption rights?

A:     We expect that a U.S. Holder (as defined in “U.S. Federal Income Tax Considerations — U.S. Holders”) that exercises its redemption rights to receive cash from the trust account in exchange for its shares of New Proterra Common Stock will generally be treated as selling such shares of New Proterra Common Stock resulting in the recognition of capital gain or loss. There may be certain circumstances in which the redemption may be treated as a distribution for U.S. federal income tax purposes depending on the amount of shares of New Proterra Common Stock that such U.S. Holder owns or is deemed to own (including through the ownership of warrants) prior to and following the redemption. For a more complete discussion of the U.S. federal income tax considerations of an exercise of redemption rights, see “U.S. Federal Income Tax Considerations.

Additionally, because the Domestication will occur immediately prior to the redemption by any public shareholder, U.S. Holders exercising redemption rights will be subject to the potential tax consequences of Section 367(b) of the Code and the tax rules relating to PFICs. The tax consequences of the exercise of redemption rights, including pursuant to Section 367(b) of the Code and the PFIC rules, are discussed more fully below under “U.S. Federal Income Tax Considerations — U.S. Holders.” All holders of our public shares considering exercising their redemption rights are urged to consult their tax advisor on the tax consequences to them of an exercise of redemption rights, including the applicability and effect of U.S. federal, state, local and foreign income and other tax laws.

Q:     What happens to the funds deposited in the trust account after consummation of the Business Combination?

A:     Following the closing of ArcLight’s initial public offering, an amount equal to $277,500,000 ($10.00 per unit) of the net proceeds from our initial public offering and the sale of the private placement warrants was placed in the trust account. As of December 31, 2020, funds in the trust account totaled approximately $277,547,390, all of which were held in U.S. treasury securities. These funds will remain in the trust account, except for the withdrawal of interest to pay taxes, if any, until the earliest of (i) the completion of a business combination (including the closing of the Business Combination) or (ii) the redemption of all of the public shares if we are unable to complete a business combination by September 25, 2022 (unless such date is extended in accordance with the Existing Governing Documents), subject to applicable law.

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If our initial business combination is paid for using equity or debt securities or not all of the funds released from the trust account are used for payment of the consideration in connection with our initial business combination or used for redemptions or purchases of the public shares, we may apply the balance of the cash released to us from the trust account for general corporate purposes, including for maintenance or expansion of operations of New Proterra, the payment of principal or interest due on indebtedness incurred in completing our Business Combination, to fund the purchase of other companies or for working capital. See “Summary of the Proxy Statement/Prospectus — Sources and Uses of Funds for the Business Combination.”

Q:     What happens if a substantial number of the public shareholders vote in favor of the Business Combination Proposal and exercise their redemption rights?

A:     Our public shareholders are not required to vote “FOR” the Business Combination in order to exercise their redemption rights. Accordingly, the Business Combination may be consummated even though the funds available from the trust account and the number of public shareholders are reduced as a result of redemptions by public shareholders, subject to the satisfaction or waiver of the Aggregate Transaction Proceeds Condition.

In no event will ArcLight redeem public shares in an amount that would cause our net tangible assets (as determined in accordance with Rule 3a51-1(g)(1) of the Exchange Act) to be less than $5,000,001 after giving effect to the transactions contemplated by the Merger Agreement and the PIPE Financing.

Additionally, as a result of redemptions, the trading market for the New Proterra Common Stock may be less liquid than the market for the public shares was prior to consummation of the Business Combination and we may not be able to meet the listing standards for Nasdaq or another national securities exchange.

Q:     What conditions must be satisfied to complete the Business Combination?

A:     The consummation of the Business Combination is conditioned upon, among other things, (i) the approval by the ArcLight shareholders of the Condition Precedent Proposals being obtained; (ii) the applicable waiting period under the HSR Act relating to the Business Combination having expired or been terminated; (iii) the aggregate cash proceeds from ArcLight’s trust account, together with the proceeds from the PIPE Financing, equaling no less than $300,000,000 as a condition to ArcLight’s obligation to close or $350,000,000 as a condition to Proterra’s obligation to close (in each case, after deducting any amounts paid to ArcLight’s stockholders that exercise their redemption rights in connection with the Business Combination and net of unpaid transaction expenses incurred or subject to reimbursement by ArcLight); (iv) the New Proterra Common Stock to be issued in connection with the Business Combination having been approved for listing on Nasdaq; and (v) receipt of fully executed copies of the Debt Facility Amendment (as defined in the Merger Agreement) from Proterra’s first-lien debtholders in support of the Business Combination. Therefore, unless these conditions are waived by the applicable parties to the Merger Agreement, the Merger Agreement could terminate and the Business Combination may not be consummated.

For more information about conditions to the consummation of the Business Combination, see “Business Combination Proposal — Conditions to Closing of the Business Combination.”

Q:     When do you expect the Business Combination to be completed?

A:     It is currently expected that the Business Combination will be consummated in the second quarter of 2021. This date depends, among other things, on the approval of the proposals to be put to ArcLight shareholders at the extraordinary general meeting. However, such extraordinary general meeting could be adjourned if the Adjournment Proposal is adopted by our shareholders at the extraordinary general meeting and we elect to adjourn the extraordinary general meeting to a later date or dates to consider and vote upon a proposal to approve by ordinary resolution the adjournment of the extraordinary general meeting to a later date or dates (A) to the extent necessary to ensure that any required supplement or amendment to the accompanying proxy statement/prospectus is provided to ArcLight shareholders or, if as of the time for which the extraordinary general meeting is scheduled, there are insufficient ArcLight ordinary shares represented (either in person or by proxy) to constitute a quorum necessary to conduct business at the extraordinary general meeting, (B) in order to solicit additional proxies from ArcLight shareholders in favor of one or more of the proposals at the

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extraordinary general meeting or (C) if ArcLight shareholders redeem an amount of public shares such that the Aggregate Transaction Proceeds Condition would not be satisfied. For a description of the conditions for the completion of the Business Combination, see “Business Combination Proposal — Conditions to Closing of the Business Combination.”

Q:     What happens if the Business Combination is not consummated?

A:     ArcLight will not complete the Domestication to Delaware unless all other conditions to the consummation of the Business Combination have been satisfied or waived by the parties in accordance with the terms of the Merger Agreement. If ArcLight is not able to consummate the Business Combination with Proterra nor able to complete another business combination by September 25, 2022, in each case, as such date may be extended pursuant to our Existing Governing Documents, we will (i) cease all operations except for the purpose of winding up; (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the trust account, including interest earned on the funds held in the trust account and not previously released to us to pay our income taxes, if any (less up to $100,000 of interest to pay dissolution expenses) divided by the number of the then-outstanding public shares, which redemption will completely extinguish public shareholders’ rights as shareholders (including the right to receive further liquidation distributions, if any); and (iii) as promptly as reasonably possible following such redemption, subject to the approval of our remaining shareholders and our board of directors, liquidate and dissolve, subject in the case of clauses (ii) and (iii), to our obligations under Cayman Islands law to provide for claims of creditors and the requirements of other applicable law.

Q:     Do I have appraisal rights in connection with the proposed Business Combination and the proposed Domestication?

A:     Neither our shareholders nor our warrant holders have appraisal rights in connection with the Business Combination or the Domestication under the Cayman Islands Companies Law or under the DGCL.

Q:     What do I need to do now?

A:     We urge you to read this proxy statement/prospectus, including the Annexes and the documents referred to herein, carefully and in their entirety and to consider how the Business Combination will affect you as a shareholder and/or warrant holder. Our shareholders should then vote as soon as possible in accordance with the instructions provided in this proxy statement/prospectus and on the enclosed proxy card.

Q:     How do I vote?

A:     If you hold your shares in “street name,” which means your shares are held of record by a broker, bank or nominee, and were a holder of record of ordinary shares on               , 2021, the record date for the extraordinary general meeting, you may vote with respect to the proposals in person or virtually at the extraordinary general meeting, or by completing, signing, dating and returning the enclosed proxy card in the postage-paid envelope provided. For the avoidance of doubt, the record date does not apply to ArcLight shareholders that hold their shares in registered form and are registered as shareholders in ArcLight’s register of members. All holders of shares in registered form on the day of the extraordinary general meeting are entitled to vote at the extraordinary general meeting.

Q:     If my shares are held in “street name,” will my broker, bank or nominee automatically vote my shares for me?

A:     No. If your shares are held in a stock brokerage account or by a bank or other nominee, you are considered the “beneficial holder” of the shares held for you in what is known as “street name.” If this is the case, this proxy statement/prospectus may have been forwarded to you by your brokerage firm, bank or other nominee, or its agent. As the beneficial holder, you have the right to direct your broker, bank or other nominee as to how to vote your shares. If you do not provide voting instructions to your broker on a particular proposal on which your broker does not have discretionary authority to vote, your shares will not be voted on that proposal. This is called a “broker non-vote.” Abstentions and broker non-votes, while considered present for the purposes of

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establishing a quorum, will not count as votes cast at the extraordinary general meeting, and otherwise will have no effect on a particular proposal. If you decide to vote, you should provide instructions to your broker, bank or other nominee on how to vote in accordance with the information and procedures provided to you by your broker, bank or other nominee.

Q:     When and where will the extraordinary general meeting be held?

A:     The extraordinary general meeting will be held at               ,         Time, on           , 2021 at the offices of Kirkland & Ellis LLP located at             , unless the extraordinary general meeting is adjourned. As part of our precautions regarding COVID-19, we also intend to hold the extraordinary general meeting through a “virtual” or online method. We will post the details for such meeting on our website that will also be filed with the SEC as proxy material. Only shareholders who held ordinary shares of ArcLight at the close of business on the Record Date will be entitled to vote at the Shareholders Meeting. We plan to announce any such updates in a press release filed with the SEC and on our proxy website at           , and we encourage you to check this website prior to the meeting if you plan to attend.

Q:     What impact will the COVID-19 Pandemic have on the Business Combination?

A:     Given the ongoing and dynamic nature of the circumstances, it is difficult to predict the impact of the COVID-19 outbreak on the business of ArcLight and Proterra, and there is no guarantee that efforts by ArcLight and Proterra to address the adverse impacts of the COVID-19 will be effective. The extent of such impact will depend on future developments, which are highly uncertain and cannot be predicted, including new information which may emerge concerning the severity of the COVID-19 and actions taken to contain the COVID-19 or its impact, among others. If ArcLight or Proterra are unable to recover from a business disruption on a timely basis, the Business Combination and New Proterra’s business, financial condition and results of operations following the completion of the Business Combination would be adversely affected. The Business Combination may also be delayed and adversely affected by the COVID-19 outbreak and become more costly. Each of ArcLight and Proterra may also incur additional costs to remedy damages caused by any such disruptions, which could adversely affect its financial condition and results of operations.

Q:     Who is entitled to vote at the extraordinary general meeting?

A:     We have fixed           , 2021 as the record date for the extraordinary general meeting. If you were a shareholder of ArcLight at the close of business on the record date, you are entitled to vote on matters that come before the extraordinary general meeting. However, a shareholder may only vote his or her shares if he or she is present in person or is represented by proxy at the extraordinary general meeting.

Q:     How many votes do I have?

A:     ArcLight shareholders are entitled to one vote at the extraordinary general meeting for each ordinary share held of record as of the record date. As of the close of business on the record date for the extraordinary general meeting, there were 34,687,500 ordinary shares issued and outstanding, of which 27,750,000 were issued and outstanding public shares.

Q:     What constitutes a quorum?

A:     A quorum of ArcLight shareholders is necessary to hold a valid meeting. A quorum will be present at the extraordinary general meeting if one or more shareholders who together hold not less than a majority of the issued and outstanding ordinary shares entitled to vote at the extraordinary general meeting are represented in person or by proxy at the extraordinary general meeting. As of the record date for the extraordinary general meeting, 17,343,751 ordinary shares would be required to achieve a quorum.

Q:     What vote is required to approve each proposal at the extraordinary general meeting?

A:     The following votes are required for each proposal at the extraordinary general meeting:

(i)     Business Combination Proposal: The approval of the Business Combination Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

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(ii)    Domestication Proposal: The approval of the Domestication Proposal requires a special resolution under Cayman Islands law, being the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(iii)   Governing Documents Proposals: The separate approval of each of the Governing Documents Proposals requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter, other than Proposal D, which requires a special resolution under Cayman Islands law, being the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(iv)   Nasdaq Proposal: The approval of the Nasdaq Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(v)    Equity Incentive Plan Proposal: The approval of the Equity Incentive Plan Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(vi)   Employee Stock Purchase Plan Proposal: The approval of the Employee Stock Purchase Plan Proposal requires an ordinary resolution, being the affirmative vote of a majority of the ordinary shares represented in person or by proxy and entitled to vote thereon and who vote at the extraordinary general meeting.

(vii)  Adjournment Proposal: The approval of the Adjournment Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

As of the record date, ArcLight had 34,687,500 ordinary shares issued and outstanding. ArcLight shareholders are entitled to one vote at the extraordinary general meeting for each ordinary share held of record as of the record date. 6,937,500 ordinary shares are subject to the Sponsor Support Agreement, pursuant to which the Initial Shareholders have agreed to vote all of their shares in favor of the Business Combination. 27,750,000 ordinary shares are not subject to the Sponsor Support Agreement. For additional information regarding the Sponsor Support Agreement, see “Business Combination Proposal — Related Agreements — Transaction Support Agreements.”

Assuming all holders that are entitled to vote on such matter vote all of their ordinary shares in person or by proxy, 17,343,751 shares, of which 10,406,251 shares are not subject to the Sponsor Support Agreement, will need to be voted in favor of each of the Business Combination Proposal, the Governing Documents Proposals (other than Proposal D), the Nasdaq Proposal, the Equity Incentive Plan Proposal, the Employee Stock Purchase Plan Proposal and the Adjournment Proposal in order to approve each of the Business Combination Proposal, the Governing Documents Proposals, the Nasdaq Proposal, the Equity Incentive Plan Proposal, the Employee Stock Purchase Plan Proposal and the Adjournment Proposal.

Assuming all holders that are entitled to vote on such matter vote all of their ordinary shares in person or by proxy, 23,125,000 shares, of which 16,187,500 shares are not subject to the Sponsor Support Agreement, will need to be voted in favor of each of the Domestication Proposal and Proposal D of the Governing Documents Proposals in order to approve the such proposals.

Q:     What are the recommendations of the ArcLight Board?

A:     The ArcLight Board believes that the Business Combination Proposal and the other proposals to be presented at the extraordinary general meeting are in the best interest of ArcLight and its shareholders and unanimously recommends that its shareholders vote “FOR” the Business Combination Proposal, “FOR” the Domestication

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Proposal, “FOR” each of the separate Governing Documents Proposals, “FOR” the Nasdaq Proposal, “FOR” the Equity Incentive Plan Proposal, “FOR” the Employee Stock Purchase Plan Proposal and “FOR” the Adjournment Proposal, in each case, if presented to the extraordinary general meeting.

The existence of financial and personal interests of one or more of ArcLight’s directors may result in a conflict of interest on the part of such director(s) between what he, she or they may believe is in the best interests of ArcLight and its shareholders and what he, she or they may believe is best for himself, herself or themselves in determining to recommend that shareholders vote for the proposals. In addition, ArcLight’s officers have interests in the Business Combination that may conflict with your interests as a shareholder. See the section entitled “Business Combination Proposal — Interests of ArcLight’s Directors and Executive Officers in the Business Combination” for a further discussion of these considerations.

Q:     How do the Sponsor and the other Initial Shareholders intend to vote their shares?

A:     Unlike some other blank check companies in which the Initial Shareholders agree to vote their shares in accordance with the majority of the votes cast by the public shareholders in connection with an initial business combination, our Initial Shareholders have agreed to vote all their shares in favor of all the proposals being presented at the extraordinary general meeting. As of the date of this proxy statement/prospectus, our Initial Shareholders own 20.0% of the issued and outstanding ordinary shares.

At any time at or prior to the Business Combination, during a period when they are not then aware of any material nonpublic information regarding us or our securities, our Initial Shareholders, Proterra and/or their respective directors, officers, advisors or respective affiliates may purchase public shares from institutional and other investors who vote, or indicate an intention to vote, against any of the Condition Precedent Proposals, or execute agreements to purchase such shares from such investors in the future, or they may enter into transactions with such investors and others to provide them with incentives to acquire public shares or vote their public shares in favor of the Condition Precedent Proposals. Such a purchase may include a contractual acknowledgement that such shareholder, although still the record or beneficial holder of our shares, is no longer the beneficial owner thereof and therefore agrees not to exercise its redemption rights. In the event that our Initial Shareholders, Proterra and/or their directors, officers, advisors or respective affiliates who have agreed to vote in favor of this transaction purchase shares in privately negotiated transactions from public shareholders who have already elected to exercise their redemption rights, such selling shareholder would be required to revoke their prior elections to redeem their shares. The purpose of such share purchases and other transactions would be to increase the likelihood of satisfaction of the requirements that (i) the Business Combination Proposal, the Governing Documents Proposals, the Nasdaq Proposal, the Equity Incentive Plan Proposal, the Employee Stock Purchase Plan Proposal and the Adjournment Proposal are approved by the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter (ii) the Domestication Proposal is approved by the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter, (iii) otherwise limit the number of public shares electing to redeem their public shares and (iv) New Proterra’s net tangible assets (as determined in accordance with Rule 3a51-1(g)(1) of the Exchange Act) being at least $5,000,001 after giving effect to the transactions contemplated by the Merger Agreement and the PIPE Financing.

If such transactions are effected, the consequence could be to cause the Business Combination to be consummated in circumstances where such consummation could not otherwise occur. Purchases of shares by the persons described above would allow them to exert more influence over the approval of the proposals to be presented at the extraordinary general meeting and would likely increase the chances that such proposals would be approved. We will file or submit a Current Report on Form 8-K to disclose any material arrangements entered into or significant purchases made by any of the aforementioned persons that would affect the vote on the proposals to be put to the extraordinary general meeting or the redemption threshold.

Any such report will include descriptions of any arrangements entered into or significant purchases by any of the aforementioned persons.

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Q:     What interests do ArcLight’s current officers and directors have in the Business Combination?

A:     The Initial Shareholders, certain members of the ArcLight Board and our officers may have interests in the Business Combination that are different from or in addition to your interests. You should take these interests into account in deciding whether to approve the Business Combination. These interests include, among other things, the interests listed below:

•        the fact that our Initial Shareholders have agreed not to redeem any ordinary shares held by them in connection with a shareholder vote to approve a proposed initial business combination;

•        the fact that the Sponsor paid an aggregate of $25,000 for 8,625,000 Class B ordinary shares, 6,937,500 of which are currently owned by the Initial Shareholders. The 6,937,500 shares of New Proterra Common Stock that the Initial Shareholders will hold following the Business Combination, if unrestricted and freely tradable, and in the case of the shares held by the Sponsor, assuming all vesting conditions are satisfied, would have had an aggregate market value of $124,875,000 based upon the closing price of $18.00 per public share on the Nasdaq on April 6, 2021, the most recent closing price;

•        the fact that the Initial Shareholders and certain of ArcLight’s current officers have agreed to waive their rights to liquidating distributions from the trust account with respect to any ordinary shares (other than public shares) held by them if ArcLight fails to complete an initial business combination by September 25, 2022;

•        the fact that Sponsor paid $7,550,000 for 7,550,000 private placement warrants, which, if unrestricted and freely tradable, would have had an aggregate market value of $48,320,000 based upon the closing price of $6.40 per public warrant (although holders of the private placement warrants have certain rights that differ from the rights of holders of the public warrants) on Nasdaq on April 6, 2021, the most recent closing price, and the fact that the private placement warrants will expire worthless if a business combination is not consummated by September 25, 2022 (unless such date is extended in accordance with the Existing Governing Documents);

•        the fact that certain officers and Sponsor-affiliated directors of ArcLight are investors in ArcLight CTC Investors, which has agreed to subscribe for and purchase 600,000 shares of New Proterra Common Stock at $10.00 per share in the PIPE Financing on the same terms and conditions as the other PIPE Investors, for aggregate gross proceeds of $6,000,000. Such shares of New Proterra Common Stock would have had an estimated aggregate value of $10,800,000 based on the closing price of $18.00 per public share on Nasdaq on April 6, 2021, the most recent closing price;

•        the fact that the Amended and Restated Registration Rights Agreement will be entered into by the Sponsor and certain other affiliates of ArcLight;

•        the fact that, at the option of the Sponsor, and with the consent of Proterra, any amounts outstanding under any loan made by the Sponsor or any of its affiliates to ArcLight in an aggregate amount of up to $1,500,000 may be converted into warrants to purchase Class A ordinary shares in connection with the consummation of the Business Combination;

•        the continued indemnification of ArcLight’s directors and officers and the continuation of ArcLight’s directors’ and officers’ liability insurance after the Business Combination (i.e., a “tail policy”);

•        the fact that the Sponsor and ArcLight’s officers and directors will lose their entire investment in ArcLight and will not be reimbursed for any out-of-pocket expenses if an initial business combination is not consummated by September 25, 2022;

•        the fact that if the trust account is liquidated, including in the event ArcLight is unable to complete an initial business combination by September 25, 2022, the Sponsor has agreed to indemnify ArcLight to ensure that the proceeds in the trust account are not reduced below $10.00 per public share, or such lesser per public share amount as is in the trust account on the liquidation date, by the claims of prospective target businesses with which ArcLight has entered into an acquisition agreement or claims of any third party for services rendered or products sold to ArcLight, but only if such a vendor or target business has not executed a waiver of any and all rights to seek access to the trust account;

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•        the fact that ArcLight may be entitled to distribute or pay over funds held by ArcLight outside the Trust Account to the Sponsor or any of its Affiliates prior to the Closing; and

•        the fact that the Initial Shareholders entered into the Sponsor Support Agreement pursuant to which the original lock-up period to which our Sponsor and our directors and executive officers are subject was amended to remove such lock-up period, but only with respect to securities that are not held by the Sponsor.

These interests may influence our Board in making their recommendation that you vote in favor of the approval of the Business Combination. See the section entitled “Business Combination Proposal — Interests of ArcLight’s Directors and Executive Officers in the Business Combination” for a further discussion of these considerations.

Q:     What happens if I sell my ArcLight ordinary shares before the extraordinary general meeting?

A:     The record date for the extraordinary general meeting is earlier than the date of the extraordinary general meeting and earlier than the date that the Business Combination is expected to be completed. If you transfer your public shares after the applicable record date, but before the extraordinary general meeting, unless you grant a proxy to the transferee, you will retain your right to vote at such general meeting.

Q:     May I change my vote after I have mailed my signed proxy card?

A:     Yes. Shareholders may send a later-dated, signed proxy card to our general counsel at our address set forth below so that it is received by our general counsel prior to the vote at the extraordinary general meeting (which is scheduled to take place on               , 2021) or attend the extraordinary general meeting in person and vote. Shareholders also may revoke their proxy by sending a notice of revocation to our general counsel, which must be received by our general counsel prior to the vote at the extraordinary general meeting. However, if your shares are held in “street name” by your broker, bank or another nominee, you must contact your broker, bank or other nominee to change your vote.

Q:     What happens if I fail to take any action with respect to the extraordinary general meeting?

A:     If you fail to vote with respect to the extraordinary general meeting and the Business Combination is approved by shareholders and the Business Combination is consummated, you will become a stockholder and/or warrant holder of New Proterra. If you fail to vote with respect to the extraordinary general meeting and the Business Combination is not approved, you will remain a shareholder and/or warrant holder of ArcLight. However, if you fail to vote with respect to the extraordinary general meeting, you will nonetheless be able to elect to redeem your public shares in connection with the Business Combination.

Q:     What should I do if I receive more than one set of voting materials?

A:     Shareholders may receive more than one set of voting materials, including multiple copies of this proxy statement/prospectus and multiple proxy cards or voting instruction cards. For example, if you hold your shares in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold shares. If you are a holder of record and your shares are registered in more than one name, you will receive more than one proxy card. Please complete, sign, date and return each proxy card and voting instruction card that you receive in order to cast a vote with respect to all of your ordinary shares.

Q:     Who will solicit and pay the cost of soliciting proxies for the extraordinary general meeting?

A:     ArcLight will pay the cost of soliciting proxies for the extraordinary general meeting. ArcLight has engaged Morrow Sodali LLC (“Morrow”) as proxy solicitor to assist in the solicitation of proxies for the extraordinary general meeting. ArcLight has agreed to pay Morrow a fee of $30,000, plus disbursements, and will reimburse Morrow for its reasonable out-of-pocket expenses and indemnify Morrow and its affiliates against certain claims, liabilities, losses, damages and expenses. ArcLight will also reimburse banks, brokers and other custodians, nominees and fiduciaries representing beneficial owners of Class A ordinary shares for their expenses in forwarding soliciting materials to beneficial owners of Class A ordinary shares and in obtaining

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voting instructions from those owners. ArcLight’s directors and officers may also solicit proxies by telephone, by facsimile, by mail, on the Internet or in person. They will not be paid any additional amounts for soliciting proxies.

Q:     Where can I find the voting results of the extraordinary general meeting?

A:     The preliminary voting results will be announced at the extraordinary general meeting. ArcLight will publish final voting results of the extraordinary general meeting in a Current Report on Form 8-K within four business days after the extraordinary general meeting.

Q:     Who can help answer my questions?

A:     If you have questions about the Business Combination or if you need additional copies of the proxy statement/prospectus or the enclosed proxy card you should contact:

Morrow Sodali LLC
470 West Avenue

Stamford CT 06902

Individuals call toll-free: (800) 662-5200

Banks and brokers call: (203) 658-9400

Email: ACTC.info@investor.morrowsodali.com

You also may obtain additional information about ArcLight from documents filed with the SEC by following the instructions in the section entitled “Where You Can Find More Information; Incorporation by Reference.” If you are a holder of public shares and you intend to seek redemption of your public shares, you will need to deliver your public shares (either physically or electronically) to Continental, ArcLight’s transfer agent, at the address below prior to the extraordinary general meeting. Holders must complete the procedures for electing to redeem their public shares in the manner described above prior to         ,             Time, on           , 2021 (two business days before the extraordinary general meeting) in order for their shares to be redeemed. If you have questions regarding the certification of your position or delivery of your stock, please contact:

Continental Stock Transfer & Trust Company
1 State Street, 30th Floor
New York, New York 10004
Attention: Mark Zimkind
E-mail: mzimkind@continentalstock.com

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SUMMARY OF THE PROXY STATEMENT/PROSPECTUS

This summary highlights selected information from this proxy statement/prospectus and does not contain all of the information that is important to you. To better understand the proposals to be submitted for a vote at the extraordinary general meeting, including the Business Combination, you should read this proxy statement/prospectus, including the Annexes and other documents referred to herein, carefully and in their entirety. The Merger Agreement is the legal document that governs the Business Combination and the other transactions that will be undertaken in connection with the Business Combination. The Merger Agreement is also described in detail in this proxy statement/prospectus in the section entitled “Business Combination Proposal — The Merger Agreement.”

Business Summary

Unless otherwise indicated or the context otherwise requires, references in this Business Summary to “we,” “us,” “our” and other similar terms refer to Proterra prior to the Business Combination and to New Proterra and its consolidated subsidiaries after giving effect to the Business Combination.

Company Overview

Proterra’s mission is to advance electric vehicle technology to deliver the world’s best performing commercial vehicles.

Early in the 20th century, new methods of harnessing thermal energy, advancements in diesel engine technology, and a significant increase in manufacturing helped spark a revolution in transportation which unleashed billions of internal combustion engine trucks, buses, and cars into use around the world. Early in the 21st century, new methods of harnessing chemical energy, advancements in battery technology, and related advancements in manufacturing processes have begun to lay the groundwork for another revolution in transportation in which batteries can power vehicles with zero emissions.

Proterra is at the forefront of this revolution, with an integrated business model focused on providing end-to-end solutions that enable commercial vehicle electrification. Our commercial electric vehicle technology platform spans key elements of the electric vehicle ecosystem and provides solutions to some of the greatest difficulties facing fleet electrification.

While our business has historically been centered on the development and sale of electric transit buses, we are currently organized around three business lines, each of which addresses a critical component of the commercial vehicle electrification value proposition in a complementary and self-reinforcing manner:

•        Proterra Powered designs, develops, manufactures, sells, and integrates proprietary battery systems and electrification solutions into vehicles for global commercial vehicle original equipment manufacturer (“OEM”) customers serving the Class 3 to Class 8 vehicle segments, including delivery trucks, school buses, coach buses, construction and mining equipment, and other applications.

•        Proterra Transit designs, develops, manufactures, and sells electric transit buses as an OEM for North American public transit agencies, airports, universities, and other commercial transit fleets. Proterra Transit offers an ideal venue to showcase and validate our electric vehicle technology platform through rigorous daily use by a large group of sophisticated customers focused on meeting the wide-ranging needs of the diverse communities they serve.

•        Proterra Energy provides turnkey fleet-scale, high-power charging solutions and software services, ranging from fleet and energy management software-as-a-service, to fleet planning, hardware, infrastructure, installation, utility engagement, and charging optimization. These solutions are designed to optimize energy use and costs, and to provide vehicle-to-grid functionality.

The first application of Proterra Powered commercial vehicle electrification technology was through Proterra Transit’s heavy-duty electric transit bus, which we designed from the ground up for the North American market. Our industry experience, the performance of our transit buses, and compelling total cost of ownership has helped make us the leader in the U.S. electric transit bus market with over 50% market share of deliveries between 2012 and 2019 according to the National Transit Database. Our product offerings have allowed us to receive orders from over 130 unique customers across 43 states. With over 600 vehicles on the road, our electric transit buses have delivered

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over 18 million cumulative service miles spanning a wide spectrum of climates, conditions, altitudes and terrains. Operating battery-powered commercial vehicles can be difficult in varying climates and terrains, and the challenges we have faced with these operating conditions have led to product improvements, such as battery conditioning and our DuoPower drivetrain.

This experience has not only provided us a valuable opportunity to validate our products’ performance, fuel efficiency and maintenance costs to a demanding customer base but has also helped broaden our appeal as a supplier to OEMs in other commercial vehicle segments and geographies. Proterra Powered has partnered with Thomas Built Buses (a subsidiary of Daimler Trucks North America LLC), Freightliner Custom Chassis Corporation (a subsidiary of Daimler Trucks North America LLC), Van Hool NV, Optimal Electric Vehicles LLC, BusTech Pty Ltd. and Komatsu Ltd. in the school bus, step-van, motor coach and double-decker transit bus, shuttle bus, international transit bus, and construction and mining markets, respectively. Through December 31, 2020, Proterra Powered has delivered battery systems and electrification solutions for 130 vehicles to our OEM partner customers.

In addition, Proterra Energy has established itself as a leading commercial vehicle charging solution provider by helping fleet operators fulfill the high-power charging needs of commercial electric vehicles and optimize their energy usage, while meeting our customers’ space constraints and continuous service requirements. As of December 31, 2020, we had installed approximately 46 MW of charging infrastructure across more than 470 charge points throughout North America.

Through these three business lines, we have generated cumulative revenue of $501.4 million in the years ended December 31, 2020, 2019 and 2018. For the years ended December 31, 2020, 2019 and 2018, our total revenue was $196.9 million, $181.3 million and $123.2 million, respectively. Manufacturing efficiencies and scale benefits have helped us improve from a gross loss of $11.2 million and $1.6 million for the years ended December 31, 2018 and 2019, to a gross profit of $7.5 million for the year ended December 31, 2020, representing an improvement in gross margin from (9)% and (1)% to 4%. We have also invested significant resources in research and development, operations, and sales and marketing to grow our business and, as a result, generated losses from operations of $96.0 million, $99.7 million and $89.1 million for the years ended December 31, 2020, 2019 and 2018, respectively. Proterra Powered delivered battery systems and electrification solutions for 170 vehicles during 2020, 177 vehicles in 2019, and 135 vehicles in 2018. We have significant manufacturing capacity already in place and at scale with approximately 350,000 square feet of manufacturing space across three facilities in two states. Battery manufacturing capacity at our City of Industry, California facility, once fully staffed, is 675 megawatt-hours (“MWh”), sufficient to supply batteries for both our total bus manufacturing capacity of 680 electric transit buses across our two bus assembly facilities in Greenville, South Carolina and City of Industry, as well as more than 350 MWh of Proterra Powered batteries for OEM customers in other commercial vehicle segments, equivalent to 1,500 school buses and/or delivery vehicles per year.

We have invested heavily in our products and manufacturing capabilities and expect to continue to incur net losses in the short term. We will continue to invest in increasing and optimizing production and expanding our portfolio of products and services. We plan to approach these investments with a view to improving profitability in the long-term, which will allow us to begin reducing our accumulated deficit.

Summary of Risk Factors

In evaluating the proposals to be presented at the ArcLight extraordinary general meeting, a shareholder should carefully read the risks described below, this proxy statement/prospectus and especially consider the factors discussed in the section entitled “Risk Factors.” If any of the following events occur, our business, financial condition and operating results may be materially adversely affected. In that event, the trading price of our securities could decline, and you could lose all or part of your investment. Such risks include, but are not limited to:

Risks related to Proterra’s business

•        Proterra’s limited history of selling battery systems, electrification and charging solutions, fleet and energy management systems, electric transit buses, and related technologies makes it difficult to evaluate Proterra’s business and prospects and may increase the risks associated with your investment.

•        Proterra’s most recent business expansion with Proterra Powered and Proterra Energy may not be as successful as anticipated, may not attract the customers and business partners Proterra expects.

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•        Because many of the markets in which Proterra competes are new and rapidly evolving, it is difficult to forecast long-term end-customer adoption rates and demand for Proterra’s products.

•        Proterra faces intense and increasing competition in the transit bus and commercial vehicle electrification market and may not be able to compete successfully against current and future competitors, which could adversely affect New Proterra’s business, revenue growth, and market share.

•        Proterra has been and may continue to be impacted by macroeconomic conditions resulting from the global COVID-19 pandemic.

•        Proterra’s transit business is significantly dependent on government funding for public transit, and the unavailability, reduction, or elimination of government economic incentives would have an adverse effect on Proterra’s business, prospects, financial condition, and operating results.

•        The growth of Proterra’s transit business is dependent upon the willingness of corporate and other public transportation providers to adopt and fund the purchase of electric vehicles for mass transit.

•        Proterra’s dependence on a limited number of suppliers introduces significant risk that could have adverse effects on Proterra’s financial condition and operating results.

•        Proterra has a long sales, production, and technology development cycle for new public transit customers, which may create fluctuations in whether and when revenue is recognized, and may have an adverse effect on Proterra’s business.

•        Proterra has a history of net losses, anticipate increasing Proterra’s operating expenses in the future, and may not achieve or sustain positive gross margin or profitability in the future.

•        Proterra could incur material losses and costs from product warranty claims, recalls, or remediation of electric transit buses for real or perceived deficiencies or from customer satisfaction campaigns.

•        Increases in costs, disruption of supply, or shortage of materials, particularly lithium-ion cells, could harm Proterra’s business.

•        Proterra’s annual revenue has in the past depended, and will likely continue to depend, on a small number of customers that fluctuate from year to year, and failure to add new customers or expand sales to Proterra’s existing customers could have an adverse effect on New Proterra’s operating results for a particular period.

•        Proterra’s industry and its technology are rapidly evolving and may be subject to unforeseen changes. Developments in alternative technologies and powertrains or improvements in the internal combustion engine may adversely affect the demand for Proterra’s electric transit buses.

•        Proterra may not be able to develop, maintain and grow strategic relationships in the Proterra Powered or Proterra Energy business, identify new strategic relationship opportunities, or form strategic relationships, in the future.

•        Proterra is competing for the business of both small and large transit agencies, which place different demands on Proterra’s business, and if we do not build an organization that can serve both types of transit customers, Proterra’s business may be harmed.

•        Proterra’s business is subject to substantial regulations, which are evolving, and unfavorable changes or failure by us to comply with these regulations could have an adverse effect on Proterra’s business.

•        Proterra’s business could be adversely affected from an accident or safety incident involving Proterra’s battery systems, electrification and charging solutions, fleet and energy management systems, electric transit buses.

•        Proterra may become subject to product liability claims, which could harm Proterra’s financial condition and liquidity if we are not able to successfully defend or insure against such claims.

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•        Changes to U.S. trade policies, including new tariffs or the renegotiation or termination of existing trade agreements or treaties, may adversely affect Proterra’s financial performance.

•        Proterra is subject to various environmental and safety laws and regulations that could impose substantial costs upon Proterra and negatively impact Proterra’s ability to operate Proterra’s manufacturing facilities.

•        Proterra may experience outages and disruptions of Proterra’s services if it fails to maintain adequate security and supporting infrastructure as it scales Proterra’s information technology systems.

•        Proterra may require additional capital to support business growth, and such capital might not be available on terms acceptable to Proterra, if at all.

•        Failure to protect Proterra’s intellectual property could adversely affect Proterra’s business.

•        Proterra may be subject to intellectual property rights claims by third parties, which could be costly to defend, could require Proterra to pay significant damages and could limit Proterra’s ability to use certain technologies.

•        Proterra’s loan and security agreements contain covenants that may restrict Proterra’s business and financing activities.

•        Proterra received a loan under the Paycheck Protection Program of the CARES Act, and all or a portion of the loan may not be forgivable.

•        If Proterra fails to develop and maintain an effective system of disclosure controls and internal control over financial reporting, Proterra’s ability to produce timely and accurate financial statements or comply with applicable law and regulations could be impaired.

•        Regulations related to “conflict minerals” may force Proterra to incur additional expenses, may make Proterra’s supply chain more complex and may result in damage to Proterra’s reputation with customers.

•        Proterra’s management team has limited experience managing a public company.

The Parties to the Business Combination

ArcLight

ArcLight is a blank check company incorporated on July 28, 2020 as a Cayman Islands exempted entity for the purpose of effecting a merger, share exchange, asset acquisition, share purchase, reorganization or similar business combination with one or more businesses or entities, which we refer to throughout this prospectus as our initial business combination. Based on ArcLight’s business activities, it is a “shell company” as defined under the Exchange Act because it has no operations and nominal assets consisting almost entirely of cash.

On September 25, 2020, ArcLight completed its initial public offering of 25,000,000 units, plus an additional 2,750,000 units subsequently issued upon partial exercise of the underwriters’ overallotment option, at a price of $10.00 per unit generating gross proceeds of $277,500,000 before underwriting discounts and expenses. Each unit consisted of one Class A ordinary share and one-half of one public warrant. Each whole public warrant entitles the holder thereof to purchase one Class A ordinary share at an exercise price of $11.50 per share, subject to certain adjustments.

Following the closing of our initial public offering, an amount equal to $277,500,000 of the net proceeds from its initial public offering and the sale of the private placement warrants was placed in the trust account. The trust account may be invested only in U.S. government treasury bills with a maturity of 185 days or less or in money market funds investing solely in United States Treasuries and meeting certain conditions under Rule 2a-7 under the Investment Company Act of 1940, as amended, which invest only in direct U.S. government obligations. As of December 31, 2020, funds in the trust account totaled approximately $277,547,390, all of which were held in U.S. treasury securities. These funds will remain in the trust account, except for the withdrawal of interest to pay taxes, if any, until the earliest of (i) the completion of ArcLight’s initial business combination, (ii) the redemption of any public shares properly tendered in connection with a shareholder vote to amend the Existing Governing Documents to modify the substance and timing of our obligation to redeem 100% of the public shares if ArcLight

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does not complete a business combination by September 25, 2022, or (iii) the redemption of all of the public shares if ArcLight is unable to complete a business combination by September 25, 2022 (unless such date is extended in accordance with the Existing Governing Documents), subject to applicable law.

ArcLight’s units, public shares and public warrants are currently listed on Nasdaq under the symbols “ACTCU,” “ACTC” and “ACTCW,” respectively.

ArcLight’s principal executive office is located at 200 Clarendon Street, 55th Floor, Boston, Massachusetts, 02116, and its telephone number is (617) 531-6300. ArcLight’s corporate website address is https://www.arclightclean.com/. ArcLight’s website and the information contained on, or that can be accessed through, the website is not deemed to be incorporated by reference in, and is not considered part of, this proxy statement/prospectus.

Proterra

Proterra was formed in June 2004 as Mobile Energy Solutions, LLC, a Colorado limited liability company. In February 2010, Proterra became a Delaware corporation and changed its name to Proterra Inc.

Proterra’s principal executive office is located at 1815 Rollins Road, Burlingame, California 94010, and its telephone number is (864) 438-0000. Proterra’s corporate website address is https://www.proterra.com/. Proterra’s website and the information contained on, or that can be accessed through, the website is not deemed to be incorporated by reference in, and is not considered part of, this proxy statement/prospectus.

Phoenix Merger Sub

Phoenix Merger Sub is a Delaware corporation and wholly-owned subsidiary of ArcLight formed for the purpose of effecting the Business Combination. Phoenix Merger Sub owns no material assets and does not operate any business.

Phoenix Merger Sub’s principal executive office is located at 200 Clarendon Street, 55th Floor, Boston, Massachusetts, 02116, and its telephone number is (617) 531-6300.

Proposals to be put to the Shareholders of ArcLight at the Extraordinary General Meeting

The following is a summary of the proposals to be put to the extraordinary general meeting of ArcLight and certain transactions contemplated by the Merger Agreement. Each of the proposals below, except the Adjournment Proposal, is cross-conditioned on the approval of each other. The Adjournment Proposal is not conditioned upon the approval of any other proposal set forth in this proxy statement/prospectus. The transactions contemplated by the Merger Agreement will be consummated only if the Condition Precedent Proposals are approved at the extraordinary general meeting.

As discussed in this proxy statement/prospectus, ArcLight is asking its shareholders to approve by ordinary resolution the Merger Agreement, pursuant to which, among other things, on the Closing Date, promptly following the consummation of the Domestication, Phoenix Merger Sub will merge with and into Proterra, with Proterra as the surviving company in the Merger and, after giving effect to such Merger, Proterra shall be a wholly-owned subsidiary of ArcLight. In accordance with the terms and subject to the conditions of the Merger Agreement, at the Effective Time, (i) each share of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for 0.8925 shares of New Proterra Common Stock, (ii) each warrant and equity award of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for comparable warrants or equity awards that are exercisable for 0.8925 shares of New Proterra Common Stock, as applicable, and (iii) each Convertible Note that is not optionally converted immediately prior to the Effective Time will become convertible into shares of New Proterra Common Stock, in accordance with the terms of the Convertible Notes. For further details, see “Business Combination Proposal — Consideration to Proterra Holders in the Business Combination.

After consideration of the factors identified and discussed in the section entitled “Business Combination Proposal — The ArcLight Board’s Reasons for the Business Combination,” the ArcLight Board concluded that the Business Combination met all of the requirements disclosed in the prospectus for ArcLight’s initial public offering, including that the businesses of Proterra had a fair market value of at least 80% of the balance of the funds in the trust account at the time of execution of the Merger Agreement. For more information about the transactions contemplated by the Merger Agreement, see “Business Combination Proposal.”

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Consideration to Proterra Holders in the Business Combination

In accordance with the terms and subject to the conditions of the Merger Agreement, at the Effective Time, (i) each share of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for 0.8925 shares of New Proterra Common Stock, (ii) each warrant and equity award of Proterra outstanding as of immediately prior to the Effective Time will be exchanged for comparable warrants or equity awards that are exercisable for 0.8925 shares of New Proterra Common Stock, as applicable, and (iii) each Convertible Note that is not optionally converted immediately prior to the Effective Time will become convertible into shares of New Proterra Common Stock, in accordance with the terms of the Convertible Notes. For further details, see “Business Combination Proposal — Consideration to Proterra Holders in the Business Combination.”

Conditions to Closing of the Business Combination

The consummation of the Business Combination is conditioned upon, among other things, (i) the approval by our shareholders of the Condition Precedent Proposals being obtained; (ii) the applicable waiting period under the HSR Act relating to the Merger Agreement having expired or been terminated; (iii) the Aggregate Transaction Proceeds Condition; (iv) the approval by Nasdaq of our initial listing application in connection with the Business Combination; and (v) the consummation of the Domestication. Therefore, unless these conditions are waived by the applicable parties to the Merger Agreement, the Merger Agreement could terminate and the Business Combination may not be consummated. For further details, see “Business Combination Proposal — Conditions to Closing of the Business Combination.”

Domestication Proposal

As discussed in this proxy statement/prospectus, ArcLight will ask its shareholders to approve by special resolution the Domestication Proposal. As a condition to closing the Business Combination pursuant to the terms of the Merger Agreement, the ArcLight Board has unanimously approved the Domestication Proposal. The Domestication Proposal, if approved, will authorize a change of ArcLight’s jurisdiction of incorporation from the Cayman Islands to the State of Delaware. Accordingly, while ArcLight is currently incorporated as an exempted company under the Cayman Islands Companies Law, upon Domestication, New Proterra will be governed by the DGCL. There are differences between Cayman Islands corporate law and Delaware corporate law as well as the Existing Governing Documents and the Proposed Governing Documents. The approval of the Domestication Proposal requires a special resolution under Cayman Islands law, being the affirmative vote of holders at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter. Accordingly, we encourage shareholders to carefully consult the information set out below under “Comparison of Corporate Governance and Shareholder Rights.”

For further details, see “Domestication Proposal” and “Governing Documents Proposals.”

Governing Documents Proposals

ArcLight will ask its shareholders to approve by ordinary resolution (unless otherwise stated) four (4) separate Governing Documents Proposals in connection with the replacement of the Existing Governing Documents, under Cayman Islands law, with the Proposed Governing Documents, under the DGCL. The ArcLight Board has unanimously approved each of the Governing Documents Proposals and believes such proposals are necessary to adequately address the needs of New Proterra after the Business Combination. Approval of each of the Governing Documents Proposals is a condition to the consummation of the Business Combination. A brief summary of each of the Governing Documents Proposals is set forth below. These summaries are qualified in their entirety by reference to the complete text of the Proposed Governing Documents.

•        Governing Documents Proposal A — to authorize the change in the authorized share capital of ArcLight from US$55,500 divided into (i) 500,000,000 Class A ordinary shares, par value $0.0001 per share, 50,000,000 Class B ordinary shares, par value $0.0001 per share, and 5,000,000 preference shares, par value $0.0001 per share, to (ii) 500,000,000 shares of New Proterra Common Stock and 10,000,000 shares of New Proterra Preferred Stock.

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•        Governing Documents Proposal B — to authorize the New Proterra Board to issue any or all shares of New Proterra Preferred Stock in one or more classes or series, with such terms and conditions as may be expressly determined by the New Proterra Board and as may be permitted by the DGCL.

•        Governing Documents Proposal C — to authorize the removal of the ability of New Proterra stockholders to take action by written consent in lieu of a meeting.

•        Governing Documents Proposal D — as a special resolution, to amend and restate the Existing Governing Documents and authorize all other changes necessary or, as mutually agreed in good faith by ArcLight and Proterra, desirable in connection with the replacement of Existing Governing Documents with the Proposed Governing Documents as part of the Domestication, including (i) making New Proterra’s corporate existence perpetual, (ii) adopting Delaware as the exclusive forum for certain stockholder litigation, provided, that the exclusive forum provision in our restated certificate of incorporation does not apply to claims arising out of the Securities Act of 1933, as amended, and the Securities Exchange Act of 1934, as amended, for which the federal district courts of the United States are the exclusive forum, (iii) electing to not be governed by Section 203 of the DGCL and limiting certain corporate takeovers by interested stockholders and (iv) removing certain provisions related to our status as a blank check company that will no longer be applicable upon consummation of the Business Combination, all of which the ArcLight Board believes is necessary to adequately address the needs of New Proterra after the Business Combination.

The Proposed Governing Documents differ in certain material respects from the Existing Governing Documents, and we encourage shareholders to carefully consult the information set out in the section entitled “Governing Documents Proposals” and the full text of the Proposed Governing Documents of New Proterra, attached hereto as Annexes C and D.

Nasdaq Proposal

Our shareholders are also being asked to approve, by ordinary resolution, the Nasdaq Proposal. Our units, public shares and public warrants are listed on Nasdaq and, as such, we are seeking shareholder approval for issuance of New Proterra Common Stock in connection with the Business Combination and the PIPE Financing pursuant to Nasdaq Listing Rule 5635.

For additional information, see “Nasdaq Proposal.”

Equity Incentive Plan Proposal

Our shareholders are also being asked to approve, by ordinary resolution, the Equity Incentive Plan Proposal. Pursuant to the Equity Incentive Plan, a number of shares of New Proterra Common Stock equal to 10,000,000 shares of New Proterra Common Stock that are outstanding on an as-converted and as-redeemed basis as of the date immediately following the consummation of the Business Combination will be reserved for issuance under the Incentive Award Plan. The Equity Incentive Plan provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1, beginning on January 1, 2022, and continuing through January 1, 2031, by 4.0% of the outstanding number of shares of New Proterra Common Stock on the immediately preceding December 31, or such lesser amount as determined by the Board of New Proterra. For additional information, see “Equity Incentive Plan Proposal.” The full text of the Incentive Award Plan is attached hereto as Annex H.

Employee Stock Purchase Plan Proposal

Our shareholders are also being asked to approve, by ordinary resolution, the Employee Stock Purchase Plan Proposal. A total of 1,630,000 shares of New Proterra Common Stock will be reserved for issuance under the ESPP. Based upon a price per share of $10.00, the maximum aggregate market value of the New Proterra Common Stock that could potentially be issued under the ESPP at Closing is $16,300,000. The ESPP provides that the number of shares reserved and available for issuance under the ESPP will automatically increase each January 1, beginning on January 1, 2022, and continuing through January 1, 2031, by 1.0% of the outstanding number of shares of New Proterra Common Stock on the immediately preceding December 31, or such lesser amount as determined by the New Proterra Board. For additional information, see “Employee Stock Purchase Plan Proposal.” The full text of the ESPP is attached hereto as Annex I.

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Adjournment Proposal

If, based on the tabulated vote, there are not sufficient votes at the time of the extraordinary general meeting to authorize ArcLight to consummate the Business Combination, the ArcLight Board may submit a proposal to adjourn the extraordinary general meeting to a later date or dates to consider and vote upon a proposal to approve by ordinary resolution the adjournment of the extraordinary general meeting to a later date or dates. For additional information, see “Adjournment Proposal.”

The Adjournment Proposal is not conditioned on any other proposal.

The ArcLight Board’s Reasons for the Business Combination

ArcLight was formed for the purpose of effecting a merger, capital stock exchange, asset acquisition, share purchase, reorganization or similar business combination with one or more businesses. The ArcLight Board sought to do this by utilizing the networks and industry experience of both the Sponsor and the ArcLight Board and management to identify, acquire and operate one or more businesses. The members of the ArcLight Board and management have extensive transactional experience, particularly in the energy infrastructure industry.

As described under “The Background of the Merger,” the ArcLight Board, in evaluating the Merger, consulted with ArcLight’s management and legal advisors. In reaching its unanimous decision to approve the Merger Agreement and the transactions contemplated by the Merger Agreement, the ArcLight Board considered a range of factors, including, but not limited to, the factors discussed below. In light of the number and wide variety of factors considered in connection with its evaluation of the proposed combination, the ArcLight Board did not consider it practicable to, and did not attempt to, quantify or otherwise assign relative weights to the specific factors that it considered in reaching its determination and supporting its decision. The ArcLight Board contemplated its decision as in the context of all of the information available and the factors presented to and considered by it. In addition, individual directors may have given different weight to different factors. This explanation of ArcLight’s reasons for approving the combination and all other information presented in this section is forward-looking in nature and, therefore, should be read in light of the factors discussed under the section titled “Cautionary Note Regarding Forward-Looking Statements.

In approving the combination, the ArcLight Board decided not to obtain a fairness opinion. The officers and directors of ArcLight have substantial experience in evaluating the operating and financial merits of companies from a wide range of industries and concluded that their experience and background, together with the experience of their representatives, enabled them to make the necessary analyses and determinations regarding the Merger.

The ArcLight Board considered a number of factors pertaining to the Merger as generally supporting its decision to enter into the Merger Agreement and the transactions contemplated thereby, including, but not limited to, the following: Proterra’s strategic focus on and demonstrable contributions toward global sustainability and decarbonization, the quality of its products, the experience of the management team, the successful history of scaling manufacturing, the prudent financial management of the business, the proven ability to improve the economics of the business over time, and more generally the large market opportunity across electric vehicles, electric powertrains and charging infrastructure (where Proterra was already a proven leader working with strong partners and customers). The ArcLight Board and management team alike were impressed with the Proterra team during the diligence process and in their own investigation of the broader electric vehicle industry. More specifically, the ArcLight Board took into consideration the following factors or made the following determinations, as applicable:

•        Meets the acquisition criteria that ArcLight had established to evaluate prospective business combination targets;

•        Leadership in electric vehicles, electric powertrains, and charging product development and commercialization;

•        Strong uptake of Proterra’s products;

•        Unique exposure to attractive tailwinds in a growing electric vehicle market;

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•        Multiple avenues to accelerate organic growth opportunities;

•        Significant value creation opportunities;

•        Experienced management team;

•        Strong commitment of existing Proterra stockholders;

•        Proterra’s post-closing financial condition; and

•        Valuation supported by financial analysis and due diligence.

The ArcLight Board also considered a variety of uncertainties, risks and other potentially negative factors relating to the Merger including, but not limited to, the following: redemptions, complexities related to the shareholder vote, litigation and threats of litigation and broader macro risks, including the potential for limited state and local procurement budgets for Proterra’s transit vehicles, battery design roadmap and associated cost competitiveness over the long-term and potential safety malfunctions with its products. Specifically, the ArcLight Board considered the following issues and risks:

•        Risk that the benefits described above may not be achieved;

•        Risk of the liquidation of ArcLight;

•        Exclusivity;

•        Risk regarding the shareholder vote;

•        Limitations of review;

•        Closing conditions;

•        Potential litigation;

•        Fees and expenses; 

•        Potential impacts of COVID-19; and

•        Other risk factors.

In addition to considering the factors described above, the ArcLight Board also considered that some officers and directors of ArcLight might have interests in the Merger as individuals that are in addition to, and that may be different from, the interests of ArcLight’s stockholders. ArcLight’s independent directors reviewed and considered these interests during the negotiation of the Merger and in evaluating and unanimously approving, as members of the ArcLight Board, the Merger Agreement and the transactions contemplated thereby, including the Merger.

The ArcLight Board concluded that the potential benefits that it expected ArcLight and its stockholders to achieve as a result of the Merger outweighed the potentially negative factors associated with the Merger. Accordingly, the ArcLight Board unanimously determined that the Merger Agreement, and the transactions contemplated thereby, including the Merger, were advisable, fair to, and in the best interests of, ArcLight and its stockholders.

For more information about the ArcLight Board’s decision-making process concerning the Business Combination, please see the section entitled “The Business Combination Proposal — the ArcLight Board’s Reasons for the Business Combination.”

Related Agreements

This section describes certain additional agreements entered into or to be entered into in connection with the Merger Agreement.

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PIPE Financing

ArcLight entered into Subscription Agreements (the “Subscription Agreements”) with the PIPE Investors to consummate the PIPE Financing, pursuant to which the PIPE Investors have agreed to subscribe for and purchase, and ArcLight has agreed to issue and sell to the PIPE Investors, an aggregate of 41,500,000 shares of New Proterra Common Stock at a price of $10.00 per share, for aggregate gross proceeds of $415,000,000. The New Proterra Common Stock to be issued pursuant to the Subscription Agreements have not been registered under the Securities Act in reliance upon the exemption provided in Section 4(a)(2) of the Securities Act. ArcLight has granted the PIPE Investors certain registration rights in connection with the PIPE Financing. The PIPE Financing is contingent upon, among other things, the substantially concurrent closing of the Business Combination.

As part of the 41,500,000 shares of New Proterra Common Stock to be issued pursuant to the Subscription Agreements, certain affiliates of ArcLight have agreed to subscribe for and purchase 600,000 shares of New Proterra Common Stock on the same terms and conditions of the other PIPE Investors at a price of $10.00 per share, for aggregate gross proceeds of $6,000,000.

Sponsor Support Agreement

Concurrently with the execution of the Merger Agreement, the Initial Shareholders entered into a Sponsor Support Agreement (the “Sponsor Support Agreement”) with ArcLight and Proterra, pursuant to which the Initial Shareholders agreed to, among other things, (i) vote at any meeting of the shareholders of ArcLight all of their ordinary shares held of record or thereafter acquired in favor of the proposals being presented at the extraordinary general meeting of ArcLight, (ii) be bound by certain other covenants and agreements related to the Business Combination and (iii) be bound by certain transfer restrictions with respect to such securities, prior to the closing of the Business Combination, in each case, on the terms and subject to the conditions set forth in the Sponsor Support Agreement. For additional information, see “Business Combination Proposal — Related Agreements — Sponsor Support Agreement.”

Sponsor Letter Agreement

Concurrently with the execution of the Merger Agreement, the Sponsor entered into the Sponsor Letter Agreement (as amended, the “Sponsor Letter Agreement”) with ArcLight and Proterra, pursuant to which the parties thereto agreed, among other things, (i) to certain vesting and forfeiture terms with respect to 10% of the New Proterra Common Stock beneficially owned by the Sponsor immediately following the closing, (ii) to cause ArcLight’s designee to the ArcLight Board to resign in the event the Sponsor sells, disposes of, transfers or assigns (other than to an affiliate) 50% or more of the ordinary shares held beneficially by the Sponsor as of the closing of the Business Combination, and (iii) to subject the Sponsor to a 180-day post-closing lock-up with respect to its shares of New Proterra Common Stock, in each case, on the terms and subject to the conditions set forth in the Sponsor Letter Agreement. The Sponsor Letter Agreement was subsequently amended (the “Early Release Amendment”) to provide that the 180 day post-closing lock-up period will terminate early with respect to (A) 33% of the shares subject to the lock-up agreement on the business day after the Release Condition (as defined below) is satisfied during the period starting on the day after the Closing Date and ending on the 119th day after the Closing Date; provided, that such early termination will occur no earlier than the later of sixty (60) days after the Closing and thirty (30) days after the registration statement registering shares of New Proterra Common Stock issued in the PIPE Financing is declared effective under the Securities Act; and (B) 33% of the shares subject to the lock-up agreement on the business day after the Release Condition is satisfied during the period starting 120 days after the Closing. The “Release Condition” occurs if over any 20 trading days within any 30 trading day period, the VWAP of the New Proterra Common Stock is greater than or equal to $20.00 per share or there occurs any transaction resulting in a change in control with a valuation of the New Proterra Common Stock that is greater than or equal to $20.00 per share.

Proterra Stockholder Support Agreements

Concurrently with the execution of the Merger Agreement, certain stockholders of Proterra representing the requisite votes necessary to approve the Business Combination entered into support agreements (the “Proterra Stockholder Support Agreements”) with ArcLight and Proterra, pursuant to which each such holder agreed to (i) vote at any meeting of the shareholders of Proterra all of its Proterra Common Stock held of record or thereafter

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acquired in favor of the proposals being presented at the extraordinary general meeting of ArcLight and appoint ArcLight as such holder’s proxy, (ii) be bound by certain other covenants and agreements related to the Business Combination and (iii) be bound by certain transfer restrictions with respect to such securities, in each case, on the terms and subject to the conditions set forth in Proterra Stockholder Support Agreements.

Amended and Restated Registration Rights Agreement

At the Closing, New Proterra, the Sponsor and other holders of New Proterra Common Stock will enter into an Amended and Restated Registration Rights Agreement (the “Amended and Restated Registration Rights Agreement”), which will supersede the registration and shareholder rights agreement between ArcLight and its initial shareholders, pursuant to which, among other things, the Sponsor and such holders will be granted certain customary registration rights, demand rights and piggyback rights with respect to their respective shares of New Proterra Common Stock. For additional information, see “Business Combination Proposal — Related Agreements — Amended and Restated Registration Rights Agreement.”

Ninth Amended and Restated Investors’ Rights Agreement

Concurrently with the execution of the Merger Agreement, Proterra and certain holders of its convertible preferred stock including entities affiliated with certain of Proterra’s directors and holders of more than 5% Proterra’s outstanding capital stock, entered into the Ninth Amended and Restated Investors’ Rights Agreement (the “IRA”). Pursuant to the IRA, certain of Proterra’s stockholders are entitled to certain information rights, rights to participate in certain additional issuances of Proterra’s capital stock and rights with respect to the registration of their shares. Further, the parties to the IRA agreed to be subject to a post-closing lock-up with respect to their common shares for a period of 180 days, subject to customary terms; provided that any waiver, termination, shortening or other modification to similar restrictions applicable to such shares shall apply pro rata. The lock-up release provisions set forth in the Early Release Amendment will also apply to the parties to the IRA. All of the terms of the IRA, except for the lock-up provisions, will terminate in connection with the Closing.

Amendment No. 1 to the Ninth Amended and Restated Voting Agreement

Concurrently with the execution of the Merger Agreement, Proterra and certain holders of its convertible preferred stock including entities affiliated with certain of Proterra’s directors and holders of more than 5% Proterra’s outstanding capital stock, entered into the Amendment No. 1 to Ninth Amended and Restated Voting Agreement, dated August 2, 2019, pursuant to which such parties have agreed that the Proterra stockholders party to that agreement may enter into certain support agreements, including the Transaction Support Agreements, and that upon the Closing, the voting agreement, as amended, will terminate automatically.

Amendment No. 1 to the Eighth Amended and Restated Right of First Refusal and Co-Sale Agreement

Concurrently with the execution of the Merger Agreement, Proterra and certain holders of its convertible preferred stock including entities affiliated with certain of Proterra’s directors and holders of more than 5% Proterra’s outstanding capital stock, entered into the Amendment No. 1 to Eighth Amended and Restated Right of First Refusal and Co-Sale Agreement, dated August 2, 2019, pursuant to which such parties have agreed that upon the Closing, the right of first refusal and co-sale agreement, as amended, will terminate automatically.

Ownership of New Proterra

As of the date of this proxy statement/prospectus, there are 34,687,500 ordinary shares issued and outstanding, which includes an aggregate of 6,937,500 Class B ordinary shares held by the Initial Shareholders, including the Sponsor. In addition, as of the date of this proxy statement/prospectus, there is outstanding an aggregate of 21,425,000 warrants to acquire ordinary shares, comprised of 7,550,000 private placement warrants held by the Sponsor and 13,875,000 public warrants. Each whole warrant entitles the holder thereof to purchase one Class A ordinary share and, following the Domestication, will entitle the holder thereof to purchase one share of New Proterra Common Stock. Therefore, as of the date of this proxy statement/prospectus (without giving effect to the Business Combination and assuming that none of ArcLight’s outstanding public shares are redeemed in connection with the Business Combination), ArcLight’s fully diluted share capital would be 56,112,500 ordinary shares.

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The following table illustrates varying ownership levels in New Proterra Common Stock immediately following the consummation of the Business Combination based on the varying levels of redemptions by the public shareholders and the following additional assumptions: (i) 164,863,846 shares of New Proterra Common Stock are issued to the Proterra Holders at Closing in a no redemption scenario and 167,512,081 shares of New Proterra Common Stock are issued to the Proterra Holders at Closing in a maximum redemption scenario; (ii) 41,500,000 shares of New Proterra Common Stock are issued in the PIPE Financing; and (iii) no ArcLight warrants to purchase New Proterra Common Stock that will be outstanding immediately following Closing have been exercised. The share totals in clause (i) of the prior sentence are calculated assuming that all outstanding warrants and vested, in-the-money equity awards are net exercised using a $10.00 per share value, based on vesting as of February 28, 2021, assuming the conversion of the principal balance of the Convertible Notes, and without taking into account the effect of accrued unpaid cash interest or paid-in-kind interest. See “Unaudited Pro Forma Condensed Combined Financial Information” for more details. If the actual facts differ from these assumptions, the ownership percentages in ArcLight will be different and totals may not add up to 100% due to rounding.

 

Share Ownership in
New Proterra
(Percentage of Outstanding Shares)

   

No
redemptions

 

Maximum redemptions

Proterra Holders(1)

 

68.6

%

 

77.8

%

PIPE Investors(2)

 

17.3

%

 

19.3

%

ArcLight public shareholders(3)

 

11.5

%

 

0.0

%

Initial Shareholders(4)

 

2.6

%

 

2.9

%

____________

(1)      Assumes that the number of shares of New Proterra Common Stock to be held by Proterra Holders is 164,863,846 shares in the no redemption scenario and 167,512,081 in the maximum redemption scenario. The shares to be issued for outstanding warrants, vested stock options and Convertible Notes are calculated on a cashless exercise basis, based on a deemed value of $10.00 per share, and as if converted at the Closing, and excludes the effect of accrued interest on the Convertible Notes. See “Unaudited Pro Forma Condensed Combined Financial Information” for more details. The number of vested options is calculated as of February 28, 2021.

(2)      Consists of 41,500,000 shares to be acquired in connection with the PIPE Financing, including 600,000 shares to be acquired by certain affiliates of ArcLight.

(3)      Includes (i) 25,000,000 shares issued in connection with ArcLight’s initial public offering and (ii) an additional 2,750,000 shares issued pursuant to the partial exercise by the underwriters of their over-allotment option in connection with ArcLight’s initial public offering.

(4)      Includes 6,257,750 shares of New Proterra Common Stock. Does not include 679,750 shares of New Proterra Common Stock received by the Sponsor at Closing, which are subject to forfeiture upon the failure to achieve certain price targets following the consummation of the Business Combination. Does not include 600,000 shares to be acquired by certain affiliates of ArcLight in the PIPE Financing.

For further details, see “Business Combination Proposal — Consideration to Proterra Holders in the Business Combination.”

Date, Time and Place of Extraordinary General Meeting of ArcLight’s Shareholders

The extraordinary general meeting will be held at             ,           Time, on           , 2021 at the offices of Kirkland & Ellis LLP located at             , unless the extraordinary general meeting is adjourned., to consider and vote upon the proposals to be put to the extraordinary general meeting, including if necessary, the Adjournment Proposal, to permit further solicitation and vote of proxies if, based upon the tabulated vote at the time of the extraordinary general meeting, each of the Condition Precedent Proposals have not been approved.

Voting Power; Record Date

ArcLight shareholders will be entitled to vote or direct votes to be cast at the extraordinary general meeting if they owned ordinary shares at the close of business on             , 2021, which is the “record date” for the extraordinary general meeting. Shareholders will have one vote for each ordinary share owned at the close of business on the record date. If your shares are held in “street name” or are in a margin or similar account, you

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should contact your broker to ensure that votes related to the shares you beneficially own are properly counted. Our warrants do not have voting rights. As of the close of business on the record date, there were 34,687,500 ordinary shares issued and outstanding, of which 27,750,000 were issued and outstanding public shares.

Quorum and Vote of ArcLight Shareholders

A quorum of ArcLight shareholders is necessary to hold a valid meeting. A quorum will be present at the extraordinary general meeting if one or more shareholders who together hold not less than a majority of the issued and outstanding ordinary shares entitled to vote at the extraordinary general meeting are represented in person or by proxy at the extraordinary general meeting. As of the record date for the extraordinary general meeting, 17,343,751 ordinary shares would be required to achieve a quorum.

The Initial Shareholders have, pursuant to the Sponsor Support Agreement, agreed to, among other things, vote all of their ordinary shares in favor of the proposals being presented at the extraordinary general meeting. As of the date of this proxy statement/prospectus, the Initial Shareholders own 20.0% of the issued and outstanding ordinary shares. See “Business Combination Proposal — Related Agreements — Sponsor Letter Agreement” in the accompanying proxy statement/prospectus for more information related to the Sponsor Letter Agreement.

The proposals presented at the extraordinary general meeting require the following votes:

(i)     Business Combination Proposal:    The approval of the Business Combination Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(ii)    Domestication Proposal:    The approval of the Domestication Proposal requires a special resolution under Cayman Islands law, being the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(iii)   Governing Documents Proposals:    The separate approval of each of the Governing Documents Proposals requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter, other than Proposal D which requires a special resolution under Cayman Islands law, being the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(iv)   Nasdaq Proposal:    The approval of the Nasdaq Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(v)    Equity Incentive Plan Proposal:    The approval of the Equity Incentive Plan Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

(vi)   Employee Stock Purchase Plan Proposal:    The approval of the Employee Stock Purchase Plan Proposal requires an ordinary resolution, being the affirmative vote of a majority of the ordinary shares represented in person or by proxy and entitled to vote thereon and who vote at the extraordinary general meeting.

(vii)  Adjournment Proposal:    The approval of the Adjournment Proposal requires an ordinary resolution, being the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter.

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Redemption Rights

Pursuant to the Existing Governing Documents, a public shareholder may request that ArcLight redeem all or a portion of its public shares for cash if the Business Combination is consummated. As a holder of public shares, you will be entitled to receive cash for any public shares to be redeemed only if you:

(i)     (a) hold public shares or (b) if you hold public shares through units, you elect to separate your units into the underlying public shares and warrants prior to exercising your redemption rights with respect to the public shares;

(ii)    submit a written request to Continental, ArcLight’s transfer agent, in which you (i) request that ArcLight redeem all or a portion of your public shares for cash, and (ii) identify yourself as the beneficial holder of the public shares and provide your legal name, phone number and address; and

(iii)   deliver your public shares to Continental, ArcLight’s transfer agent, physically or electronically through DTC.

Holders must complete the procedures for electing to redeem their public shares in the manner described above prior to ,             Time, on             , 2021 (two business days before the extraordinary general meeting) in order for their shares to be redeemed.

Holders of units must elect to separate the units into the underlying public shares and public warrants prior to exercising redemption rights with respect to the public shares. Public holders that hold their units in an account at a brokerage firm or bank, must notify their broker or bank that they elect to separate the units into the underlying public shares and public warrants, or if a holder holds units registered in its own name, the holder must contact Continental, ArcLight’s transfer agent, directly and instruct them to do so. The redemption rights include the requirement that a holder must identify itself in writing as a beneficial holder and provide its legal name, phone number and address to Continental in order to validly redeem its shares. Public shareholders may elect to redeem all or a portion of the public shares held by them regardless of if or how they vote in respect of the Business Combination Proposal. If the Business Combination is not consummated, the public shares will be returned to the respective holder, broker or bank. If the Business Combination is consummated, and if a public shareholder properly exercises its right to redeem all or a portion of the public shares that it holds and timely delivers its shares to Continental, ArcLight’s transfer agent, New Proterra will redeem such public shares for a per-share price, payable in cash, equal to the pro rata portion of the trust account, calculated as of two business days prior to the consummation of the Business Combination. For illustrative purposes, this would have amounted to approximately $10.56 per issued and outstanding public share, based on 26,290,616 shares subject to possible redemption as of December 31, 2020. If a public shareholder exercises its redemption rights in full, then it will be electing to exchange its public shares for cash and will no longer own public shares. The redemption takes place following the Domestication and accordingly it is shares of New Proterra Common Stock that will be redeemed immediately after consummation of the Business Combination. See “Extraordinary General Meeting of ArcLight — Redemption Rights” in this proxy statement/prospectus for a detailed description of the procedures to be followed if you wish to redeem your public shares for cash.

Notwithstanding the foregoing, a public shareholder, together with any affiliate of such public shareholder or any other person with whom such public shareholder is acting in concert or as a “group” (as defined in Section 13(d)(3) of the Exchange Act), will be restricted from redeeming its public shares with respect to more than an aggregate of 15% of the public shares. Accordingly, if a public shareholder, alone or acting in concert or as a group, seeks to redeem more than 15% of the public shares, then any such shares in excess of that 15% limit would not be redeemed for cash.

The Initial Shareholders have, pursuant to the Sponsor Support Agreement, agreed to, among other things, vote all of their ordinary shares in favor of the proposals being presented at the extraordinary general meeting and waive their anti-dilution rights with respect to their Class B ordinary shares in connection with the consummation of the Business Combination. Such shares will be excluded from the pro rata calculation used to determine the per-share redemption price. As of the date of this proxy statement/prospectus, the Initial Shareholders own 20.0% of the issued and outstanding ordinary shares. See “Business Combination Proposal — Related Agreements — Sponsor Letter Agreement” in the accompanying proxy statement/prospectus for more information related to the Sponsor Letter Agreement.

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Holders of the warrants will not have redemption rights with respect to the warrants.

Appraisal Rights

Neither ArcLight shareholders nor ArcLight warrant holders have appraisal rights in connection with the Business Combination or the Domestication under the Cayman Islands Companies Law or under the DGCL.

Proxy Solicitation

Proxies may be solicited by mail, telephone or in person. ArcLight has engaged Morrow to assist in the solicitation of proxies.

If a shareholder grants a proxy, it may still vote its shares in person if it revokes its proxy before the extraordinary general meeting. A shareholder also may change its vote by submitting a later-dated proxy as described in the section entitled “Extraordinary General Meeting of ArcLight — Revoking Your Proxy.”

Interests of ArcLight’s Directors and Executive Officers in the Business Combination

When you consider the recommendation of the ArcLight Board in favor of approval of the Business Combination Proposal, you should keep in mind that the Initial Shareholders, including ArcLight’s directors, may have interests in such proposal that are different from, or in addition to, those of ArcLight shareholders and warrant holders generally. These interests include, among other things, the interests listed below:

•        the fact that our Initial Shareholders have agreed not to redeem any ordinary shares held by them in connection with a shareholder vote to approve a proposed initial business combination;

•        the fact that the Sponsor paid an aggregate of $25,000 for 8,625,000 Class B ordinary shares, 6,937,500 of which are currently owned by the Initial Shareholders. The 6,937,500 shares of New Proterra Common Stock that the Initial Shareholders will hold following the Business Combination, if unrestricted and freely tradable, and in the case of the shares held by the Sponsor, assuming all vesting conditions are satisfied, would have had an aggregate market value of $124,875,000 based upon the closing price of $18.00 per public share on the Nasdaq on April 6, 2021, the most recent closing price;

•        the fact that the Initial Shareholders and certain of ArcLight’s current officers have agreed to waive their rights to liquidating distributions from the trust account with respect to any ordinary shares (other than public shares) held by them if ArcLight fails to complete an initial business combination by September 25, 2022;

•        the fact that Sponsor paid $7,550,000 for 7,550,000 private placement warrants, which, if unrestricted and freely tradable, would have had an aggregate market value of $48,320,000 based upon the closing price of $6.40 per public warrant (although holders of the private placement warrants have certain rights that differ from the rights of holders of the public warrants) on Nasdaq on April 6, 2021, the most recent closing price, and the fact that the private placement warrants will expire worthless if a business combination is not consummated by September 25, 2022 (unless such date is extended in accordance with the Existing Governing Documents);

•        the fact that certain officers and Sponsor-affiliated directors of ArcLight are investors in ArcLight CTC Investors, which has agreed to subscribe for and purchase 600,000 shares of New Proterra Common Stock at $10.00 per share in the PIPE Financing on the same terms and conditions as the other PIPE Investors, for aggregate gross proceeds of $6,000,000. Such shares of New Proterra Common Stock would have had an estimated aggregate value of $10,800,000 based on the closing price of $18.00 per public share on Nasdaq on April 6, 2021, the most recent closing price;

•        the fact that the Amended and Restated Registration Rights Agreement will be entered into by the Sponsor and certain other affiliates of ArcLight;

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•        the fact that, at the option of the Sponsor, and with the consent of Proterra, any amounts outstanding under any loan made by the Sponsor or any of its affiliates to ArcLight in an aggregate amount of up to $1,500,000 may be converted into warrants to purchase Class A ordinary shares in connection with the consummation of the Business Combination;

•        the continued indemnification of ArcLight’s directors and officers and the continuation of ArcLight’s directors’ and officers’ liability insurance after the Business Combination (i.e., a “tail policy”);

•        the fact that the Sponsor and ArcLight’s officers and directors will lose their entire investment in ArcLight and will not be reimbursed for any out-of-pocket expenses if an initial business combination is not consummated by September 25, 2022;

•        the fact that if the trust account is liquidated, including in the event ArcLight is unable to complete an initial business combination by September 25, 2022, the Sponsor has agreed to indemnify ArcLight to ensure that the proceeds in the trust account are not reduced below $10.00 per public share, or such lesser per public share amount as is in the trust account on the liquidation date, by the claims of prospective target businesses with which ArcLight has entered into an acquisition agreement or claims of any third party for services rendered or products sold to ArcLight, but only if such a vendor or target business has not executed a waiver of any and all rights to seek access to the trust account;

•        the fact that ArcLight may be entitled to distribute or pay over funds held by ArcLight outside the Trust Account to the Sponsor or any of its Affiliates prior to the Closing; and

•        the fact that the Initial Shareholders entered into the Sponsor Support Agreement pursuant to which the original lock-up period to which our Sponsor and our directors and executive officers are subject was amended to remove such lock-up period, but only with respect to securities that are not held by the Sponsor.

The Initial Shareholders have, pursuant to the Sponsor Support Agreement, agreed to, among other things, vote all of their ordinary shares in favor of the proposals being presented at the extraordinary general meeting and waive their anti-dilution rights with respect to their Class B ordinary shares in connection with the consummation of the Business Combination. Such shares will be excluded from the pro rata calculation used to determine the per-share redemption price. As of the date of this proxy statement/prospectus, the Initial Shareholders own 20.0% of the issued and outstanding ordinary shares. See “Business Combination Proposal — Related Agreements — Sponsor Letter Agreement” in the accompanying proxy statement/prospectus for more information related to the Sponsor Letter Agreement.

At any time at or prior to the Business Combination, during a period when they are not then aware of any material nonpublic information regarding us or our securities, our Initial Shareholders, Proterra and/or their directors, officers, advisors or respective affiliates may purchase public shares from institutional and other investors who vote, or indicate an intention to vote, against any of the Condition Precedent Proposals, or execute agreements to purchase such shares from such investors in the future, or they may enter into transactions with such investors and others to provide them with incentives to acquire public shares or vote their public shares in favor of the Condition Precedent Proposals. Such a purchase may include a contractual acknowledgement that such shareholder, although still the record or beneficial holder of our shares, is no longer the beneficial owner thereof and therefore agrees not to exercise its redemption rights. In the event that our Initial Shareholders, Proterra and/or their directors, officers, advisors or respective affiliates who have agreed to vote in favor of this transaction purchase shares in privately negotiated transactions from public shareholders who have already elected to exercise their redemption rights, such selling shareholder would be required to revoke their prior elections to redeem their shares. The purpose of such share purchases and other transactions would be to increase the likelihood of satisfaction of the requirements that (i) the Business Combination Proposal, the Governing Documents Proposals, the Nasdaq Proposal, the Equity Incentive Plan Proposal, the Employee Stock Purchase Plan Proposal and the Adjournment Proposal are approved by the affirmative vote of at least a majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled to vote on such matter (ii) the Domestication Proposal is approved by the affirmative vote of at least a two-thirds (2/3) majority of the votes cast by the holders of the issued ordinary shares present in person or represented by proxy at the extraordinary general meeting and entitled

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to vote on such matter, (iii) otherwise limit the number of public shares electing to redeem and (iv) New Proterra’s net tangible assets (as determined in accordance with Rule 3a51-1(g)(1) of the Exchange Act) being at least $5,000,001 after giving effect to the transactions contemplated by the Merger Agreement and the PIPE Financing.

If such transactions are effected, the consequence could be to cause the Business Combination to be consummated in circumstances where such consummation could not otherwise occur. Purchases of shares by the persons described above would allow them to exert more influence over the approval of the proposals to be presented at the extraordinary general meeting and would likely increase the chances that such proposals would be approved. We will file or submit a Current Report on Form 8-K to disclose any material arrangements entered into or significant purchases made by any of the aforementioned persons that would affect the vote on the proposals to be put to the extraordinary general meeting or the redemption threshold. Any such report will include descriptions of any arrangements entered into or significant purchases by any of the aforementioned persons.

The existence of financial and personal interests of one or more of ArcLight’s directors may result in a conflict of interest on the part of such director(s) between what he, she or they may believe is in the best interests of ArcLight and its shareholders and what he, she or they may believe is best for himself, herself or themselves in determining to recommend that shareholders vote for the proposals. In addition, ArcLight’s officers have interests in the Business Combination that may conflict with your interests as a shareholder.

Recommendation to Shareholders of ArcLight

The ArcLight Board believes that the Business Combination Proposal and the other proposals to be presented at the extraordinary general meeting are in the best interest of ArcLight and its shareholders and unanimously recommends that its shareholders vote “FOR” the Business Combination Proposal, “FOR” the Domestication Proposal, “FOR” each of the Governing Documents Proposals, “FOR” the Nasdaq Proposal, “FOR” the Equity Incentive Plan Proposal, “FOR” the Employee Stock Purchase Plan Proposal and “FOR” the Adjournment Proposal, in each case, if presented to the extraordinary general meeting.

The existence of financial and personal interests of one or more of ArcLight’s directors may result in a conflict of interest on the part of such director(s) between what he, she or they may believe is in the best interests of ArcLight and its shareholders and what he, she or they may believe is best for himself, herself or themselves in determining to recommend that shareholders vote for the proposals. In addition, ArcLight’s officers have interests in the Business Combination that may conflict with your interests as a shareholder. See the section entitled “Business Combination Proposal — Interests of ArcLight’s Directors and Executive Officers in the Business Combination” for a further discussion of these considerations.

Sources and Uses of Funds for the Business Combination

The following tables summarize the sources and uses for funding the Business Combination, assuming (i) none of ArcLight’s outstanding public shares are redeemed in connection with the Business Combination and (ii) all of ArcLight’s outstanding public shares are redeemed in connection with the Business Combination.

No Redemption

Source of Funds(1)
(in thousands)

 

Uses(1)
(in thousands)

Existing Cash held in trust account(2)

 

$

277,549

 

Shares of New Proterra Common Stock issued to the Proterra Holders(3)

 

$

1,648,638

Shares of New Proterra Common Stock issued to the Proterra Holders(3)

 

 

1,648,638

 

Transaction Fees and Expenses

 

 

45,000

PIPE Financing

 

 

415,000

 

Remaining Cash on Balance Sheet(4)

 

 

647,549

Total Sources

 

$

2,341,187

 

Total Uses

 

$

2,341,187

____________

(1)      Totals might be affected by rounding.

(2)      As of December 31, 2020.

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(3)      Shares issued to Proterra are at a deemed value of $10.00 per share based on 164,863,846 shares of New Proterra Common Stock expected to be issued at Closing. See “Unaudited Pro Forma Condensed Combined Financial Information” for more details.

(4)      Does not include outstanding warrants to purchase an aggregate of 21,425,000 shares of New Proterra Common Stock, which will become exercisable on the earlier to occur of (i) 30 days after closing of the Business Combination and (ii) September 25, 2021, at an exercise price of $11.50 per share.

Maximum Redemption

Source of Funds
(in thousands)

 

Uses
(in thousands)

Existing Cash held in trust account(2)

 

$

277,549

 

Shares of New Proterra Common Stock issued to the Proterra Holders(3)

 

$

1,675,120

Shares of New Proterra Common Stock issued to the Proterra Holders(3)

 

 

1,675,120

 

Transaction Fees and Expenses

 

 

45,000

   

 

   

ArcLight public redemption(4)

 

 

277,549

PIPE Financing

 

 

415,000

 

Remaining Cash on Balance Sheet(5)

 

 

370,000

Total Sources

 

$

2,367,669

 

Total Uses

 

$

2,367,669

____________

(1)      Totals might be affected by rounding.

(2)      As of December 31, 2020.

(3)      Shares issued to Proterra are at a deemed value of $10.00 per share based on 167,512,081 shares of New Proterra Common Stock expected to be issued at Closing. See “Unaudited Pro Forma Condensed Combined Financial Information” for more details.

(4)      Based on 27,750,000 shares subject to possible redemption, which assumes the maximum number of Class A ordinary shares that can be redeemed are redeemed, while still satisfying the Aggregate Transaction Proceeds Condition.

(5)      Does not include outstanding warrants to purchase an aggregate of 21,425,000 shares of New Proterra Common Stock, which will become exercisable on the later to occur of (i) 30 days after closing of the Business Combination and (ii) September 25, 2021, at an exercise price of $11.50 per share.

As a result of the transactions contemplated by the Merger Agreement, ArcLight expects New Proterra to add between $370 million and $647 million in cash on hand on its balance sheet as discussed above. Please see “Proterra’s Management’s Discussion and Analysis of Financial Condition and Results of Operation — Liquidity and Capital Resources” for more information.

U.S. Federal Income Tax Considerations

For a discussion summarizing the U.S. federal income tax considerations of the Domestication and exercise of redemption rights, please see “U.S. Federal Income Tax Considerations.”

Expected Accounting Treatment

The Domestication

There will be no accounting effect or change in the carrying amount of the consolidated assets and liabilities of ArcLight as a result of the Domestication. The business, capitalization, assets and liabilities and financial statements of New Proterra immediately following the Domestication will be the same as those of ArcLight immediately prior to the Domestication.

The Business Combination

The Business Combination will be accounted for as a reverse recapitalization in conformity with accounting principles generally accepted in the United States of America, or GAAP. Under this method of accounting, ArcLight has been treated as the “acquired” company for financial reporting purposes. This determination was primarily based on existing Proterra stockholders comprising a relative majority of the voting power of the combined company, Proterra’s operations prior to the acquisition comprising the only ongoing operations of New Proterra, Proterra’s senior management comprising a majority of the senior management of New Proterra, and Proterra will initially designate a majority of the board of directors of New Proterra. Accordingly, for accounting purposes, the financial

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statements of the combined entity will represent a continuation of the financial statements of Proterra with the Business Combination being treated as the equivalent of Proterra issuing stock for the net assets of ArcLight, accompanied by a recapitalization. The net assets of ArcLight will be stated at historical costs, with no goodwill or other intangible assets recorded.

Regulatory Matters

Under the HSR Act and the rules that have been promulgated thereunder by the U.S. Federal Trade Commission (“FTC”), certain transactions may not be consummated unless information has been furnished to the Antitrust Division of the Department of Justice (“Antitrust Division”) and the FTC and certain waiting period requirements have been satisfied. Certain aspects of the Business Combination are subject to these requirements and may not be completed until the expiration of a 30-day waiting period following the filing of the required Notification and Report Forms with the Antitrust Division and the FTC or until early termination is granted. ArcLight and Proterra filed the required forms under the HSR Act with the Antitrust Division and the FTC and requesting early termination in accordance with the Merger Agreement. The statutory HSR waiting period for the HSR Act expired on February 25, 2021.

At any time before or after consummation of the Business Combination, notwithstanding termination of the waiting period under the HSR Act, the applicable competition authorities in the United States or any other applicable jurisdiction could take such action under applicable antitrust laws as such authority deems necessary or desirable in the public interest, including seeking to enjoin the consummation of the Business Combination, conditionally approving the Business Combination upon divestiture of New Proterra’s assets, subjecting the completion of the Business Combination to regulatory conditions or seeking other remedies. Private parties may also seek to take legal action under the antitrust laws under certain circumstances. ArcLight cannot assure you that the Antitrust Division, the FTC, any state attorney general, or any other government authority will not attempt to challenge the Business Combination on antitrust grounds, and, if such a challenge is made, ArcLight cannot assure you as to its result.

None of ArcLight and Proterra are aware of any material regulatory approvals or actions that are required for completion of the Business Combination other than the expiration or early termination of the waiting period under the HSR Act. It is presently contemplated that if any such additional regulatory approvals or actions are required, those approvals or actions will be sought. There can be no assurance, however, that any additional approvals or actions will be obtained.

Emerging Growth Company

ArcLight is an “emerging growth company,” as defined in Section 2(a) of the Securities Act, as modified by the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and it may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies, including, but not limited to, not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002 (the “Sarbanes-Oxley Act”), reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved.

Further, Section 102(b)(1) of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies (that is, those that have not had a registration statement under the Securities Act declared effective or do not have a class of securities registered under the Exchange Act) are required to comply with the new or revised financial accounting standards. The JOBS Act provides that a company can elect to opt out of the extended transition period and comply with the requirements that apply to non-emerging growth companies but any such election to opt out is irrevocable. ArcLight has elected not to opt out of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, ArcLight, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard. This may make comparison of ArcLight’s financial statements with certain other public companies difficult or impossible because of the potential differences in accounting standards used.

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We will remain an emerging growth company until the earlier of: (i) the last day of the fiscal year (a) following the fifth anniversary of the closing of ArcLight’s initial public offering, (b) in which we have total annual gross revenue of at least $1.07 billion, or (c) in which we are deemed to be a large accelerated filer, which means the market value of our common equity that is held by non-affiliates exceeds $700 million as of the last business day of its most recently completed second fiscal quarter; and (ii) the date on which we have issued more than $1.00 billion in non-convertible debt securities during the prior three-year period. References herein to “emerging growth company” have the meaning associated with it in the JOBS Act.

Smaller Reporting Company

Additionally, we are a “smaller reporting company” as defined in Item 10(f)(1) of Regulation S-K. Smaller reporting companies may take advantage of certain reduced disclosure obligations, including, among other things, providing only two years of audited financial statements. We will remain a smaller reporting company until the last day of the fiscal year in which (i) the market value of our ordinary shares held by non-affiliates exceeds $250 million as of the prior June 30, or (ii) our annual revenues exceeded $100 million during such completed fiscal year and the market value of our ordinary shares held by non-affiliates exceeds $700 million as of the prior June 30.

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SELECTED HISTORICAL FINANCIAL INFORMATION OF ARCLIGHT

ArcLight is providing the following selected historical financial data to assist you in your analysis of the financial aspects of the Business Combination. ArcLight’s statement of operations data and cash flow data for the period from July 28, 2020 (inception) through December 31, 2020 and balance sheet data as of December 31, 2020 are derived from ArcLight’s audited financial statements contained in its Annual Report on Form 10-K for the year ended December 31, 2020 filed with the SEC and included elsewhere in this proxy statement/prospectus.

The information is only a summary and should be read in conjunction with ArcLight’s consolidated financial statements and related notes and “ArcLight’s Management’s Discussion and Analysis of Financial Condition and Results of Operations” contained elsewhere in this proxy statement/prospectus. ArcLight’s historical results are not necessarily indicative of future results, and the results for any interim period are not necessarily indicative of the results that may be expected for a full fiscal year.

 

For the
period from
July 28, 2020
(inception)
through
December 31,
2020

Statement of Operations Data:

 

 

 

 

General and administrative expenses

 

$

1,332,873

 

Net loss

 

$

(1,284,331

)

Weighted average Class A and Class B ordinary shares outstanding, basic and diluted

 

 

7,561,720

 

Basic and diluted net loss per Class A and Class B ordinary share

 

$

(0.18

)

   

 

 

 

Condensed Balance Sheet Data (At Period End):

 

 

 

 

Total assets

 

$

278,826,627

 

Total liabilities

 

$

10,920,462

 

Class A ordinary shares; 26,290,616 shares subject to possible redemption at 10.00 per share

 

$

262,906,160

 

Shareholder’s Equity

 

 

 

 

Class A ordinary shares, 0.0001 par value; 500,000,000 shares authorized; 1,459,384 shares issued and outstanding (excluding 26,290,616 shares subject to possible redemption)

 

$

146

 

Class B ordinary shares, $0.0001 par value; 50,000,000 shares authorized; 6,937,500 shares issued and outstanding

 

$

694

 

Total shareholders’ equity

 

$

5,000,005

 

   

 

 

 

Cash Flow Data: