Gilberto Antoniazzi - Mar 6, 2025 Form 4 Insider Report for Arcadium Lithium plc (ALTM)

Role: CFO, VP & Treasurer
Signature: /s/ Sara Ponessa, as attorney-in-fact
Stock symbol: ALTM
Transactions as of: Mar 6, 2025
Transactions value $: $0
Form type: 4
Date filed: 3/6/2025, 06:29 PM
Previous filing: Feb 14, 2025
SEC: View on sec.gov

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	ALTM	Ordinary Shares	Disposed to Issuer		-24.8K	-100%		0	Mar 6, 2025	Direct	F1
transaction	ALTM	Ordinary Shares	Disposed to Issuer		-258K	-100%		0	Mar 6, 2025	Direct	F2

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

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	ALTM	Stock Option (Right to Buy)	Disposed to Issuer		-259K	-100%		0	Mar 6, 2025	Ordinary Shares	259K	$4.95	Direct	F3
transaction	ALTM	Stock Option (Right to Buy)	Disposed to Issuer		-41.7K	-100%		0	Mar 6, 2025	Ordinary Shares	41.7K	$3.45	Direct	F3
transaction	ALTM	Stock Option (Right to Buy)	Disposed to Issuer		-24.8K	-100%		0	Mar 6, 2025	Ordinary Shares	24.8K	$5.10	Direct	F3
transaction	ALTM	Stock Option (Right to Buy)	Disposed to Issuer		-103K	-100%		0	Mar 6, 2025	Ordinary Shares	103K	$7.07	Direct	F3
transaction	ALTM	Stock Option (Right to Buy)	Disposed to Issuer		-103K	-100%		0	Mar 6, 2025	Ordinary Shares	103K	$7.07	Direct	F3
transaction	ALTM	Stock Option (Right to Buy)	Disposed to Issuer		-35.9K	-100%		0	Mar 6, 2025	Ordinary Shares	35.9K	$9.70	Direct	F3
transaction	ALTM	Stock Option (Right to Buy)	Disposed to Issuer		-38.6K	-100%		0	Mar 6, 2025	Ordinary Shares	38.6K	$8.74	Direct	F3
transaction	ALTM	Stock Option (Right to Buy)	Disposed to Issuer		-128K	-100%		0	Mar 6, 2025	Ordinary Shares	128K	$8.46	Direct	F3

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

Gilberto Antoniazzi is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may continue.

Explanation of Responses:

Id	Content
F1	Represents shares of common stock of Aracdium Lithium plc ("Arcadium") disposed of pursuant to the Transaction Agreement, dated October 9, 2024, by and among Arcadium, Rio Tinto Western Holdings Limited ("Parent") and Rio Tinto BM Subsidiary Limited ("Buyers") (the "Transaction Agreement"). Pursuant to the Transaction Agreement, at the effective time of the transaction contemplated thereby (the "Effective Time"), each share of Arcadium common stock held by the reporting person was converted automatically into the right to receive $5.85 per share in cash (the "Consideration").
F2	Pursuant to the Transaction Agreement, at the Effective Time, each Arcadium restricted stock units ("Arcadium RSU") held by the reporting person and granted under the Arcadium Omnibus Incentive Plan was canceled in exchange for restricted stock units with respect to a number of ordinary shares of either Rio Tinto plc or Rio Tinto Limited ("Listed Shares") of equivalent value and with the same terms and conditions as applied to such Arcadium RSU immediately prior to the Effective Time ("Rio Tinto RSUs"). The number of Listed Shares subject to such Rio Tinto RSUs equals one multiplied by an exchange ratio of 0.0920493627351811, which equals the quotient obtained by dividing (i) the Consideration by (ii) the average volume weighted average price per ordinary share of the applicable Listed Share for the 30 consecutive trading day period ending on the last trading day preceding the Effective Time (the "Equity Award Conversion Ratio").
F3	Pursuant to the Transaction Agreement, at the Effective Time, each award of Arcadium stock options ("Arcadium Options") held by the reporting person and granted under the Arcadium Omnibus Incentive Plan was canceled in exchange for an award of stock options with respect to a number of Listed Shares of equivalent value and with the same terms and conditions as applied to such stock options immediately prior to the Effective Time ("Rio Tinto Options"). The number of Listed Shares subject to each such Rio Tinto Options equals the number of shares of Arcadium common stock subject to the corresponding Arcadium Options immediately prior to the Effective Time multiplied by the Equity Award Conversion Ratio. The exercise price of each such Rio Tinto Option equals the exercise price of the corresponding Arcadium Options divided by the Equity Award Conversion Ratio.