ALTM / Arcadium Lithium plc - SEC Filings, Annual Report, Proxy Statement

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1) ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2024 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to . Commission file number 001-38694 ARCA

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. Commission File Number: 001-41907 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in it

As filed with the Securities and Exchange Commission on March 7, 2025

As filed with the Securities and Exchange Commission on March 7, 2025 Registration No.

As filed with the Securities and Exchange Commission on March 7, 2025

As filed with the Securities and Exchange Commission on March 7, 2025 Registration No.

Articles of Association of Arcadium Lithium plc, adopted on March 6, 2025

Exhibit 3.1 Arcadium Lithium plc Articles of Association Contents Table of contents 1 Preliminary 1 1.1 Definitions and interpretation 1 1.2 Standard Table not to apply 4 1.3 Exercising powers 5 1.4 Currency 5 2 Share capital 6 2.1 Share capital and share issues 6 2.2 Rights attaching to ordinary shares 6 2.3 Series or classes of preferred shares 6 2.4 Rights of preferred shares 6 2.5 Effect of St

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): March 6, 2025 (March 5, 2025) ARC

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): March 6, 2025 (March 5, 2025) ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of inco

EX-99.25

NOTIFICATION OF THE REMOVAL FROM LISTING AND REGISTRATION OF THE STATED SECURITIES The New York Stock Exchange hereby notifies the SEC of its intention to remove the entire class of the stated securities from listing and registration on the Exchange at the opening of business on March 17, 2025, pursuant to the provisions of Rule 12d2-2 (a).

Third Supplemental Indenture

Exhibit 4.1 THIRD SUPPLEMENTAL INDENTURE THIRD SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”), dated as of March 6, 2025, by and among LIVENT CORPORATION, a Delaware corporation (the “Company”), ARCADIUM LITHIUM PLC, a public limited company incorporated under the laws of the Bailiwick of Jersey (“Arcadium”), and U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION (as successor-in-interest to U.

Notice to holders of Arcadium Lithium CDIs – Closing timetable for the proposed acquisition of Arcadium Lithium by Rio Tinto

Exhibit 99.1 Notice to holders of Arcadium Lithium CDIs – Closing timetable for the proposed acquisition of Arcadium Lithium by Rio Tinto New York, Sydney, 28 February 2025: As disclosed to the ASX on 14 February 20251, Arcadium Lithium plc (NYSE: ALTM, ASX: LTM, “Arcadium Lithium”), received all required pre-closing regulatory approvals in connection with the proposed acquisition of Arcadium Lith

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 28, 2025 ARCADIUM LITHIU

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 28, 2025 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

Acquisition Incentive Award Letter -

123 Main Avenue | 2nd Floor | City, State | 12345 | Office: +1 (000) 123 4567 | arcadiumlithium.

Consent of Carl Pednault, WSP Canada Inc., Whabouchi

ex238altm2024whabouchico #97274228v2 Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Carl Pednault, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) February 27, 2025 ARCADIUM LITHIU

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) February 27, 2025 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

Consent of Marc Rougier, WSP Canada Inc., Whabouchi

ex2372024whabouchiqpcons #97274228v2 Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Marc Rougier, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date

Consent of Montgomery & Associates Consultores Limitada, Sal de Vida

ex2311altm2024qpconsents CONSENT OF QUALIFIED PERSON Montgomery & Associates, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Sal de Vida Lithium Brine Project” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Consent of Marek Dworzanowski, Cauchari

ex2313arcadium-2024qpcon CONSENT OF QUALIFIED PERSON I, Marek Dworzanowski, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consent to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Cauchari Lithium Brine Project” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Barbara Fochtman, dated November 20, 2024

123 Main Avenue | 2nd Floor | City, State | 12345 | Office: +1 (000) 123 4567 | arcadiumlithium.

Arcadium Lithium plc Statement of Policy Concerning Trading in Company Securities, as of January 4, 2024

1 #97378145v8 ARCADIUM LITHIUM PLC STATEMENT OF POLICY CONCERNING TRADING IN COMPANY SECURITIES Adopted effective as of January 4, 2024 TABLE OF CONTENTS Page No.

Consent of Frederik Reidel, Managing Director of Atacama Water SpA, Cauchari

ex2314altm-2024qpconsent CONSENT OF QUALIFIED PERSON I, Frederik Reidel, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consent to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Cauchari Lithium Brine Project” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Acquisition Incentive Award Letter - Sara

123 Main Avenue | 2nd Floor | City, State | 12345 | Office: +1 (000) 123 4567 | arcadiumlithium.

Consent of Gunn Metallurgy, Salar de Olaroz

ex2310altm2024qpconsent- CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Olaroz Lithium Facility” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Consent of Gunn Metallurgy, Sal de Vida

ex2312altm2024qpconsents CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Sal de Vida Lithium Brine Project” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Description of Ordinary Shares

Exhibit 4.1 DESCRIPTION OF ORDINARY SHARES The following is a summary of the material terms of Arcadium Lithium plc’s (“Arcadium”) ordinary shares (each, an “Arcadium Share”) and preferred shares. This summary does not purport to be complete and is qualified in its entirety by reference to Jersey law and Arcadium’s Memorandum of Association and Articles of Association. References in this section t

FY 2024

Exhibit 99.1 News Release – February 27, 2025 Arcadium Lithium Releases Fourth Quarter and Full Year 2024 Results PHILADELPHIA and PERTH, Australia, February 27, 2025 /PRNewswire/ - Arcadium Lithium plc (NYSE: ALTM, ASX: LTM, “Arcadium Lithium” or the “Company”) today reported results for the fourth quarter and full year of 2024. As a result of its pending acquisition by Rio Tinto, announced on Oc

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2024 ☐ Transition Report Pursuant to Secti

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2024 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File Number 001-38694 ARCADIUM

Consent of Hydrominex Geoscience, Salar de Olaroz

ex239altm2024olarozxqphy CONSENT OF QUALIFIED PERSON Hydrominex Geoscience, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Olaroz Lithium Facility” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Consent of SLR Consulting (Canada) Ltd., James Bay

ex2315slrevans20250227x SLR Consulting (Canada) Ltd. 55 University Ave., Suite 501, Toronto, ON M5J 2H7 1 February 27, 2025 Consent of Qualified Person SLR Consulting (Canada) Ltd., in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amend

Consent of WSP Canada Inc., James Bay

ex2317altm2024qpconsent- CONSENT OF QUALIFIED PERSON WSP Canada Inc., in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary James Bay Lithium Project” (as amended, the “Te

cquisition Incentive Award Letter -

123 Main Avenue | 2nd Floor | City, State | 12345 | Office: +1 (000) 123 4567 | arcadiumlithium.

Consent of Wave International Pty Ltd., James Bay

ex2316altm2024qpconsent- CONSENT OF QUALIFIED PERSON Wave International Pty Ltd., in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “Form 10-K”), consents to: the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary James Bay Lithium Project” (as amende

Subsidiaries of the Registrant

Exhibit 21 ARCADIUM LITHIUM PLC SIGNIFICANT SUBSIDIARIES OF THE REGISTRANT The following is a list of the Company’s consolidating subsidiaries, as of December 31, 2024, except for certain subsidiaries of the Registrant which do not, in the aggregate, constitute a significant subsidiary as that term is defined in Rule 12b-2 under the Securities Exchange Act of 1934.

TO THE HOLDERS OF LIVENT CORPORATION 4.125% CONVERTIBLE SENIOR NOTES DUE 2025 CUSIP No. 53814L AB4 ISIN No. US53814LAB45 LIVENT CORPORATION February 13, 2025

Exhibit 99.1 NOTICE TO THE HOLDERS OF LIVENT CORPORATION 4.125% CONVERTIBLE SENIOR NOTES DUE 2025 CUSIP No. 53814L AB4 ISIN No. US53814LAB45 LIVENT CORPORATION February 13, 2025 On October 9, 2024, Arcadium Lithium plc, a public limited company incorporated under the laws of the Bailiwick of Jersey (“Arcadium”), entered into a Transaction Agreement (the “Transaction Agreement”) with Rio Tinto West

Arcadium Lithium Receives All Required Regulatory Approvals Globally to Close Acquisition by Rio Tinto and Announces Court Hearing Date

Exhibit 99.1 Arcadium Lithium Receives All Required Regulatory Approvals Globally to Close Acquisition by Rio Tinto and Announces Court Hearing Date PHILADELPHIA and PERTH, Australia, February 13, 2025 / PRNewswire / - Arcadium Lithium plc (NYSE: ALTM, ASX: LTM, “Arcadium Lithium”), a leading global lithium chemicals producer, has now received all required pre-closing regulatory approvals in conne

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 13, 2025 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 13, 2025 ARCADIUM LITHIU

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 13, 2025 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

Entry into a Material Definitive Agreement

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 5, 2025 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

Entry into a Material Definitive Agreement, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): January 23, 2025 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

Commitment Letter, dated as of January 22, 2025, among Arcadium Lithium plc and Rio Tinto plc

Exhibit 10.1 COMMITMENT LETTER To: Arcadium Lithium plc (the "Company") Suite 12, Gateway Hub Shannon Airport House Shannon, Co. Clare V14 E370 Ireland For the attention of: Gilberto Antoniazzi, Chief Financial Officer January 22, 2025 US$200,000,000 sidecar term facility (the "Incremental Facility") and US$300,000,000 standalone term facility (the "New Facility", and together with the Incremental

SECOND SUPPLEMENTAL INDENTURE

Exhibit 4.1 SECOND SUPPLEMENTAL INDENTURE SECOND SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”), dated as of January 1, 2025, by and among LIVENT CORPORATION, a Delaware corporation (the “Company”), ARCADIUM LITHIUM PLC, a public limited company incorporated under the laws of the Bailiwick of Jersey (“Arcadium”), and U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION (as successor-in-interest t

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 1, 2025 ARCADIUM LITHIUM

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 1, 2025 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or o

Arcadium Lithium Announces Shareholder Approval of Proposed Rio Tinto Transaction and Provides Regulatory Update

Exhibit 99.1 Arcadium Lithium Announces Shareholder Approval of Proposed Rio Tinto Transaction and Provides Regulatory Update PHILADELPHIA and PERTH, Australia, Dec. 23, 2024 / PRNewswire / - Arcadium Lithium plc (NYSE: ALTM, ASX: LTM, “Arcadium Lithium”), a leading global lithium chemicals producer, today announced that it has obtained all requisite shareholder approvals in connection with the pr

Financial Statements and Exhibits, Other Events, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): December 23, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) INFORMATION REQUIRED IN PROXY STATEMENT SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Ame

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) INFORMATION REQUIRED IN PROXY STATEMENT SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confide

Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): December 13, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant  ☐ Check the appropriate box:  ☐ Preliminary Proxy Statement  ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☒ D

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): November 15, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

ALTM / Arcadium Lithium plc / VAN ECK ASSOCIATES CORP Passive Investment

SC 13G 1 arcadiumlithiumplc13g.htm SC 13G schedule13g.htm UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 Arcadium Lithium PLC (Name of Issuer) COMMON STOCK (Title of Class of Securities) G0508H110 (CUSIP Number) September 30, 2024 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to desi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended September 30, 2024 ☐ Transition Report Pursuant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended September 30, 2024 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File Number 001-38694 ARCADIUM LITHIUM

Q3 2024

Exhibit 99.1 News Release – November 7, 2024 Arcadium Lithium Releases Third Quarter 2024 Results PHILADELPHIA and PERTH, Australia, November 7, 2024 /PRNewswire/ - Arcadium Lithium plc (NYSE: ALTM, ASX: LTM, “Arcadium Lithium” or the “Company”) today reported results for the third quarter of 2024. As a result of its pending acquisition by Rio Tinto, announced on October 9, 2024 (the “Transaction”

Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) November 7, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

Table 1: Transaction Valuation

Calculation of Filing Fee Tables Table 1: Transaction Valuation Proposed Maximum Aggregate Value of Transaction Fee Rate Amount of Filing Fee Fees to be Paid 1 $ 6,328,649,040.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant  ☐ Check the appropriate box: ☒ Preliminary Proxy Statement  ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))  ☐ D

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) INFORMATION REQUIRED IN PROXY STATEMENT SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Ame

DEFA14A 1 dp219196defa14a.htm FORM DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) INFORMATION REQUIRED IN PROXY STATEMENT SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate b

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 9, 2024 ARCADIUM LITHIUM

CIK: 0001977303 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 9, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of in

Exhibit 4

Exhibit 4 Letter to Customer / Partner / Suppliers October 9, 2024 - Subject: Arcadium Lithium to be Acquired by Rio Tinto Dear [Customer / Partner / Supplier], As you may have seen, today we announced a definitive agreement under which Arcadium Lithium will be acquired by Rio Tinto, a global leader in the mining industry.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 9, 2024 ARCADIUM LITHIUM

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 9, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or o

Transaction Agreement, dated as of October 9, 2024, by and among the Company, Parent and Buyer

Exhibit 2.1 TRANSACTION AGREEMENT BY AND AMONG ARCADIUM LITHIUM PLC, RIO TINTO BM SUBSIDIARY LIMITED AND RIO TINTO WESTERN HOLDINGS LIMITED DATED AS OF OCTOBER 9, 2024 Table of Contents Contents Page Article I THE TRANSACTION 1 Section 1.1 The Transaction. 1 Section 1.2 Closing. 1 Section 1.3 Effective Time. 2 Article II PURCHASE OF COMPANY SHARES 2 Section 2.1 Purchase of Company Shares. 2 Sectio

Exhibit 5

Exhibit 5 Letter to Unions October 9, 2024 - Subject: Arcadium Lithium to be Acquired by Rio Tinto Dear [Argentinian Union Representative / Leader], As you may have seen, today we announced a definitive agreement under which Arcadium Lithium will be acquired by Rio Tinto, a global leader in the mining industry.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 9, 2024 ARCADIUM LITHIUM

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 9, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or o

Transaction Agreement, dated as of October 9, 2024, by and among the Company, Parent and Buyer

Exhibit 2.1 TRANSACTION AGREEMENT BY AND AMONG ARCADIUM LITHIUM PLC, RIO TINTO BM SUBSIDIARY LIMITED AND RIO TINTO WESTERN HOLDINGS LIMITED DATED AS OF OCTOBER 9, 2024 Table of Contents Contents Page Article I THE TRANSACTION 1 Section 1.1 The Transaction. 1 Section 1.2 Closing. 1 Section 1.3 Effective Time. 2 Article II PURCHASE OF COMPANY SHARES 2 Section 2.1 Purchase of Company Shares. 2 Sectio

Exhibit 3

Exhibit 3 Letter to Local Communities October 9, 2024 - Subject: Arcadium Lithium to be Acquired by Rio Tinto Dear [Local Community Leader/Representative], As you may have seen, today we announced a definitive agreement under which Arcadium Lithium will be acquired by Rio Tinto, a global leader in the mining industry.

Entry into a Material Definitive Agreement, Financial Statements and Exhibits

CIK: 0001977303 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 9, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of in

Exhibit 2

Exhibit 2

Exhibit 1

Exhibit 1 From: Arcadium Lithium Communications To: Arcadium Lithium Communications Bcc: dl-AllArcadiumLithiumStaff Subject: Arcadium Lithium to be Acquired by Rio Tinto Date: Wednesday, October 9, 2024 2:09:41 AM Attachments: Employee FAQ9Oct2024.

Joint Press Release dated October 9, 2024.

Exhibit 99.1 October 9, 2024 Dear Shareholders, As Chairman of Arcadium Lithium, I wanted to directly address the definitive agreement with Rio Tinto and outline why our Board of Directors believe this transaction is in your best interests. As we highlighted last month at our investor day, Arcadium Lithium has high-quality assets, a winning commercial strategy and robust growth plans. We are also

World-class lithium business to strengthen Rio Tinto’s position as global leader in energy transition commodities Counter-cyclical expansion into a high-growth market, aligned with Rio Tinto’s long-term strategy and disciplined capital allocation fra

Exhibit 99.1 October 9, 2024 Dear Shareholders, As Chairman of Arcadium Lithium, I wanted to directly address the definitive agreement with Rio Tinto and outline why our Board of Directors believe this transaction is in your best interests. As we highlighted last month at our investor day, Arcadium Lithium has high-quality assets, a winning commercial strategy and robust growth plans. We are also

Resource Extraction Payment Report

EXHIBIT 2.01 Resource Extraction Payment Report This exhibit to Form SD presents payments made by Arcadium Lithium to the U.S. federal government and foreign governments for the purpose of commercial development of lithium for the year ended December 31, 2023. The information within this report has been prepared and is presented in accordance with Rule 13q-1 (17 CFR 240.13q-1) under the Securities

XBRL INSTANCE DOCUMENT

0001977303 2023-01-01 2023-12-31 0001977303 1 2023-01-01 2023-12-31 0001977303 2 2023-01-01 2023-12-31 0001977303 3 2023-01-01 2023-12-31 0001977303 4 2023-01-01 2023-12-31 0001977303 5 2023-01-01 2023-12-31 0001977303 6 2023-01-01 2023-12-31 0001977303 7 2023-01-01 2023-12-31 0001977303 8 2023-01-01 2023-12-31 0001977303 9 2023-01-01 2023-12-31 0001977303 10 2023-01-01 2023-12-31 0001977303 11 20

XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT

Government of Argentina [Member] Government of the United States of America [Member] Government of China [Member] Government of Singapore [Member] Government of United Kingdom [Member] Jujuy Province Government [Member] Catamarca Province Government [Member] San Salvador de Jujuy (City) [Member] Jujuy Energy and Mining Society partners of Jujuy Province Government [Member] Government of Australia

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM SD Specialized Disclosure Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM SD Specialized Disclosure Report ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or organization) (Commission File Number) (IRS Employer Identification No.) 1818 Market Street Suite 12, Gateway Hub Suite 2550

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended June 30, 2024 ☐ Transition Report Pursuant to S

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended June 30, 2024 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File Number 001-38694 ARCADIUM LITHIUM PLC (

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) August 6, 2024 ARCADIUM LITHIUM P

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) August 6, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or or

ARCADIUM LITHIUM PLC CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited, in millions, except per share data) Three Months Ended June 30, Six Months Ended June 30, 2024 2023 (1) 2024 2023 (1) Revenue $ 254.5 $ 235.8 $ 515.7 $ 489.3 Costs of sa

Exhibit 99.1 News Release – August 6, 2024 Arcadium Lithium Releases Second Quarter 2024 Results •Realized Average Pricing of $17,200 / Product Metric Ton for Lithium Hydroxide and Carbonate in the Second Quarter •Tracking Towards High End of $60 to 80 million Cost Savings Guidance in 2024 and Accelerating Further Cost Reductions •Projecting a 25% Increase in Combined Lithium Hydroxide and Carbona

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) July 25, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or org

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) ☒ Filed by the Registrant ☐ Filed by a Party other than the Registrant Check the appropriate box ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Defin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.  ) ☒ Filed by the Registrant  ☐ Filed by a Party other than the Registrant Check the appropriate box  ☐ Preliminary Proxy Statement  ☐ Confidential, for Use of the Commission Only (as permitted by Rule

Arcadium Lithium plc Compensation Policy for Non-Employee Directors, effective January 4, 2024

#97172800v16 ARCADIUM LITHIUM PLC COMPENSATION POLICY FOR NON-EMPLOYEE DIRECTORS (Effective as of January 4, 2024) PART I - GENERAL PROVISIONS 1.

Arcadium Lithium plc Executive Severance Guidelines for Corporate Officers

#97172808v4 Arcadium Lithium plc Executive Severance Guidelines Background The intent of these severance guidelines (“Guidelines”) is to provide executive officers of Arcadium Lithium plc (the “Company”) with reasonable transition benefits in the event of a termination of employment without cause (including, without limitation, a termination of employment by the executive officer due to (i) the executive officer’s job being eliminated due to duplication; (ii) significant adverse change in the size or scope of the position; and (iii) change in the location of the position that the executive officer cannot accept, but other than in the context of a change in control, or as a result of death, disability or retirement).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended March 31, 2024 ☐ Transition Report Pursuant to

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended March 31, 2024 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File Number 001-38694 ARCADIUM LITHIUM PLC

Form of Non-Employee Director Global Restricted Share Unit Award Agreement Under the Arcadium Lithium plc Omnibus Incentive Plan

#97588919v13 NON-EMPLOYEE DIRECTOR GLOBAL RESTRICTED SHARE UNIT AWARD AGREEMENT UNDER THE ARCADIUM LITHIUM PLC OMNIBUS INCENTIVE PLAN ANNUAL EQUITY GRANT This GLOBAL RESTRICTED SHARE UNIT AWARD AGREEMENT, including any additional terms or conditions for the Participant’s country set forth in any appendix attached hereto (the “Appendix,” and collectively with this Non-Employee Director Global Restricted Share Unit Award Agreement, (this “Agreement”), is made by and between Arcadium Lithium plc (the “Company”) and [Participant Name] (the “Participant”).

Form of Global Restricted Share Unit Award Agreement Under the Arcadium Lithium plc Omnibus Incentive Plan

#97588913v13 GLOBAL RESTRICTED SHARE UNIT AWARD AGREEMENT UNDER THE ARCADIUM LITHIUM PLC OMNIBUS INCENTIVE PLAN This GLOBAL RESTRICTED SHARE UNIT AWARD AGREEMENT, including any additional terms or conditions for the Participant’s country set forth in any appendix attached hereto (the “Appendix,” and collectively with this Global Restricted Share Unit Award Agreement, this “Agreement”) is made by and between Arcadium Lithium plc (the “Company”) and Participant Name (the “Participant”).

Form of Global Nonqualified Share Option Award Agreement Under the Arcadium Lithium plc Omnibus Incentive Plan

#97588909v12 GLOBAL NONQUALIFIED SHARE OPTION AWARD AGREEMENT UNDER THE ARCADIUM LITHIUM PLC OMNIBUS INCENTIVE PLAN This GLOBAL SHARE OPTION AWARD AGREEMENT, including any additional terms or conditions for the Participant’s country set forth in any appendix attached hereto (the “Appendix,” and collectively with this Global Nonqualified Share Option Award Agreement, this “Agreement”), is made by and between Arcadium Lithium plc (the “Company”) and Participant Name (the “Participant”).

ARCADIUM LITHIUM PLC CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited, in millions, except per share data) Three Months Ended March 31, 2024 2023 (1) Revenue $ 261.2 $ 253.5 Costs of sales 116.8 87.5 Gross margin 144.4 166.0 Selling, genera

Exhibit 99.1 News Release – May 7, 2024 Arcadium Lithium Releases First Quarter 2024 Results •Solid First Quarter Results Driven by Average Realized Pricing for Lithium Hydroxide and Carbonate of Over $20,000 / product metric ton •On Track to Achieve $60 to 80 million of Realized Synergies / Cost Savings in 2024 •Multiple Expansions Provide Pathway to 170,000 LCEs1 of Capacity by 2026 PHILADELPHIA

Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) May 7, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or organ

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 2)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 2) ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2023 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to . Commission file number 001-38694 ARCA

ALTM / Arcadium Lithium plc / VANGUARD GROUP INC - SCHEDULE 13G Passive Investment

SC 13G 1 tv0006-arcadiumlithiumplc.htm SCHEDULE 13G SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 Name of issuer: Arcadium Lithium PLC Title of Class of Securities: Common Stock CUSIP Number: G0508H110 Date of Event Which Requires Filing of this Statement: March 28, 2024 Check the appropriate box to designate the rule pursuant to w

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1) ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2023 ☐ Transition Repo

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A (Amendment No. 1) ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2023 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File Numbe

Financial Statements of Nemaska Lithium, Inc. for the year ended December 31, 2022

Nemaska Lithium Inc. Financial Statements (expressed in thousands of Canadian dollars, unless otherwise noted) For the years ended December 31, 2022 and 2021 Exhibit 99.1 Nemaska Lithium Inc. Index to Financial Statements Page Independent Auditors’ Report 1 Balance Sheets as at December 31, 2022 and 2021 4 Statements of Loss and Comprehensive Loss for the Years Ended December 31, 2022 and 2021 5 S

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) April 1, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or org

Nemaska Lithium Inc. Financial Statements (expressed in thousands of Canadian dollars, unless otherwise noted) For the years ended December 31, 2022 and 2021 Exhibit 99.1 Nemaska Lithium Inc. Index to Financial Statements Page Independent Auditors’ R

Nemaska Lithium Inc. Financial Statements (expressed in thousands of Canadian dollars, unless otherwise noted) For the years ended December 31, 2022 and 2021 Exhibit 99.1 Nemaska Lithium Inc. Index to Financial Statements Page Independent Auditors’ Report 1 Balance Sheets as at December 31, 2022 and 2021 4 Statements of Loss and Comprehensive Loss for the Years Ended December 31, 2022 and 2021 5 S

Arcadium Lithium plc Statement of Policy Concerning Trading in Company Securities, as of January 4, 2024

1 #97378145v8 ARCADIUM LITHIUM PLC STATEMENT OF POLICY CONCERNING TRADING IN COMPANY SECURITIES Adopted effective as of January 4, 2024 TABLE OF CONTENTS Page No.

Consent of Wave International Pty Ltd., James Bay

arcadium-formqpwaveinter Page 1 of 1 QV1‐ Level 3, 250 St Georges Tce, Perth Western Australia 6000 PO Box 7085, Cloisters Square Western Australia 6850 T / +61 (0)8 9204 0700 CONSENT OF QUALIFIED PERSON RE: Form 10‐K of Arcadium Lithium plc (the “Company”) Dear Sir/Madam: Wave International Pty Ltd, in connection with Arcadium Lithium plc’s Annual Report on Form 10‐K for the year ended December 3

Consent of Albert Thamm, Mt Cattlin

thammform10k-29022024ex2 Exhibit 23.8

Consent of Gunn Metallurgy, Salar de Olaroz

arcadqpconsent-gunnmetal CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Olaroz Lithium Facility” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Consent of Frederik Reidel, Managing Director of Atacama Water SpA, Cauchari

arcdmqpfrederikreidelex2 CONSENT OF QUALIFIED PERSON I, Frederik Reidel, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “Form 10-K”), consent to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Cauchari Lithium Brine Project” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Consent of Carl Pednault, WSP Canada Inc., Whabouchi

a2023qpconsent-carlpedna #97274228v2 Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Carl Pednault, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date

Consent of Hydrominex Geoscience, Salar de Olaroz

arcadium-qphydrominexgeo CONSENT OF QUALIFIED PERSON Hydrominex Geoscience, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Olaroz Lithium Facility” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Consent of Marc Rougier, WSP Canada Inc., Whabouchi

arcadium-formqpconsentxm Exhibit 23.7 #97274228v2 Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Marc Rougier, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original

Executive Severance Agreement dated February 23, 2024, by and between Arcadium Lithium plc and Paul Graves. Pursuant to Instruction 2 to Item 601 of Regulation S-K, an Executive Severance Agreement that is substantially identical in all material respects, except as to the parties thereto, between Arcadium Lithium plc and Gilberto Antoniazzi was not filed.

#113189964 v2 #97955201v2 EXECUTIVE SEVERANCE AGREEMENT This EXECUTIVE SEVERANCE AGREEMENT is made and entered into as of February 23, 2024 (the “Effective Date”), by and between Arcadium Lithium plc, a public limited company incorporated under the laws of the Bailiwick of Jersey (hereinafter referred to as the “Company”) and Paul W.

Consent of Marek Dworzanowski, Cauchari

arcadiumqpmdworzanowskie CONSENT OF QUALIFIED PERSON I, Marek Dworzanowski, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “Form 10-K”), consent to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Cauchari Lithium Brine Project” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Executive Severance Agreement dated February 23, 2024, by and between Arcadium Lithium plc and Sara Velazquez Ponessa.

#113189964 v2 #97955151v2 EXECUTIVE SEVERANCE AGREEMENT This EXECUTIVE SEVERANCE AGREEMENT is made and entered into as of February 23, 2024 (the “Effective Date”), by and between Arcadium Lithium plc, a public limited company incorporated under the laws of the Bailiwick of Jersey (hereinafter referred to as the “Company”) and Sara Velazquez Ponessa (hereinafter referred to as the “Executive”) (this “Agreement”).

Consent of Mining Plus Pty Ltd., Mt Cattlin

consentsk1300arcadiumexh CONSENT OF QUALIFIED PERSON Mining Plus Pty Ltd., in connection with Arcadium Lithium plc's Annual Report on Form 10-K for the year ended December 31, 2023 (the "Form 10-K"), consents to: • the use by Arcadium Lithium plc (the "Company") of and references to the amended technical report summary titled "SEC Technical Report Summary, Mt Cattlin" (as amended, the "Technical R

Consent of Gunn Metallurgy, Sal de Vida

arcadium-qpconsentxgunnm CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Sal de Vida Lithium Brine Project” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Consent of SLR Consulting (Canada) Ltd., James Bay

slr20240223xarcadiumjam SLR Consulting (Canada) Ltd. 55 University Ave., Suite 501, Toronto, ON M5J 2H7 Consent of Qualified Person Re: Form 10-K of Arcadium Lithium plc (the “Company”) SLR Consulting (Canada) Ltd. (“SLR”), in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the

Consent of Montgomery & Associates Consultores Limitada, Sal de Vida

arcadium-qpconsentxmontg CONSENT OF QUALIFIED PERSON Montgomery & Associates, in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, Sal de Vida Lithium Brine Project” (as amended, the “Technical Report Summary”), originally dated August 31, 2023 and amended on November 15, 2023, that was prepared in accordance with Subpart 1300 of Regulation S-K promulgated by the U.

Subsidiaries of the Registrant

Exhibit 21 ARCADIUM LITHIUM PLC SIGNIFICANT SUBSIDIARIES OF THE REGISTRANT The following is a list of the Company’s consolidating subsidiaries, as of December 31, 2023, except for certain subsidiaries of the Registrant which do not, in the aggregate, constitute a significant subsidiary as that term is defined in Rule 12b-2 under the Securities Exchange Act of 1934.

Consent of WSP Canada Inc., James Bay

arcadium-formqpconsentws CONSENT OF QUALIFIED PERSON WSP Canada Inc., in connection with Arcadium Lithium plc’s Annual Report on Form 10-K for the year ended December 31, 2023 (the “Form 10-K”), consents to: • the use by Arcadium Lithium plc (the “Company”) of and references to the amended technical report summary titled “SEC Technical Report Summary, James Bay Lithium Project” (as amended, the “T

Arcadium Lithium plc Financial Restatement Clawback Policy, effective as of January 4, 2024

Exhibit 97.1 #97450216v3 ARCADIUM LITHIUM PLC FINANCIAL RESTATEMENT CLAWBACK POLICY (Effective as of January 4, 2024) This Arcadium Lithium Plc (the “Company”) Financial Restatement Clawback Policy (the “Policy”) provides for the recoupment of certain executive compensation in the event of an accounting restatement resulting from material noncompliance with financial reporting requirements under U

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2023 ☐ Transition Report Pursuant to Secti

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the fiscal year ended December 31, 2023 or ☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission File Number 001-38694 ARCADIUM

Description of Ordinary Shares

Exhibit 4.1 DESCRIPTION OF ORDINARY SHARES The following is a summary of the material terms of Arcadium Lithium plc’s (“Arcadium”) ordinary shares (each, an “Arcadium Share”) and preferred shares. This summary does not purport to be complete and is qualified in its entirety by reference to Jersey law and Arcadium’s Memorandum of Association and Articles of Association. References in this section t

Arcadium Lithium plc Executive Severance Plan, dated as of February 21, 2024, with Form Agreement

Exhibit 10.21 #113189964 v2 #97172798v8 ARCADIUM LITHIUM PLC (the “Company”) CHANGE IN CONTROL EXECUTIVE SEVERANCE PLAN (dated February 21, 2024) 1. Purpose. The purpose of the Plan is to ensure that the Company will have the continued dedication and the availability of objective advice and counsel from key executives of the Company, notwithstanding the possibility, threat or occurrence of a bid t

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A Amendment No. 1 CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 4, 2024

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A Amendment No. 1 CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 4, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-41907 98-1737136 (State or other jurisdiction of

Unaudited pro forma condensed combined financial information of Arcadium Lithium plc

Exhibit 99.1 UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION Introduction On January 4, 2024 (the “Closing Date”), Arcadium Lithium plc (“Arcadium”) completed the previously announced transactions (collectively, the “transaction”) contemplated by the Transaction Agreement, dated as of May 10, 2023, as amended by the Amendment to Transaction Agreement, dated as of August 2, 2023, the S

ARCADIUM LITHIUM PLC CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited, in millions, except per share data)

Exhibit 99.1 News Release – February 22, 2024 Arcadium Lithium Releases Fourth Quarter and Full Year 2023 Results and Provides 2024 Full Year Outlook •Merger Between Allkem and Livent Completed on January 4, 2024 •Arcadium Lithium 2024 Outlook Highlighted by a 40% Increase in Lithium Carbonate and Hydroxide Volumes as a Combined Company •Projecting $60 to 80 million of Realized Synergies / Cost Sa

Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) February 22, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or

Filing Fee Table

Exhibit 107 Calculation of Filing Fee Tables FORM S-8 Registration Statement Under the Securities Act of 1933 (Form Type) Arcadium Lithium plc (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered (1) Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee (7) Equity Ordinary Shares, par value $1.

Consent of DRA Americas Inc.

Exhibit 23.8 CONSENT OF QUALIFIED PERSON DRA Americas Inc. (“DRA”), in connection with Arcadium Lithium plc’s registration statement on Form S-8, including any amendments thereto (the “Registration Statement”), consents to: · the incorporation by reference in the Registration Statement and use of the technical report titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine

EX-99.25

NOTIFICATION OF THE REMOVAL FROM LISTING AND REGISTRATION OF THE STATED SECURITIES The New York Stock Exchange hereby notifies the SEC of its intention to remove the entire class of the stated securities from listing and registration on the Exchange at the opening of business on January 16, 2024, pursuant to the provisions of Rule 12d2-2 (a).

Consent of DRA Americas Inc.

Exhibit 23.7 CONSENT OF QUALIFIED PERSON DRA Americas Inc. (“DRA”), in connection with Arcadium Lithium plc’s registration statement on Form S-8, including any amendments thereto (the “Registration Statement”), consents to: · the incorporation by reference in the Registration Statement and use of the technical report titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine

Consent of Carl Pednault (WSP Canada Inc.)

Exhibit 23.11 Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Carl Pednault, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date of 8 September, 2023 an

Consent of Marc Rougier (WSP Canada Inc.)

Exhibit 23.9 Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Marc Rougier, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date of 8 September, 2023 and

Consent of SGS Geological Services

Exhibit 23.8 CONSENT OF QUALIFIED PERSON SGS Geological Services (“SGS”), in connection with Arcadium Lithium plc’s registration statement on Form S-8, including any amendments thereto (the “Registration Statement”), consents to: · the incorporation by reference in the Registration Statement and use of the technical report titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouch

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 4, 2024 ARCADIUM LITHIUM

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 4, 2024 ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 001-38694 98-1737136 (State or other jurisdiction of incorporation or o

Consent of BBA Inc.

Exhibit 23.7 CONSENT OF QUALIFIED PERSON BBA Inc. (“BBA”), in connection with Arcadium Lithium plc’s registration statement on Form S-8, including any amendments thereto (the “Registration Statement”), consents to: · the incorporation by reference in the Registration Statement and use of the technical report titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska

Joinder and First Amendment to Amended and Restated Credit Agreement, dated January 4, 2024, by and among Livent Corporation, Livent USA Corp., Arcadium Lithium plc, Arcadium Lithium Intermediate IRL Limited, Arcadium Lithium Financing IRL Limited, the guarantors party thereto from time to time, the lenders party thereto, the issuing banks party thereto and Citibank, N.A., as administrative agent (incorporated by reference to Exhibit 10.2 to the Registrant’s Current Report on Form 8-K, filed on January 4, 2024)

Exhibit 10.2 Execution Version JOINDER AND FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT JOINDER AND FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (this “Amendment”), 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 with registration number 148645 (“Arcadium”), ARCADIUM LITHIUM INTE

Consent of Marc Rougier (WSP Canada Inc.)

Exhibit 23.10 Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Marc Rougier, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date of 8 September, 2023 an

Arcadium Lithium plc Omnibus Incentive Plan

Exhibit 99.1 ARCADIUM LITHIUM plc OMNIBUS INCENTIVE PLAN (Adopted effective as of January 4, 2024) Article 1 Purpose Section 1.01. Purpose. The purpose of the Arcadium Lithium plc Omnibus Incentive Plan (as may be amended from time to time, the “Plan”) is to give the Company a competitive advantage in attracting, retaining and motivating officers, employees, directors and consultants of Arcadium L

Filing Fee Table

Exhibit 107.1 Calculation of Filing Fee Tables FORM S-8 Registration Statement Under the Securities Act of 1933 (Form Type) Arcadium Lithium plc (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered (1) Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Am

FORM OF INDEMNIFICATION AGREEMENT

Exhibit 10.6 FORM OF INDEMNIFICATION AGREEMENT This Indemnification Agreement (this “Agreement”), is made and entered into as of the [●] day of [●], [●], by and between Arcadium Lithium plc, a public limited company incorporated under the laws of the Bailiwick of Jersey (the “Company”) and [●] (“Indemnitee”). W I T N E S S E T H: WHEREAS, the Board of Directors of the Company (the “Board”) has det

Consent of SGS Geological Services

Exhibit 23.9 CONSENT OF QUALIFIED PERSON SGS Geological Services (“SGS”), in connection with Arcadium Lithium plc’s registration statement on Form S-8, including any amendments thereto (the “Registration Statement”), consents to: · the incorporation by reference in the Registration Statement and use of the technical report titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouch

As filed with the Securities and Exchange Commission on January 4, 2024

As filed with the Securities and Exchange Commission on January 4, 2024 Registration No.

Arcadium Lithium Announces Completion of Merger of Equals between Allkem and Livent Combination Creates a Leading Global Integrated Lithium Chemicals Producer

Exhibit 99.1 Arcadium Lithium Announces Completion of Merger of Equals between Allkem and Livent Combination Creates a Leading Global Integrated Lithium Chemicals Producer Key Strengths ● Leading global lithium chemicals producer with the resources, scale and expertise to meet growing customer and industry needs − reliably, safely and responsibly. ● Premier lithium resources and manufacturing site

Arcadium Lithium plc Omnibus Incentive Plan (incorporated by reference to Exhibit 10.

Exhibit 10.7 ARCADIUM LITHIUM plc OMNIBUS INCENTIVE PLAN (Adopted effective as of January 4, 2024) Article 1 Purpose Section 1.01. Purpose. The purpose of the Arcadium Lithium plc Omnibus Incentive Plan (as may be amended from time to time, the “Plan”) is to give the Company a competitive advantage in attracting, retaining and motivating officers, employees, directors and consultants of Arcadium L

First Supplemental Indenture, dated January 4, 2024, by and among Livent Corporation, Arcadium Lithium plc and U.S. Bank Trust Company, National Association (incorporated by reference to Exhibit 4.2 to the Registrant’s Current Report on Form 8-K, filed on January 4, 2024)

Exhibit 4.2 FIRST SUPPLEMENTAL INDENTURE 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

Consent of Carl Pednault (WSP Canada Inc.)

Exhibit 23.10 Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Carl Pednault, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date of 8 September, 2023 an

As filed with the Securities and Exchange Commission on January 4, 2024

As filed with the Securities and Exchange Commission on January 4, 2024 Registration No.

Articles of Association of the Registrant, as amended, effective as of December 20, 2023 (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K, dated as of December 27, 2023)

Exhibit 3.1 Arcadium Lithium plc Articles of Association Table of contents Contents 1 Preliminary 1 1.1 Definitions and interpretation 1 1.2 Standard Table not to apply 4 1.3 Exercising powers 5 1.4 Currency 5 2 Share capital 6 2.1 Share capital and share issues 6 2.2 Rights attaching to ordinary shares 6 2.3 Series or classes of preferred shares 6 2.4 Rights of preferred shares 6 2.5 Effect of St

Third Amendment to Transaction Agreement, dated as of December 20, 2023, by and between Livent Corporation, a Delaware corporation, and Allkem Limited, an Australian public company limited by shares.

Exhibit 2.1 THIRD AMENDMENT TO TRANSACTION AGREEMENT This THIRD AMENDMENT TO TRANSACTION AGREEMENT (this “Amendment”), dated as of December 20, 2023, is by and between Livent Corporation, a Delaware corporation (“Livent”), and Allkem Limited, an Australian public company limited by shares (“Allkem”). Each of Livent and Allkem are referred to as a “Party,” and collectively, as the “Parties.” WHEREA

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Entry into a Material Definitive Agreement, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 27, 2023 (December 20, 2023) ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 333-273360 98-1737136 (State or other jurisdictio

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 20, 2023 (December 15, 2023) ARCADIUM LITHIUM PLC (Exact name of registrant as specified in its charter) Bailiwick of Jersey 333-273360 98-1737136 (State or other jurisdictio

1

Filed by Arcadium Lithium plc pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6 under the Securities Exchange Act of 1934 Subject Company: Livent Corporation Commission File No.

Filed by Arcadium Lithium plc

Filed by Arcadium Lithium plc pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6 under the Securities Exchange Act of 1934 Subject Company: Livent Corporation Commission File No.

Livent Announces Special Meeting Date to Vote on Pending Merger of Equals with Allkem; Form S-4 Registration Statement Declared Effective

Filed by Arcadium Lithium plc pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-6 under the Securities Exchange Act of 1934 Subject Company: Livent Corporation Commission File No.

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

TABLE OF CONTENTS Filed Pursuant to Rule 424(b)(3) File No. 333-273360   MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT To our Stockholders: 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.virtualshareh

[Signature Page Follows]

November 17, 2023 VIA EDGAR Ms. Julie Sherman Ms. Jane Park Division of Corporation Finance United States Securities and Exchange Commission 100 F Street N.E. Washington, D.C. 20549-3628 Re: Arcadium Lithium plc (f/k/a Allkem Livent plc) Registration Statement on Form S-4 File No. 333-273360 Dear Ms. Sherman and Ms. Park: Pursuant to Rule 461 under the Securities Act of 1933, as amended, Arcadium

CONSENT OF QUALIFIED PERSON

Exhibit 23.13 CONSENT OF QUALIFIED PERSON Hydrominex Geoscience, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summar

CONSENT OF QUALIFIED PERSON

Exhibit 23.17 CONSENT OF QUALIFIED PERSON Marek Dworzanowski, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary,

Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON

Exhibit 23.10 Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Marc Rougier, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date of 8 September 2023 and

SEC Technical Report Summary Cauchari Lithium Brine Project Prepared by: Marek Dworzanowski Metallurgical Engineer Frederik Reidel Managing Director, Atacama Water SpA Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Que

Exhibit 96.4 SEC Technical Report Summary Cauchari Lithium Brine Project Prepared by: Marek Dworzanowski Metallurgical Engineer and Frederik Reidel Managing Director, Atacama Water SpA Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000,Australia Report Date: August 31, 2023 Amended Date: November 15, 2023 Effective Date: June 30, 2023 Cauchari Lithium Br

As filed with the Securities and Exchange Commission on November 15, 2023

TABLE OF CONTENTS As filed with the Securities and Exchange Commission on November 15, 2023 Registration No.

CONSENT OF QUALIFIED PERSON

Exhibit 23.8 CONSENT OF QUALIFIED PERSON SGS Geological Services (“SGS”), in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consents to: • the use in connection with the Registration Statement of the amended technical report titled “Technica

Exhibit 23.22 CONSENT OF QUALIFIED PERSON

Exhibit 23.22 CONSENT OF QUALIFIED PERSON I, Sean Kosinski, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consent to: • the use in connection with the Registration Statement of, and references therein to, the amended technical report tit

SEC Technical Report Summary Olaroz Lithium Facility Prepared by: Hydrominex Geoscience 63 Carlotta St, Greenwich, NSW, 2065, Australia Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia Prepared for: Allkem Limited Riparian Plaza—Level 35 71

Exhibit 96.2 SEC Technical Report Summary Olaroz Lithium Facility Prepared by: Hydrominex Geoscience 63 Carlotta St, Greenwich, NSW, 2065, Australia and Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000, Australia Report Date: August 31, 2023 Amended Date: November 15, 2023 Effective Date: June

Exhibit 23.7 CONSENT OF QUALIFIED PERSON

Exhibit 23.7 CONSENT OF QUALIFIED PERSON DRA Americas Inc. (“DRA”), in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consents to: • the use in connection with the Registration Statement of the amended technical report titled “Technical Repo

CONSENT OF QUALIFIED PERSON

Exhibit 23.14 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Ola

CONSENT OF QUALIFIED PERSON

Exhibit 23.16 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Sal

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Michael Kaplan +1 212 450 4111 [email protected] Davis Polk & Wardwell LLP 450 Lexington Avenue New York, NY 10017 davispolk.com CONFIDENTIAL November 15, 2023 Re: Allkem Livent plc (n/k/a Arcadium Lithium plc) Amendment No. 3 to Registration Statement on Form S-4 Filed October 30, 2023 File No. 333-273360 Ms. Julie Sherman Ms. Jane Park Office of Industrial Applications and Services Di

SEC Technical Report Summary Sal de Vida Lithium Brine Project Prepared by: Montgomery & Associates Consultores Limitada 1550 East Prince Road, Tucson, Arizona 85719 United States of America Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia

Exhibit 96.3 SEC Technical Report Summary Sal de Vida Lithium Brine Project Prepared by: Montgomery & Associates Consultores Limitada 1550 East Prince Road, Tucson, Arizona 85719 United States of America and Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000, Australia Report Date: August 31, 202

CONSENT OF GORDON DYAL & CO., LLC

Exhibit 99.3 CONSENT OF GORDON DYAL & CO., LLC We hereby consent to the inclusion in the registration statement on Form S-4 of Arcadium Lithium plc (the “Registration Statement”) and in the proxy statement/prospectus included therein (the “Proxy Statement/Prospectus”), which forms part of the Registration Statement, of our written opinion, dated May 10, 2023, to the board of directors of Livent Co

Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON

Exhibit 23.9 Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Carl Pednault, state that I am responsible for preparing or supervising the preparation of parts of the amended technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with an original report date of 8 September 2023 and

CONSENT OF QUALIFIED PERSON

Exhibit 23.15 CONSENT OF QUALIFIED PERSON Montgomery & Associates Consultores Limitada, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC

CONSENT OF QUALIFIED PERSON

Exhibit 23.18 CONSENT OF QUALIFIED PERSON Frederik Reidel, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Cau

Memorandum of Association of the Registrant, as amended, effective as of November 9, 2023 (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K, dated as of January 4, 2024)

Exhibit 3.1 Companies (Jersey) Law 1991 Public Company Limited by Shares Memorandum of Association of Arcadium Lithium plc 1. The name of the Company is Arcadium Lithium plc. 2. The Company is a public company limited by shares. 3. The Company is a par value company. 4. The Company has unrestricted corporate capacity. 5. The liability of each member arising from his or her holding of a share is li

# # #

Filed by Arcadium Lithium plc pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Livent Corporation Commission File No.

1

Filed by Arcadium Lithium plc pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Livent Corporation Commission File No.

Filed by Arcadium Lithium plc

Filed by Arcadium Lithium plc pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Livent Corporation Commission File No.

Filed by Arcadium Lithium plc

Filed by Arcadium Lithium plc pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934 Subject Company: Livent Corporation Commission File No.

As filed with the Securities and Exchange Commission on October 30, 2023

As filed with the Securities and Exchange Commission on October 30, 2023 Registration No.

SEC Technical Report Summary Mt Cattlin Lithium Project Prepared by: Mining Plus Pty Ltd. Bravo Building, 1 George Wienke Drive, Perth Domestic Airport, WA 6105 Albert Thamm, F.Aus.IMM of Allkem Limited Prepared for: Allkem Limited Riparian Plaza—Lev

Exhibit 96.1 SEC Technical Report Summary Mt. Cattlin Lithium Project SEC Technical Report Summary Mt Cattlin Lithium Project Prepared by: Mining Plus Pty Ltd. Bravo Building, 1 George Wienke Drive, Perth Domestic Airport, WA 6105 and Albert Thamm, F.Aus.IMM of Allkem Limited Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000, Australia Report Date: Augu

CONSENT OF QUALIFIED PERSON

Exhibit 23.18 CONSENT OF QUALIFIED PERSON Frederik Reidel, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Cau

CONSENT OF QUALIFIED PERSON

Exhibit 23.14 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Ola

Consent of Qualified Person

Exhibit 23.19 SLR Consulting (Canada) Ltd. 55 University Ave., Suite 501, Toronto, ON M5J 2H7 October 30, 2023 Consent of Qualified Person SLR Consulting (Canada) Ltd. (“SLR”), in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Sta

CONSENT OF QUALIFIED THIRD PARTY FIRM

Exhibit 23.11 CONSENT OF QUALIFIED THIRD PARTY FIRM Mining Plus Pty Ltd, in connection with Arcadium Lithium plc’s registration statement on Form S4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report

CONSENT OF QUALIFIED PERSON

Exhibit 23.20 CONSENT OF QUALIFIED PERSON QV1- Level 3, 250 St Georges Tce, Perth Western Australia 6000 PO Box 7085, Cloisters Square Western Australia 6850 T / +61 (0)8 9204 0700 Dear Sir/Madam: RE: SEC TECHNICAL REPORT SUMMARY, JAMES BAY LITHIUM PROJECT Wave International Pty Ltd. in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus inc

CONSENT OF GORDON DYAL & CO., LLC

Exhibit 99.3 CONSENT OF GORDON DYAL & CO., LLC We hereby consent to the inclusion in the registration statement on Form S-4 of Arcadium Lithium plc (the “Registration Statement”) and in the proxy statement/prospectus included therein (the “Proxy Statement/Prospectus”), which forms part of the Registration Statement, of our written opinion, dated May 10, 2023, to the board of directors of Livent Co

Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON

Exhibit 23.10 Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Marc Rougier, state that I am responsible for preparing or supervising the preparation of parts of the technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with a report date of 8 September, 2023 as signed and certif

CONSENT OF QUALIFIED PERSON

Exhibit 23.15 CONSENT OF QUALIFIED PERSON Montgomery & Associates Consultores Limitada, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC

CONSENT OF QUALIFIED PERSON

Exhibit 23.16 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Sal

CONSENT OF QUALIFIED PERSON

Exhibit 23.17 CONSENT OF QUALIFIED PERSON Marek Dworzanowski, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary,

Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON

Exhibit 23.9 Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Carl Pednault, state that I am responsible for preparing or supervising the preparation of parts of the technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with a report date of 8 September, 2023 as signed and certifi

CONSENT OF QUALIFIED THIRD PARTY FIRM

Exhibit 23.11 CONSENT OF QUALIFIED THIRD PARTY FIRM Mining Plus Pty Ltd, in connection with Arcadium Lithium plc’s registration statement on Form S4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report

CONSENT OF QUALIFIED PERSON

Exhibit 23.12 CONSENT OF QUALIFIED PERSON Albert Thamm, F.Aus.IMM in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summa

CONSENT OF QUALIFIED PERSON

Exhibit 23.18 CONSENT OF QUALIFIED PERSON Frederik Reidel, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Cau

CONSENT OF QUALIFIED PERSON

Exhibit 23.21 CONSENT OF QUALIFIED PERSON WSP Canada Inc., in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary Jame

Technical Report Summary on James Bay Lithium Project, prepared by SLR Consulting (Canada) Ltd., Wave International Pty Ltd. and WSP Canada Inc., dated August 31, 2023 and amended October 30, 2023 (Exhibit 96.5 to Amendment No. 4 to the Registrant’s Registration Statement on Form S-4/A, filed on October 30, 2023)

Exhibit 96.5 SEC Technical Report Summary Allkem Limited James Bay Lithium Project Prepared by: SLR Consulting (Canada) Ltd. 55 University Ave., Suite 501 Toronto, ON M5J 2H7 Wave International Pty Ltd. QV1-Level 3, 250 St Georges Tce Perth, WA 6000 and WSP Canada Inc. 1600, Boulevard René-Lévesque, 11 étage Montréal, QC H3H 1P9 Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street

Technical Report Summary on Sal de Vida Lithium Brine Project, prepared by Montgomery & Associates Consultores Limitada and Gunn Metallurgy, dated August 31, 2023 and amended November 15, 2023 (Exhibit 96.3 to Amendment No. 4 to the Registrant’s Registration Statement on Form S-4/A, filed on November 15, 2023)

Exhibit 96.3 SEC Technical Report Summary Sal de Vida Lithium Brine Project Prepared by: Montgomery & Associates Consultores Limitada 1550 East Prince Road, Tucson, Arizona 85719 United States of America and Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000, Australia Report Date: August 31, 202

CONSENT OF QUALIFIED PERSON

Exhibit 23.21 CONSENT OF QUALIFIED PERSON WSP Canada Inc., in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary Jame

Primary Well Battery

Michael Kaplan +1 212 450 4111 [email protected] Davis Polk & Wardwell llp 450 Lexington Avenue New York, NY 10017 davispolk.com CONFIDENTIAL October 30, 2023 Re: Allkem Livent plc (n/k/a Arcadium Lithium plc) Amendment No. 1 to Registration Statement on Form S-4 Filed September 26, 2023 (Filing Date September 27, 2023) File No. 333-273360 Ms. Julie Sherman Ms. Jane Park Office of Indus

CONSENT OF QUALIFIED PERSON

Exhibit 23.20 CONSENT OF QUALIFIED PERSON QV1- Level 3, 250 St Georges Tce, Perth Western Australia 6000 PO Box 7085, Cloisters Square Western Australia 6850 T / +61 (0)8 9204 0700 Dear Sir/Madam: RE: SEC TECHNICAL REPORT SUMMARY, JAMES BAY LITHIUM PROJECT Wave International Pty Ltd. in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus inc

CONSENT OF QUALIFIED PERSON

Exhibit 23.13 CONSENT OF QUALIFIED PERSON Hydrominex Geoscience, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summar

CONSENT OF QUALIFIED PERSON

Exhibit 23.12 CONSENT OF QUALIFIED PERSON Albert Thamm, F.Aus.IMM in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summa

CONSENT OF QUALIFIED PERSON

Exhibit 23.14 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Ola

CONSENT OF QUALIFIED PERSON

Exhibit 23.15 CONSENT OF QUALIFIED PERSON Montgomery & Associates Consultores Limitada, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC

CONSENT OF QUALIFIED PERSON

Exhibit 23.17 CONSENT OF QUALIFIED PERSON Marek Dworzanowski, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary,

Consent of Qualified Person

Exhibit 23.19 SLR Consulting (Canada) Ltd. 55 University Ave., Suite 501, Toronto, ON M5J 2H7 October 30, 2023 Consent of Qualified Person SLR Consulting (Canada) Ltd. (“SLR”), in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Sta

Exhibit 23.7 CONSENT OF QUALIFIED PERSON

Exhibit 23.7 CONSENT OF QUALIFIED PERSON DRA Americas Inc. (“DRA”), in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consents to: • the use in connection with the Registration Statement of the technical report titled “Technical Report on th

CONSENT OF QUALIFIED PERSON

Exhibit 23.8 CONSENT OF QUALIFIED PERSON SGS Geological Services (“SGS”), in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consents to: • the use in connection with the Registration Statement of the technical report titled “Technical Report

Technical Report Summary on Cauchari Lithium Brine Project, prepared by Marek Dworzanowski and Frederik Reidel, dated August 31, 2023 and amended November 15, 2023 (Exhibit 96.4 to Amendment No. 4 to the Registrant’s Registration Statement on Form S-4/A, filed on November 15, 2023)

Exhibit 96.4 SEC Technical Report Summary Cauchari Lithium Brine Project Prepared by: Marek Dworzanowski Metallurgical Engineer and Frederik Reidel Managing Director, Atacama Water SpA Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000,Australia Report Date: August 31, 2023 Amended Date: October 30, 2023 Effective Date: June 30, 2023 Cauchari Lithium Bri

CONSENT OF QUALIFIED PERSON

Exhibit 23.13 CONSENT OF QUALIFIED PERSON Hydrominex Geoscience, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summar

CONSENT OF QUALIFIED PERSON

Exhibit 23.16 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Arcadium Lithium plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Sal

As filed with the Securities and Exchange Commission on October 30, 2023

TABLE OF CONTENTS As filed with the Securities and Exchange Commission on October 30, 2023 Registration No.

Technical Report Summary on Olaroz Lithium Facility, prepared by Hydrominex Geoscience and Gunn Metallurgy, dated August 31, 2023 and amended November 15, 2023 (Exhibit 96.2 to Amendment No. 4 to the Registrant’s Registration Statement on Form S-4/A, filed on November 15, 2023)

Exhibit 96.2 SEC Technical Report Summary Olaroz Lithium Facility Prepared by: Hydrominex Geoscience 63 Carlotta St, Greenwich, NSW, 2065, Australia and Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000, Australia Report Date: August 31, 2023 Amended Date: October 30, 2023 Effective Date: June 3

CONSENT OF QUALIFIED PERSON

Exhibit 23.21 CONSENT OF QUALIFIED PERSON WSP Canada Inc., in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary James B

CONSENT OF QUALIFIED THIRD PARTY FIRM

Exhibit 23.11 CONSENT OF QUALIFIED THIRD PARTY FIRM Mining Plus Pty Ltd, in connection with Allkem Livent plc’s registration statement on Form S4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Su

As filed with the Securities and Exchange Commission on September 26, 2023

TABLE OF CONTENTS As filed with the Securities and Exchange Commission on September 26, 2023 Registration No.

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.9 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “R

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.14 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “

SEC Technical Report Summary Olaroz Lithium Facility Prepared by: Hydrominex Geoscience 63 Carlotta St, Greenwich, NSW, 2065, Australia Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia Prepared for: Allkem Limited Riparian Plaza—Level 35 71

Exhibit 96.2 SEC Technical Report Summary Olaroz Lithium Facility Prepared by: Hydrominex Geoscience 63 Carlotta St, Greenwich, NSW, 2065, Australia and Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000, Australia Report Date: August 31, 2023 Effective Date: June 30, 2023 1 Olaroz Lithium Facili

Exhibit 23.16 CONSENT OF QUALIFIED PERSON

Exhibit 23.16 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Sal de

CONSENT OF QUALIFIED PERSON

Exhibit 23.12 CONSENT OF QUALIFIED PERSON Albert Thamm, F.Aus.IMM in connection with Allkem Livent PLC’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary,

Exhibit 23.14 CONSENT OF QUALIFIED PERSON

Exhibit 23.14 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Olaroz

CONSENT OF QUALIFIED PERSON

Exhibit 23.7 CONSENT OF QUALIFIED PERSON DRA Americas Inc. (“DRA”), in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consents to: • the use in connection with the Registration Statement of the technical report titled “Technical Report on the W

As filed with the Securities and Exchange Commission on September 26, 2023

As filed with the Securities and Exchange Commission on September 26, 2023 Registration No.

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.7 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “R

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.13 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “

SEC Technical Report Summary Sal de Vida Lithium Brine Project Prepared by: Montgomery & Associates Consultores Limitada 1550 East Prince Road, Tucson, Arizona 85719 United States of America Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia

Exhibit 96.3 SEC Technical Report Summary Sal de Vida Lithium Brine Project Prepared by: Montgomery & Associates Consultores Limitada 1550 East Prince Road, Tucson, Arizona 85719 United States of America and Gunn Metallurgy 58 Deerhurst Rd, Brookfield 4069 Australia Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000, Australia Report Date: August 31, 202

CONSENT OF QUALIFIED PERSON

Exhibit 23.20 CONSENT OF QUALIFIED PERSON QV1- Level 3, 250 St Georges Tce, Perth Western Australia 6000 PO Box 7085, Cloisters Square Western Australia 6850 T / +61 (0)8 9204 0700 Dear Sir/Madam: RE: SEC TECHNICAL REPORT SUMMARY, JAMES BAY LITHIUM PROJECT Wave International Pty Ltd. in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus includ

CONSENT OF QUALIFIED PERSON

Exhibit 23.15 CONSENT OF QUALIFIED PERSON Montgomery & Associates Consultores Limitada, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Tec

Exhibit 23.14 CONSENT OF QUALIFIED PERSON

Exhibit 23.14 CONSENT OF QUALIFIED PERSON Gunn Metallurgy, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Olaroz

Exhibit 23.13 CONSENT OF QUALIFIED PERSON

Exhibit 23.13 CONSENT OF QUALIFIED PERSON Hydrominex Geoscience, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary,

Mining Lease 74/244, granted as of December 24, 2009, of Galaxy Lithium Australia Pty Ltd. (Exhibit 10.9 to Amendment No. 1 to the Registrant's Registration Statement on Form S-4/A, filed on September 27, 2023)

Exhibit 10.9 MINING TENEMENT DETAILS REPORT DISCLAIMER: This is not the official Register referred to in Reg. 84C of the Mining Regulations 1981. MINING LEASE 74/244 Tenement Summary Identifier : M 74/244 District : PHILLIPS RIVER M.F. Current Area : 1,830.00000 HA Status : Live Mark Out : 04/08/2009 11:55:00 Received : 07/08/2009 15:59:00 Term Granted : 21 Years Lodging Office : PERTH Commence :

Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON

Exhibit 23.10 Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Marc Rougier, state that I am responsible for preparing or supervising the preparation of parts of the technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with a report date of 8 September, 2023 as signed and certif

CONSENT OF QUALIFIED THIRD PARTY FIRM

Exhibit 23.11 CONSENT OF QUALIFIED THIRD PARTY FIRM Mining Plus Pty Ltd., in connection with Allkem Livent plc’s registration statement on Form S4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report S

CONSENT OF QUALIFIED PERSON

Exhibit 23.7 CONSENT OF QUALIFIED PERSON DRA Americas Inc. (“DRA”), in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consents to: • the use in connection with the Registration Statement of the technical report titled “Technical Report on the W

Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON

Exhibit 23.9 Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Carl Pednault, state that I am responsible for preparing or supervising the preparation of parts of the technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with a report date of 8 September, 2023 as signed and certifi

CONSENT OF QUALIFIED PERSON

Exhibit 23.12 CONSENT OF QUALIFIED PERSON Albert Thamm, F.Aus.IMM in connection with Allkem Livent PLC’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary,

Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON

Exhibit 23.10 Marc Rougier, ing. Principal Geotechnical Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Marc Rougier, state that I am responsible for preparing or supervising the preparation of parts of the technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with a report date of 8 September, 2023 as signed and certif

Exhibit 23.17 CONSENT OF QUALIFIED PERSON

Exhibit 23.17 CONSENT OF QUALIFIED PERSON Marek Dworzanowski, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Cau

CONSENT OF QUALIFIED PERSON

Exhibit 23.18 CONSENT OF QUALIFIED PERSON Frederik Reidel, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Caucha

CONSENT OF QUALIFIED PERSON

Exhibit 23.20 CONSENT OF QUALIFIED PERSON QV1- Level 3, 250 St Georges Tce, Perth Western Australia 6000 PO Box 7085, Cloisters Square Western Australia 6850 T / +61 (0)8 9204 0700 Dear Sir/Madam: RE: SEC TECHNICAL REPORT SUMMARY, JAMES BAY LITHIUM PROJECT Wave International Pty Ltd. in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus includ

SEC Technical Report Summary Cauchari Lithium Brine Project Prepared by: Marek Dworzanowski Metallurgical Engineer Frederik Reidel Managing Director, Atacama Water SpA Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Que

Exhibit 96.4 SEC Technical Report Summary Cauchari Lithium Brine Project Prepared by: Marek Dworzanowski Metallurgical Engineer and Frederik Reidel Managing Director, Atacama Water SpA Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000,Australia Report Date: August 31, 2023 Effective Date: June 30, 2023 Cauchari Lithium Brine Project SEC Technical Report

SEC Technical Report Summary Allkem Limited James Bay Lithium Project Prepared by:

Exhibit 96.5 SEC Technical Report Summary Allkem Limited James Bay Lithium Project Prepared by: SLR Consulting (Canada) Ltd. 55 University Ave., Suite 501 Toronto, ON M5J 2H7 Wave International Pty Ltd. QV1-Level 3, 250 St Georges Tce Perth, WA 6000 and WSP Canada Inc. 1600, Boulevard René-Lévesque, 11 étage Montréal, QC H3H 1P9 Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street

CONSENT OF GORDON DYAL & CO., LLC

Exhibit 99.3 CONSENT OF GORDON DYAL & CO., LLC We hereby consent to the inclusion in the registration statement on Form S-4 of Allkem Livent plc (the “Registration Statement”) and in the proxy statement/prospectus included therein (the “Proxy Statement/Prospectus”), which forms part of the Registration Statement, of our written opinion, dated May 10, 2023, to the board of directors of Livent Corpo

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.8 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “R

Exhibit 23.13 CONSENT OF QUALIFIED PERSON

Exhibit 23.13 CONSENT OF QUALIFIED PERSON Hydrominex Geoscience, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary,

CONSENT OF QUALIFIED PERSON

Exhibit 23.18 CONSENT OF QUALIFIED PERSON Frederik Reidel, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Caucha

Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON

Exhibit 23.9 Carl Pednault, ing. Principal Mine Waste Engineer WSP Canada Inc. CONSENT OF QUALIFIED PERSON I, Carl Pednault, state that I am responsible for preparing or supervising the preparation of parts of the technical report summary titled “SEC Technical Report Summary, Pre-Feasibility Study on the Whabouchi Mine, Nemaska, Quebec” with a report date of 8 September, 2023 as signed and certifi

Technical Report Summary on Mt Cattlin Lithium Project, prepared by Mining Plus Pty Ltd. and Albert Thamm, F.Aus.IMM, dated August 31, 2023 and amended October 30, 2023 (Exhibit 96.1 to Amendment No. 3 to the Registrant’s Registration Statement on Form S-4/A, filed on October 30, 2023)

Exhibit 96.1 SEC Technical Report Summary Mt. Cattlin Lithium Project SEC Technical Report Summary Mt Cattlin Lithium Project Prepared by: Mining Plus Pty Ltd. Bravo Building, 1 George Wienke Drive, Perth Domestic Airport, WA 6105 and Albert Thamm, F.Aus.IMM of Allkem Limited Prepared for: Allkem Limited Riparian Plaza—Level 35 71 Eagle Street Brisbane, Queensland 4000, Australia Report Date: Augu

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.12 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “

CONSENT OF QUALIFIED PERSON

Exhibit 23.8 CONSENT OF QUALIFIED PERSON SGS Geological Services (“SGS”), in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consents to: • the use in connection with the Registration Statement of the technical report titled “Technical Report on

Exhibit 23.17 CONSENT OF QUALIFIED PERSON

Exhibit 23.17 CONSENT OF QUALIFIED PERSON Marek Dworzanowski, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary, Cau

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.15 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “

CONSENT OF QUALIFIED PERSON

Exhibit 23.15 CONSENT OF QUALIFIED PERSON Montgomery & Associates Consultores Limitada, in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Tec

Consent of Qualified Person

Exhibit 23.19 SLR Consulting (Canada) Ltd. 55 University Ave., Suite 501, Toronto, ON M5J 2H7 September 26, 2023 Consent of Qualified Person SLR Consulting (Canada) Ltd. (“SLR”), in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Stat

CONSENT OF QUALIFIED PERSON

Exhibit 23.21 CONSENT OF QUALIFIED PERSON WSP Canada Inc., in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Statement”), consents to: 1. The filing and use of the technical report summary titled “SEC Technical Report Summary James B

CONSENT OF QUALIFIED PERSON

Exhibit 23.8 CONSENT OF QUALIFIED PERSON SGS Geological Services (“SGS”), in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein, including any amendments thereto (collectively, the “Registration Statement”), consents to: • the use in connection with the Registration Statement of the technical report titled “Technical Report on

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.6 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “R

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.11 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “

CONSENT OF PROSPECTIVE DIRECTOR

Exhibit 99.10 CONSENT OF PROSPECTIVE DIRECTOR In accordance with Rule 438 promulgated under the Securities Act of 1933, as amended, I hereby consent to my being named in the Registration Statement on Form S-4, to which this consent is an exhibit, filed by Allkem Livent plc (“NewCo”) with the Securities and Exchange Commission, and all amendments (including post-effective amendments) thereto (the “

Consent of Qualified Person

Exhibit 23.19 SLR Consulting (Canada) Ltd. 55 University Ave., Suite 501, Toronto, ON M5J 2H7 September 26, 2023 Consent of Qualified Person SLR Consulting (Canada) Ltd. (“SLR”), in connection with Allkem Livent plc’s registration statement on Form S-4 and the proxy statement/prospectus included therein and any amendments or supplements and/or exhibits thereto (collectively, the “Registration Stat