AMARIN CORP PLC\UK — Director's Dealing 2011

Apr 20, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: AMARIN CORP PLC\UK (AMRN)
CIK: 0000897448
Period of Report: 2011-04-18

Reporting Person: Zakrzewski Joseph S (Director, Chief Executive Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-04-18	Ordinary Shares	M	100000	$1.35	Acquired	163604	Direct
2011-04-18	Ordinary Shares	M	200000	$3.40	Acquired	363604	Direct
2011-04-18	Ordinary Shares	S	300000	$15.7607	Disposed	63604	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-04-18	Stock Option (right to buy)	$1.35	M	100000	Disposed	2019-12-21	Ordinary Shares (100000)	Direct
2011-04-18	Stock Option (right to buy)	$3.40	M	200000	Disposed	2020-11-11	Ordinary Shares (200000)	Direct

Footnotes

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

F2: On December 21, 2009, the reporting person was granted an option to purchase 1,170,000 ordinary shares under the Amarin Corporation plc 2002 Stock Option Plan. The stock option initally vested in four equal annual installments beginning on January 1, 2010. In December 2010, the Issuer's Board of Directors approved the acceleration of the vesting of this award by six months such that the option vests in four equal installments and will be fully vested on July 1, 2013.

F3: On November 11, 2010, the reporting person was granted an option to purchase 1,750,000 ordinary shares under the Amarin Corporation plc 2002 Stock Option Plan. The stock option vests in four equal annual installments beginning on November 11, 2010.

F4: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $15.55 to $16.12, 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: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person.