AMARIN CORP PLC\UK — Director's Dealing 2021

Apr 30, 2021

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AMARIN CORP PLC\UK (AMRN)
CIK: 0000897448
Period of Report: 2021-04-30

Reporting Person: Ketchum Steven B (N/A)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2021-04-30	Ordinary Shares	M	1528.00	—	Acquired	441758.00	Direct
2021-04-30	Ordinary Shares	M	1528.00	—	Acquired	443286.00	Direct
2021-04-30	Ordinary Shares	M	3056.00	—	Acquired	446342.00	Direct
2021-04-30	Ordinary Shares	F	3128.00	$5.24	Disposed	443214.00	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2021-04-30	Restricted Stock Units	$0.00	M	1528.00	Disposed		Ordinary Shares (1528.00)	Direct
2021-04-30	Restricted Stock Units	$0.00	M	1528.00	Disposed		Ordinary Shares (1528.00)	Direct
2021-04-30	Restricted Stock Units	$0.00	M	3056.00	Disposed		Ordinary Shares (3056.00)	Direct

Footnotes

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

F2: As previously reported on February 27, 2020 and March 1, 2021, on May 15, 2017, the Reporting Person was granted 220,000 Restricted Stock Units ("RSUs") under the Amarin Corporation plc 2011 Stock Incentive Plan, of which the performance criteria related to two tranches representing 25% of the total award each was deemed achieved on February 25, 2020 pursuant to reporting of audited net product revenues for 2019 exceeding $400 million and of which the performance criteria related to one tranche representing 50% of the total award was deemed achieved on February 25, 2021 pursuant to reporting of audited net product revenues for 2020 exceeding $500 million. The tranches vest ratably over 36 months beginning September 30, 2018 subject to achievement of the performance criteria and continued service of the Reporting Person as provided in the RSU Award Agreement between the Issuer and Reporting Person. The thirty-second vesting event occurred on April 30, 2021.

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

F6: Each RSU represents a contingent right to receive one Ordinary Share or cash in lieu thereof at the Issuer's discretion.