Alkermes plc. — Director's Dealing 2017

May 19, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Alkermes plc. (ALKS)
CIK: 0001520262
Period of Report: 2017-05-18

Reporting Person: LANDINE MICHAEL J (SVP, Corp Dev., Alkermes, Inc.)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-05-18	Ordinary Shares	M	5000	$15.95	Acquired	167370	Direct
2017-05-18	Ordinary Shares	M	5000	$15.95	Acquired	172370	Direct
2017-05-18	Ordinary Shares	S	8700	$57.1378	Disposed	163670	Direct
2017-05-18	Ordinary Shares	S	1300	$57.8119	Disposed	162370	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-05-18	Non Qualified Stock Option (Right to Buy)	$15.95	M	5000	Disposed	2017-06-01	Ordinary Shares (5000)	Direct
2017-05-18	Incentive Stock Option (Right to Buy)	$15.95	M	5000	Disposed	2017-06-01	Ordinary Shares (5000)	Direct

Footnotes

F1: This option exercise was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 11/6/15.

F2: This sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 11/6/15.

F3: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $56.75 to $57.74. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

F4: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $57.745 to $57.85. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

F5: These options are fully vested in accordance with their terms.