You are cordially invited to attend a special meeting of stockholders of Livent Corporation (“Livent”). The meeting will be held virtually via live webcast on December 19, 2023, at 9:00 a.m. Eastern time. The meeting can be accessed by visiting www.virtualshareholdermeeting.com/LTHM2023SM. There will be no physical location for stockholders to attend. Whether or not you plan to attend, please vote your shares as promptly as possible.

As you may be aware, on May 10, 2023, Livent entered into a Transaction Agreement, which was subsequently amended by the Amendment to Transaction Agreement, dated as of August 2, 2023 and the Second Amendment to Transaction Agreement, dated as of November 5, 2023 (and as may further be amended from time to time, the “Transaction Agreement”), with Allkem Limited, an Australian public company limited by shares (“Allkem”), and Arcadium Lithium plc, a public limited company incorporated under the laws of the Bailiwick of Jersey (originally incorporated as Lightning-A Limited, a private limited company incorporated under the laws of the Bailiwick of Jersey and f/k/a Allkem Livent plc) (“NewCo”), which was subsequently joined by Lightning-A Merger Sub, Inc., a Delaware corporation (“Merger Sub”), providing for a combination of Livent and Allkem in a merger of equals transaction.

The Transaction Agreement provides that, if the transaction is approved by the Livent and Allkem shareholders, respectively, and the other conditions to closing the transaction are satisfied or waived at or prior to the closing of the transaction: (a) pursuant to a scheme of arrangement under Australian law (the “scheme”), each issued, fully paid ordinary share of Allkem will be exchanged for (i) where the Allkem shareholder has not elected to receive ordinary shares, par value $1.00 per share, of NewCo (each, a “NewCo Share”), one NewCo CHESS Depositary Instrument (a “CDI”) quoted on ASX representing a beneficial ownership interest (but not legal title) in one NewCo Share (with exceptions for certain jurisdictions in which Allkem shareholders may receive NewCo Shares unless they elect otherwise) and (ii) where the Allkem shareholder has elected to receive NewCo Shares, one NewCo Share (provided that, where an Allkem shareholder has a registered address in an ineligible jurisdiction, the Allkem shares of the ineligible Allkem shareholder will be transferred to a sale nominee prior to the scheme implementation, and the sale nominee will then be issued CDIs under the scheme and will subsequently sell all of the CDIs issued to it and remit a pro-rata share of the net proceeds of the sale of all of the CDIs issued to the sale nominee to each ineligible Allkem shareholder); and (b) as promptly as practicable after the scheme implementation, Merger Sub will merge with and into Livent, with Livent surviving the merger as a wholly owned subsidiary of NewCo (the “merger”), pursuant to which each share of Livent common stock, par value $0.001 per share (each, a “Livent Share”), other than certain excluded shares, will be converted into the right to receive 2.406 NewCo Shares. NewCo Shares are expected to be listed on the NYSE.

As a result of the transaction, each of Livent and Allkem will be a wholly owned subsidiary of NewCo, former Livent stockholders will become holders of NewCo Shares and former Allkem shareholders will become holders of NewCo Shares or CDIs. Immediately following the completion of the transaction, former Allkem shareholders are expected to own approximately 56% of NewCo and former Livent stockholders are expected to own approximately 44% of NewCo.

Together, Livent and Allkem expect to create a leading global lithium chemicals producer with the scale and global capabilities to better serve customers. The combined company will have a significant footprint of low-cost assets diversified across key geographies, products, and customers. We believe combining these two organizations will provide an enhanced value proposition for our customers, stockholders, employees and local communities, while maintaining our unwavering commitment to sustainability and responsible growth.

The Livent board of directors (the “Livent Board”) unanimously approved the Transaction Agreement and the transactions contemplated thereby and is calling the upcoming virtual special meeting at which Livent stockholders can vote upon a proposal to adopt the Transaction Agreement and approve the transactions contemplated thereby, including the merger. The Livent Board unanimously recommends that you vote “FOR” each of the proposals to be considered at the Livent special meeting, including the adoption of the Transaction Agreement and the approval of the transactions contemplated thereby, including the merger. The enclosed Notice of Special Meeting includes further details about the Livent special meeting.

You are welcome to virtually attend the Livent special meeting on December 19, 2023, but regardless of whether you plan to attend, please vote your shares via the instructions on page 9 of the enclosed proxy statement/prospectus and on the enclosed proxy card. Your vote is very important because the transaction cannot be completed unless holders of a majority of the outstanding Livent Shares entitled to vote on the adoption of the Transaction Agreement and the approval of the transactions contemplated thereby, including the merger, vote in favor of such adoption and approval, respectively. A failure to vote your shares on the proposal to adopt the Transaction Agreement and approve the transactions contemplated thereby, including the merger, will have the same effect as a vote against the proposal.

This document serves as (i) a proxy statement of Livent to solicit proxies for its special meeting of stockholders and (ii) a prospectus relating to the NewCo Shares to be issued to Livent stockholders as consideration in the merger. It contains answers to frequently asked questions and a summary of the important terms of the Livent special meeting, the Transaction Agreement and the transactions contemplated thereby, including the merger. A copy of the Transaction Agreement is attached as Annex A. We encourage you to read the proxy statement/prospectus, including its annexes and the documents incorporated by reference, carefully and in its entirety, including the section entitled “Risk Factors” beginning on page 37.

Thank you for your continued support.

Sincerely,

Neither the SEC nor any state securities commission has approved or disapproved of the transactions described herein or the securities to be issued under this proxy statement/prospectus or determined that this proxy statement/prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

The date of this proxy statement/prospectus is November 20, 2023 and it is first being mailed to Livent stockholders on or about November 20, 2023.

You are cordially invited to attend a special meeting of stockholders (the “Livent Special Meeting”). We will hold the meeting virtually via live webcast on December 19, 2023, at 9:00 a.m. Eastern time. The meeting can be accessed by visiting www.virtualshareholdermeeting.com/LTHM2023SM. There will be no physical location for stockholders to attend. The purpose of the Livent Special Meeting is to consider and vote upon the following proposals:

Accompanying this Notice of Special Meeting of Stockholders is a proxy statement/prospectus, which describes these proposals in more detail, and a form of proxy, which allows you to vote on these proposals. Please carefully review these materials, including the annexes to and information incorporated by reference into the proxy statement/prospectus. The Livent Board unanimously recommends that Livent stockholders vote “FOR” each of these proposals.

We welcome you to virtually attend the Livent Special Meeting, but whether or not you plan to attend, please submit your completed proxy via phone, mail or internet as soon as possible. Proxies are revocable and will not affect your right to vote during the special meeting in the event that you revoke the proxy and attend the virtual meeting. Instructions on how to vote are found in the sections titled “Information About the Livent Special Meeting—Voting of Proxies; Incomplete Proxies” and “Information about the Livent Special Meeting—Shares Held in Street Name and Broker Non-Votes” beginning on page 78 of the proxy statement/prospectus.

Only Livent stockholders of record as shown on our books at the close of business on November 14, 2023 will be entitled to vote at the Livent Special Meeting. Each Livent stockholder is entitled to one vote per Livent Share held by such Livent stockholder on all matters to be voted on at the meeting.

This proxy statement/prospectus, which forms part of a registration statement on Form S-4 filed with the SEC by NewCo, constitutes a prospectus of NewCo under Section 5 of the Securities Act of 1933, as amended (the “Securities Act”), with respect to the NewCo Shares to be issued to Livent stockholders pursuant to the Transaction Agreement.

This document also constitutes a proxy statement of Livent under Section 14(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). It also constitutes a notice of meeting with respect to the Livent Special Meeting, at which Livent stockholders will be asked to consider and vote upon the Livent Transaction Agreement Proposal, the Livent Advisory Compensation Proposal, the NewCo Advisory Governance Documents Proposals and the Livent Adjournment Proposal, each as described in more detail herein under “Information About the Livent Special Meeting.” NewCo Shares and CDIs to be issued in the transaction to holders of Allkem shares will be issued pursuant to an exemption from the registration requirements provided by Section 3(a)(10) of the Securities Act based on the approval of the scheme by the Court.

NewCo has supplied all information contained in this proxy statement/prospectus relating to NewCo, Livent has supplied all information contained in or incorporated by reference into this proxy statement/prospectus relating to Livent and Allkem has supplied all information contained in this proxy statement/prospectus relating to Allkem.

No person has been authorized to provide you with information that is different from what is contained in or incorporated by reference into this proxy statement/prospectus. This proxy statement/prospectus is dated November 20, 2023 and you should not assume that the information contained in this proxy statement/prospectus is accurate as of any date other than such date unless otherwise specifically provided herein. Further, you should not assume that the information incorporated by reference into this proxy statement/prospectus is accurate as of any date other than the date of the incorporated document. Neither the mailing of this proxy statement/prospectus to Livent stockholders nor the issuance by NewCo of NewCo Shares pursuant to the Transaction Agreement will create any implication to the contrary.

A copy of this document has been delivered to the Jersey Registrar of Companies (the “Registrar”) in accordance with Article 5 of the Companies (General Provisions) (Jersey) Order 2002, and the Registrar has given, and has not withdrawn, consent to its circulation. The Jersey Financial Services Commission (“JFSC”) has given, and has not withdrawn, its consent under Article 2 of the Control of Borrowing (Jersey) Order 1958 to the issue of NewCo Shares. The JFSC is protected by the Control of Borrowing (Jersey) Law 1947 against liability arising from the discharge of its functions under that law. It must be distinctly understood that, in giving these consents, neither the Registrar nor the JFSC takes any responsibility for the financial soundness of NewCo or for the correctness of any statements made, or opinions expressed, with regard to it. If you are in any doubt about the contents of this document you should consult your stockbroker, bank manager, solicitor, accountant or other financial adviser. The current directors of NewCo have taken all reasonable care to ensure that the facts stated in this document are true and accurate in all material respects, and that there are no other facts the omission of which would make misleading any statement in the document, whether of facts or of opinion. All such directors accept responsibility accordingly. It should be remembered that the price of securities and the income from them can go down as well as up.

Nothing in this document or anything communicated to holders or potential holders of the NewCo Shares or CDIs is intended to constitute or should be construed as advice on the merits of, the purchase of or subscription for, NewCo Shares or CDIs or the exercise of any rights attached to them for the purposes of the Financial Services (Jersey) Law 1998.

This proxy statement/prospectus incorporates important business and financial information about Livent from other documents that Livent has filed with the SEC, and that are contained in or incorporated by reference into this proxy statement/prospectus. For a listing of documents incorporated by reference into this proxy statement/prospectus, please see the section entitled “Where You Can Find More Information” beginning on page 301 of this proxy statement/prospectus. This information is available for you to review on the SEC’s website at www.sec.gov.

Any person may request copies of this proxy statement/prospectus and any of the documents incorporated by reference into this proxy statement/prospectus or other information concerning Livent, without charge, by written or telephonic request directed to Livent Corporation, 1818 Market Street, Suite 2550, Philadelphia, Pennsylvania 19103, Telephone: (215) 299-5900; or Morrow Sodali, LLC, Livent’s proxy solicitor, by calling toll-free at (800) 662-5200 or via email at Livent@info.morrowsodali.com.

In order for you to receive timely delivery of the documents in advance of the Livent Special Meeting to be held on December 19, 2023 you must request the information no later than five business days prior to the date of the Livent Special Meeting (i.e., by December 12, 2023).

Neither Allkem nor NewCo currently file reports with the SEC. Following the effectiveness of the registration statement of which this proxy statement/prospectus forms a part, NewCo will file annual, quarterly and current reports and other information with the SEC. SEC filings of NewCo will be available to the public at the SEC website at www.sec.gov.

Unless otherwise indicated or as the context otherwise requires, a reference in this proxy statement/prospectus to:

The following questions and answers are intended to briefly address some questions that you, as a Livent stockholder, may have regarding the transaction, the Transaction Agreement and the Livent Special Meeting. These questions and answers may not address all questions that may be important to you as a Livent stockholder. Please refer to the section entitled “Summary” beginning on page 17 of this proxy statement/prospectus and the more detailed information contained elsewhere in this proxy statement/prospectus, the annexes and the exhibits to and the information incorporated by reference into this proxy statement/prospectus, which you should read carefully and in their entirety. You may obtain the information incorporated by reference into this proxy statement/prospectus without charge by following the instructions under the section entitled “Where You Can Find More Information” beginning on page 301 of this proxy statement/prospectus.

The historical financial information of Livent included or incorporated by reference in this proxy statement/prospectus has been derived from the audited consolidated financial statements of Livent as of December 31, 2022 and 2021 and for each of the three years ended December 31, 2022, 2021 and 2020, which are included in the section entitled “Financial Statements and Supplementary Data” of Livent’s Annual Report on Form 10-K for the year ended December 31, 2022 filed with the SEC on February 24, 2023 incorporated by reference herein, as well as from the unaudited interim condensed consolidated financial statements as of September 30, 2023 and for the nine month periods ended September 30, 2023 and 2022, which are included in Livent’s Quarterly Report on Form 10-Q for the nine months ended September 30, 2023 incorporated by reference herein.

Livent’s consolidated financial statements are reported under GAAP and are presented in U.S. dollars.

The historical financial information of Allkem included in this proxy statement/prospectus has been derived from the audited consolidated financial statements of Allkem as of June 30, 2023 and 2022 and for each of the three fiscal years ended June 30, 2023, 2022 and 2021.

The historical consolidated financial statements of Allkem are reported under IFRS.

The unaudited pro forma condensed combined balance sheet included in this proxy statement/prospectus as of September 30, 2023, gives effect to the transaction as if the transaction had been completed on September 30, 2023, and has been prepared on a one-quarter lag basis and therefore combines the unaudited condensed consolidated balance sheet of Livent as of September 30, 2023, with Allkem’s audited consolidated balance sheet as of June 30, 2023, for the reason discussed below.

The unaudited pro forma condensed combined statement of operations included in this proxy statement/prospectus for the nine months ended September 30, 2023 and the year ended December 31, 2022, give effect to the transaction as if it had occurred on January 1, 2022, the first day of Livent’s fiscal year ended December 31, 2022 and combines the historical results of Livent and Allkem. The unaudited pro forma condensed combined statement of operations included in this proxy statement/prospectus for the fiscal year ended December 31, 2022, combines Livent’s audited consolidated statement of operations for the fiscal year ended December 31, 2022, and Allkem’s unaudited combined statement of profit or loss for the twelve months ended December 31, 2022, calculated as the audited consolidated statement of profit or loss for the year ended June 30, 2022, less the unaudited interim consolidated income statement for the six months ended December 31, 2021, plus the unaudited interim consolidated income statement for the six months ended December 31, 2022. The unaudited pro forma condensed combined statement of operations included in this proxy statement/prospectus for the nine months ended September 30, 2023 has been prepared on a one-quarter lag basis and therefore combines Livent’s interim unaudited condensed consolidated statement of operations for the nine months ended September 30, 2023, with Allkem’s unaudited statement of profit and loss for the nine months ended June 30, 2023 (the unaudited statement of profit or loss has been prepared by Allkem’s management for purposes of the unaudited pro forma condensed combined statement of operations and is not separately included in this proxy statement/prospectus since Allkem is not required to and does not publish quarterly financial statements).

For purposes of the unaudited pro forma condensed combined financial information, the applicable historical financial statements of Allkem have been reclassified to align to the financial statement presentation of Livent, adjusted for differences between IFRS and GAAP and adjusted for Livent’s accounting policies for material accounting policy differences. Further, the unaudited pro forma condensed combined financial information includes transaction accounting adjustments which are necessary to account for the transaction in accordance with GAAP. The unaudited pro forma adjustments are based upon available information and certain assumptions that Livent’s management believes are reasonable. See “Unaudited Pro Forma Condensed Combined Financial Information” for more information.

NewCo’s fiscal year end will be December 31 of each calendar year.

Certain numerical amounts included in this proxy statement/prospectus have been rounded for consistency of presentation. Certain totals in the tables included in this proxy statement/prospectus may not add up due to rounding.

References in this proxy statement/prospectus to “$,” “U.S.$” or “USD” are to U.S. dollars, references to “A$” or “AUD” are to Australian dollars and references to “€”or “EUR” are to euros.

The registration statement on Form S-4, of which this proxy statement/prospectus forms a part, and the documents incorporated by reference herein, contain “forward-looking statements,” including within the meaning of U.S. securities laws, with respect to, among other things, the businesses, strategies and plans of NewCo, Livent and Allkem, the future performance of the combined company, the perceived and potential synergies and other benefits of the transaction, and expectations around the financial impact of the transaction on NewCo’s financials, the intentions, beliefs and expectations, plans, strategies and objectives of the directors and management of the parties, the anticipated timing for and outcome and effects of the transaction (including expected benefits to stockholders of Livent and Allkem), anticipated production, production capacity or construction or development commencement dates, costs or production outputs, capital expenditure and future demand for lithium, market and industry trends, expectations for the ongoing development and growth potential of NewCo and the future operation of Allkem, Livent and NewCo. Forward-looking statements may be accompanied by words such as “believe,” “plan,” “anticipate,” “estimate,” “expect,” “intend,” “aim,” “potential,” “may,” “will,” “would,” “could,” “considered,” “likely,” “projection,” “future,” “forecast,” “guidance” or similar words, phrases or expressions, including variations of these words, phrases and expressions, but these are not the exclusive means of identifying such statements. Forward-looking statements are not statements of historical fact and actual events and results may differ materially from those contemplated by the forward-looking statements as a result of a variety of known and unknown risks, uncertainties, and other factors. While NewCo, Livent and Allkem believe the expectations, assumptions, estimates and projections respectively stated by them are reasonable, based on the assumptions made by and information currently available to the management of NewCo, Livent and Allkem, respectively, such forward-looking statements are only predictions and involve known and unknown risks and uncertainties, many of which are beyond the control of NewCo, Livent and Allkem. By their nature, forward-looking statements involve risk and uncertainty because they relate to future events and depend upon future circumstances that may or may not occur. Known and unknown risks, uncertainties and other factors may cause actual results to be materially different from any results, levels of activity, performance or achievements expressed or implied by any forward-looking statements. Actual results may differ materially from forward-looking statements and the current expectations of NewCo, Livent and Allkem depending upon a number of factors, including, but not limited to, risks, uncertainties and other factors discussed in the section of this proxy statement/prospectus entitled “Risk Factors” and in the section entitled “Risk Factors” in Livent’s Annual Report on Form 10-K for the year ended December 31, 2022, which is incorporated by reference herein, as well as those discussed in Livent’s periodic public filings with the SEC, including factors contained or incorporated by reference into such documents and in subsequent filings by Livent with the SEC, and the risks and uncertainties of, and other factors relating to, the following:

The foregoing list of risks, uncertainties and other factors is not exhaustive. You should carefully consider the foregoing risks, uncertainties and other factors and the other risks, uncertainties and factors that affect the parties’ businesses, including those described in this proxy statement/prospectus, and information contained in or incorporated by reference into this proxy statement/prospectus. See the section entitled “Where You Can Find More Information” beginning on page 301 of this proxy statement/prospectus.

None of NewCo, Livent or Allkem is under any obligation, and each expressly disclaim, any obligation, to update, alter or otherwise revise any forward-looking statements, whether written or oral, that may be made from time to time, whether as a result of new information, future events or otherwise. Persons reading this proxy statement/prospectus are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof.