AMARIN CORP PLC\UK — Director's Dealing 2023

Feb 23, 2023

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AMARIN CORP PLC\UK (AMRN)
CIK: 0000897448
Period of Report: 2023-01-31

Reporting Person: Ketchum Steven B (Chief Scientific Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2023-01-31	Ordinary Shares	M	34567	—	Acquired	578588	Direct
2023-01-31	Ordinary Shares	F	13706	$1.86	Disposed	564882	Direct
2023-02-21	Ordinary Shares	A	29134	—	Disposed	594016	Direct
2023-02-21	Ordinary Shares	F	14520	$1.80	Disposed	579496	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2023-01-31	Restricted Stock Units	$0.00	M	34567	Disposed		Ordinary Shares (34567)	Direct
2023-02-21	Stock Option (Right to Buy)	$1.80	A	269600	Acquired	2033-02-21	Ordinary Shares (269600)	Direct
2023-02-21	Restricted Stock Units	$0.00	A	134800	Acquired		Ordinary Shares (134800)	Direct
2023-02-21	Restricted Stock Units	$0.00	A	14567	Acquired		Ordinary Shares (14567)	Direct

Footnotes

F1: The Ordinary Shares may be represented by American Depositary Shares, each of which currently represents one Ordinary Share.

F2: On February 4, 2022, the Reporting Person was granted 103,700 Restricted Stock Units ("RSUs") under the Amarin Corporation plc 2020 Stock Incentive Plan (as amended, the "Plan"). These RSUs vest in three equal installments on each of January 31, 2023, January 31, 2024 and January 31, 2025.

F3: Not applicable.

F4: Represents withholding by the Issuer of shares in respect of tax liability incident to the vesting of a security issued in accordance with Rule 16b-3, and not a market sale of securities.

F5: On January 4, 2021 (the "Grant Date"), the Reporting Person was granted RSUs under the Plan, which only vest subject to the achievement of certain performance-based milestones disclosed in the Issuer's definitive proxy statement filed with the U.S. Securities and Exchange Commission on May 24, 2022 and subject to the Reporting Person's continued service with the Issuer as provided in the RSU Award Agreement between the Issuer and Reporting Person. This RSU Award also provides that if performance metrics are achieved prior to the 3rd anniversary of the Grant Date, the achieved portion of such RSU Award shall also be subject to time-based vesting such that 1/3 of such amount shall become vested on each of the first, second and third anniversary of the Grant Date, subject to the Reporting Person's continued service to the Issuer.

F6: (Continued from Footnote 5) The Issuer's Remuneration Committee of its Board certified the achievement of performance effective as of February 21, 2023, resulting in the vesting of 29,134 RSUs (two tranches) and the remaining 14,567 (third tranche) scheduled to vest on January 4, 2024.

F7: Please see the section titled "Remarks" below for additional information.

F8: Each RSU represents a contingent right to receive one Ordinary Share or cash in lieu thereof at the Issuer's discretion.

F9: On February 21, 2023, the Reporting Person was granted an option to purchase 269,600 Ordinary Shares under the Plan. The shares subject to this option shall vest and become exercisable over four years, with 25% to vest on the first anniversary of the grant date and the balance to vest ratably over the subsequent 12 calendar quarters on the last day of each April, July, October and January.

F10: On February 21, 2023, the Reporting Person was granted 134,800 RSUs under the Plan. These RSUs vest in three equal installments on each of January 31, 2024, January 31, 2025 and January 31, 2026.