Alkermes plc. — Director's Dealing 2018

May 3, 2018

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Alkermes plc. (ALKS)
CIK: 0001520262
Period of Report: 2018-05-01

Reporting Person: POPS RICHARD F (Director, Director and CEO, Alkermes plc)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2018-05-01	Ordinary Shares	M	50000	$12.29	Acquired	716352	Direct
2018-05-01	Ordinary Shares	S	49100	$44.0116	Disposed	667252	Direct
2018-05-01	Ordinary Shares	S	900	$44.6633	Disposed	666352	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2018-05-01	Employee Stock Option (Right to Buy)	$12.29	M	50000	Disposed	2018-05-27	Ordinary Shares (50000)	Direct

Footnotes

F1: This option exercise was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 3/6/18.

F2: This sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 3/6/18.

F3: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $43.52 to $44.51. 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 $44.53 to $44.80. 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.