AMARIN CORP PLC\UK — Director's Dealing 2012

Jul 30, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AMARIN CORP PLC\UK (AMRN)
CIK: 0000897448
Period of Report: 2012-07-26

Reporting Person: SEDLACK STUART D (Senior Vice President)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-07-26	Ordinary Shares	A	6950	—	Acquired	6950	Direct
2012-07-27	Ordinary Shares	S	541	$14.74	Disposed	6409	Direct
2012-07-27	Ordinary Shares	S	6409	$13.78	Disposed	0	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-07-26	Restricted Stock Units	$0	A	6950	Acquired		Ordinary Shares (6950)	Direct

Footnotes

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

F2: On February 1, 2012, the Reporting Person was granted 41,700 restricted stock units (the "RSUs") under the Amarin Corporation plc 2011 Stock Incentive Plan. Each RSU represents a contingent right to receive one Ordinary Share or cash in lieu thereof at the Issuer's discretion. The RSUs vest in six equal installments based on the Issuer's satisfaction of certain performance criteria and continued employment of the Reporting Person as provided in the Restricted Stock Unit Award Agreement between the Issuer and the Reporting Person. The performance criteria for the first installment was met, resulting in vesting of 6,950 RSUs.

F3: These RSUs vest on July 26, 2013, subject to continued employment of the Reporting Person through such date. Ordinary Shares will be delivered to the Reporting Person as soon as practicable after the vesting date.

F4: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 4, 2012.

F5: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $15.32 to $14.34, 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.

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

F7: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $14.32 to $13.50, inclusive.