Alkermes plc. — Director's Dealing 2016

May 5, 2016

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Alkermes plc. (ALKS)
CIK: 0001520262
Period of Report: 2016-05-04

Reporting Person: MITCHELL PAUL J (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2016-05-04	Ordinary Shares	M	2000	$18.29	Acquired	10000	Direct
2016-05-04	Ordinary Shares	S	2000	$38.60	Disposed	8000	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2016-05-04	Non Qualified Stock Option (Right to Buy)	$18.29	M	2000	Disposed	2017-10-09	Ordinary Shares (2000)	Direct

Footnotes

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

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

F3: These options are fully vested in accordance with their terms.