First Supplemental Indenture, dated January 4, 2024, by and among Livent Corporation, Arcadium Lithium plc and U.S. Bank Trust Company, National Association

FIRST SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”), dated as of January 4, 2024, by and among ARCADIUM LITHIUM PLC, a public limited company incorporated under the laws of the Bailiwick of Jersey (“NewCo”), LIVENT CORPORATION, a Delaware corporation (the “Company”), and U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION (as successor-in-interest to U.S. Bank National Association), as trustee (the “Trustee”).

WHEREAS, the Company and the Trustee are parties to that certain Indenture, dated as of June 25, 2020, by and between the Company and the Trustee (the “Indenture”), pursuant to which the Company issued its 4.125% Convertible Senior Notes due 2025 (the “Notes”);

WHEREAS, on May 10, 2023, the Company entered into a Transaction Agreement, which was subsequently amended by the Amendment to Transaction Agreement, dated as of August 2, 2023, the Second Amendment to Transaction Agreement, dated as of November 5, 2023 and the Third Amendment to Transaction Agreement, dated as of December 20, 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 NewCo, which was subsequently joined by Lightning-A Merger Sub, Inc., a Delaware corporation (“Merger Sub”), and Arcadium Lithium Intermediate IRL Limited, a private company limited by shares and incorporated and registered in Ireland, providing for a combination of the Company and Allkem in a merger of equals;

WHEREAS, in accordance with the Transaction Agreement, at the closing of the transactions contemplated thereby on the date hereof: (a) pursuant to a scheme of arrangement under Australian law (the “scheme”), each issued, fully paid ordinary share of Allkem was exchanged for (i) where the Allkem shareholder did not elect 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 the Australian Securities Exchange 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 did elect to receive NewCo Shares, one NewCo Share (provided that, where an Allkem shareholder had a registered address in an ineligible jurisdiction, the Allkem shares of the ineligible Allkem shareholder were transferred to a sale nominee prior to the scheme implementation, and the sale nominee was then issued CDIs under the scheme and subsequently sold all of the CDIs issued to it and remitted 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) after the scheme implementation, Merger Sub merged with and into the Company, with the Company surviving the merger as a wholly owned subsidiary of NewCo (the “Merger”), pursuant to which each share of Common Stock of the Company, other than certain excluded shares, was converted into the right to receive 2.406 NewCo Shares, which NewCo Shares are listed on the New York Stock Exchange;

WHEREAS, as a result of the transactions consummated pursuant to the Transaction Agreement, each of Livent and Allkem became a wholly owned subsidiary of NewCo, former Company stockholders became holders of NewCo Shares and former Allkem shareholders became holders of NewCo Shares or CDIs;

WHEREAS, Section 11.01 of the Indenture permits the Company to merge with and into another Person so long as (a) the Company is the surviving Person in such merger, and (b) immediately after giving effect to such merger, no Default or Event of Default shall have occurred and be continuing under the Indenture;

WHEREAS, the Company was the surviving Person in the Merger, and immediately after giving effect to the Merger, no Default or Event of Default had occurred or was continuing under the Indenture;

WHEREAS, Section 14.07(a)(ii) of the Indenture provides that, in the case of any consolidation, merger or combination involving the Company as a result of which the Common Stock would be converted into, or exchanged for, stock, other securities, other property or assets (including cash or any combination thereof) (any such event, a “Merger Event”), then, at and after the effective time of such Merger Event, the right to convert each $1,000 principal amount of Notes shall be changed into a right to convert such principal amount of Notes into the kind and amount of shares of stock, other securities or other property or assets (including cash or any combination thereof) that a holder of a number of shares of Common Stock equal to the Conversion Rate immediately prior to such Merger Event would have owned or been entitled to receive (the “Reference Property,” with each “unit of Reference Property” meaning the kind and amount of Reference Property that a holder of one share of Common Stock is entitled to receive) upon such Merger Event and, prior to or at the effective time of such Merger Event, the Company or the successor or purchasing Person, as the case may be, shall execute with the Trustee a supplemental indenture permitted under Section 10.01(g) providing for such change in the right to convert each $1,000 principal amount of Notes; provided, however, that at and after the effective time of the Merger Event (A) the Company shall continue to have the right to determine the form of consideration to be paid or delivered, as the case may be, upon conversion of Notes in accordance with Section 14.02 and (B) (I) any amount payable in cash upon conversion of the Notes in accordance with Section 14.02 shall continue to be payable in cash, (II) any shares of Common Stock that the Company would have been required to deliver upon conversion of the Notes in accordance with Section 14.02 shall instead be deliverable in the amount and type of Reference Property that a holder of that number of shares of Common Stock would have been entitled to receive in such Merger Event and (III) the Daily VWAP shall be calculated based on the value of a unit of Reference Property;

WHEREAS, the Merger is a Merger Event, the NewCo Shares are the Reference Property, and a unit of Reference Property is 2.406 NewCo Shares, which is the merger consideration with respect to each share of Common Stock of the Company (other than certain excluded shares) in the Merger;

WHEREAS, in accordance with Section 14.07(a)(ii), the Company, NewCo and the Trustee desire to execute a supplemental indenture providing that the right to convert each $1,000 principal amount of Notes shall be changed into a right to convert such principal amount of Notes into 275.459331 NewCo Shares, which is the Conversion Rate of 114.4885 shares of Common Stock per $1,000 principal amount of Notes multiplied by 2.406 NewCo Shares;

WHEREAS, Section 10.01(g) provides that, without the consent of any Holder, the Company, when authorized by the resolutions of the Board of Directors, and the Trustee, at the Company’s expense, may from time to time and at any time enter into a supplemental indenture in connection with a Merger Event to provide that the Notes are convertible into Reference Property, subject to the provisions of Section 14.02, and make such related changes to the terms of the Notes to the extent expressly required by Section 14.07, and the Company, NewCo and the Trustee desire to enter into this Supplemental Indenture in order to do so and to comply with Section 14.07(a)(ii); and

WHEREAS, all conditions for the execution and delivery of this Supplemental Indenture have been complied with or have been done or performed.

NOW, THEREFORE, THIS FIRST SUPPLEMENTAL INDENTURE WITNESSETH:

In consideration of the foregoing and for other good and valuable consideration, receipt of which is hereby acknowledged, the Company, NewCo and the Trustee agree as follows for the equal and ratable benefit of the holders of the Notes:

IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed and attested, all as of the date first written above.