FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person *   Gaffin David Joseph 2. Date of Event Requiring Statement (Month/Day/Year) 05/26/2016 3. Issuer Name and Ticker or Trading Symbol Alkermes plc. [ALKS] (Last) (First) (Middle) 852 WINTER STREET 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) SVP, CLO, Alkermes, Inc. 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) WALTHAM, MA 02451 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Ordinary Shares 19,590 D Â

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Option (Right to Buy)	  (1)	12/12/2016	Ordinary Shares	5,000	$ 14.38	D	Â
Employee Stock Option (Right to Buy)	  (1)	06/01/2017	Ordinary Shares	4,500	$ 15.95	D	Â
Employee Stock Option (Right to Buy)	  (1)	11/05/2017	Ordinary Shares	500	$ 14.13	D	Â
Employee Stock Option (Right to Buy)	  (1)	05/27/2018	Ordinary Shares	1,100	$ 12.29	D	Â
Employee Stock Option (Right to Buy)	  (1)	05/26/2019	Ordinary Shares	7,000	$ 8.55	D	Â
Employee Stock Option (Right to Buy)	  (1)	05/17/2020	Ordinary Shares	3,000	$ 11.74	D	Â
Employee Stock Option (Right to Buy)	  (1)	05/20/2021	Ordinary Shares	2,250	$ 18.105	D	Â
Employee Stock Option (Right to Buy)	  (1)	05/21/2022	Ordinary Shares	41,000	$ 16.55	D	Â
Employee Stock Option (Right to Buy)	05/28/2014(2)	05/28/2023	Ordinary Shares	30,000	$ 33.72	D	Â
Restricted Stock Unit Award	05/28/2014(3)	  (3)	Ordinary Shares	2,500	$ 0	D	Â
Employee Stock Option (Right to Buy)	03/03/2015(4)	03/03/2024	Ordinary Shares	25,000	$ 47.16	D	Â
Restricted Stock Unit Award	03/03/2015(5)	  (5)	Ordinary Shares	2,500	$ 0	D	Â
Employee Stock Option (Right to Buy)	02/26/2016(6)	02/26/2025	Ordinary Shares	17,750	$ 71.23	D	Â
Restricted Stock Unit Award	02/26/2016(7)	  (7)	Ordinary Shares	3,300	$ 0	D	Â
Performance Restricted Stock Units	  (8)	  (8)	Ordinary Shares	1,600	$ (9)	D	Â
Employee Stock Option (Right to Buy)	03/01/2017(10)	02/28/2026	Ordinary Shares	36,000	$ 32.27	D	Â
Restricted Stock Unit Award	03/01/2017(11)	  (11)	Ordinary Shares	9,000	$ 0	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Gaffin David Joseph 852 WINTER STREET WALTHAM, MA 02451	Â	Â	  SVP, CLO, Alkermes, Inc.	Â

Signatures

/s/ Jennifer Baptiste, attorney-in-fact for David J Gaffin		06/01/2016
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	These options are fully vested in accordance with their terms.
(2)	Shares subject to the stock option award vest in four equal annual installments commencing on 5/28/14.
(3)	Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 5/28/14.
(4)	Shares subject to the stock option award vest in four equal annual installments commencing on 3/3/15.
(5)	Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 3/3/2015.
(6)	Shares subject to the stock option award vest in four equal annual installments commencing on 2/26/2016.
(7)	Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 2/26/2016.
(8)	Represents the earned but unvested portion of the performance restricted stock units granted to the reporting person on March 3, 2014. The remaining fifty percent of the earned performance restricted stock units will vest on October 5, 2016.
(9)	Each performance restricted stock unit represents a contingent right to receive one ordinary share of Alkermes plc.
(10)	Shares subject to the stock option award vest in four equal annual installments commencing on 3/1/2017.
(11)	Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 3/1/2017.

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