Alkermes plc. — Director's Dealing 2012

Nov 19, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Alkermes plc. (ALKS)
CIK: 0001520262
Period of Report: 2012-11-18

Reporting Person: Peterson Rebecca (SVP, Corporate Communications)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-11-18	Ordinary Shares	M	1875	—	Acquired	1875	Direct
2012-11-18	Ordinary Shares	F	595	$19.49	Disposed	1280	Direct
2012-11-19	Ordinary Shares	M	3750	$9.21	Acquired	5030	Direct
2012-11-19	Ordinary Shares	S	3750	$19.5771	Disposed	1280	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-11-18	Restricted Stock Unit Award	$0	M	1875	Disposed		Ordinary Shares (1875)	Direct
2012-11-19	Employee Stock Option (Right to Buy)	$9.21	M	3750	Disposed	2019-11-18	Ordinary Shares (3750)	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: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $19.47 to $19.70. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request

F4: Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 11/18/10.

F5: Vests in 4 equal annual installments commencing on 11/18/10.