AMARIN CORP PLC\UK — Director's Dealing 2019

Feb 1, 2019

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AMARIN CORP PLC\UK (AMRN)
CIK: 0000897448
Period of Report: 2019-01-31

Reporting Person: Ketchum Steven B (Chief Scientific Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2019-01-31	Ordinary Shares	M	2604	$1.40	Acquired	343901	Direct
2019-01-31	Ordinary Shares	M	4167	$2.50	Acquired	348068	Direct
2019-01-31	Ordinary Shares	M	2770	$2.95	Acquired	350838	Direct
2019-01-31	Ordinary Shares	S	9541	$17.4903	Disposed	341297	Direct
2019-01-31	Ordinary Shares	M	26666	—	Acquired	367963	Direct
2019-01-31	Ordinary Shares	M	29000	—	Acquired	396963	Direct
2019-01-31	Ordinary Shares	M	26000	—	Acquired	422963	Direct
2019-01-31	Ordinary Shares	F	40482	$16.94	Disposed	382481	Direct
2019-02-01	Ordinary Shares	S	27989	$17.0602	Disposed	354492	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2019-01-31	Stock Option (Right to Buy)	$1.40	M	2604	Disposed	2026-01-31	Ordinary Shares (2604)	Direct
2019-01-31	Stock Option (Right to Buy)	$2.50	M	4167	Disposed	2025-07-06	Ordinary Shares (4167)	Direct
2019-01-31	Stock Option (Right to Buy)	$2.95	M	2770	Disposed	2027-01-31	Ordinary Shares (2770)	Direct
2019-01-31	Restricted Stock Units	$0.00	M	26666	Disposed		Ordinary Shares (26666)	Direct
2019-01-31	Restricted Stock Units	$0.00	M	29000	Disposed		Ordinary Shares (29000)	Direct
2019-01-31	Restricted Stock Units	$0.00	M	26000	Disposed		Ordinary Shares (26000)	Direct
2019-02-01	Restricted Stock Units	$0.00	A	38200	Acquired		Ordinary Shares (38200)	Direct
2019-02-01	Stock Option (Right to Buy)	$16.88	A	53500	Acquired	2029-02-01	Ordinary Shares (53500)	Direct

Footnotes

F1: Multiple reportable transactions are reported in the Form 4 including grants of options, grants of restricted stock units, exercise of previously granted options, vesting of previously granted restricted stock units and sale of certain shares. The market sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan previously adopted by the Reporting Person.

F2: The Ordinary Shares may be represented by American Depositary Shares, each of which currently represents one Ordinary Share.

F3: Please see the section titled "Remarks" below for additional information.

F4: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $17.09 to $17.90, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

F5: On February 1, 2016, the Reporting Person was granted 80,000 Restricted Stock Units ("RSUs") under the Amarin Corporation plc 2011 Stock Incentive Plan (the "Plan"). These RSUs vest in three equal installments on each of January 31, 2017, January 31, 2018 and January 31, 2019. The third and final vesting event occurred on January 31, 2019.

F6: Not applicable.

F7: On February 1, 2017, the Reporting Person was granted 87,000 RSUs under the Plan. These RSUs vest in three equal installments on each of January 31, 2018, January 31, 2019 and January 31, 2020. The second vesting event occurred on January 31, 2019.

F8: On February 1, 2018, the Reporting Person was granted 78,000 RSUs under the Plan. These RSUs vest in three equal installments on each of January 31, 2019, January 31, 2020 and January 31, 2021. The first vesting event occurred on January 31, 2019.

F9: 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.

F10: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $16.81 to $17.62, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range.

F11: On February 1, 2016, the Reporting Person was granted an option to purchase 125,000 Ordinary Shares under the Plan. The shares subject to this option shall vest and become exercisable in 48 equal monthly installments on the last day of each month that began on February 29, 2016.

F12: On July 6, 2015, the Reporting Person was granted an option to purchase 200,000 Ordinary Shares under the Plan. The shares subject to this option shall vest and become exercisable in 48 equal monthly installments on the last day of each month that began on July 31, 2015.

F13: On February 1, 2017, the Reporting Person was granted an option to purchase 133,000 Ordinary Shares under the Plan. The shares subject to this option shall vest and become exercisable in 48 equal monthly installments on the last day of each month that began on February 28, 2017.

F14: Each RSU represents a contingent right to receive one Ordinary Share or cash in lieu thereof at the Issuer's discretion.

F15: On February 1, 2019, the Reporting Person was granted 38,200 RSUs under the Plan. These RSUs vest in three equal installments on each of January 31, 2020, January 31, 2021 and January 31, 2022.

F16: On February 1, 2019, the Reporting Person was granted an option to purchase 53,500 Ordinary Shares under the Plan. The shares subject to this option shall vest and become exercisable in 16 equal quarterly installments starting on May 15, 2019.