FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN 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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1. Name and Address of Reporting Person * Peterson Rebecca   2. Issuer Name and Ticker or Trading Symbol Alkermes plc. [ALKS] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) SVP, Corporate Communications (Last) (First) (Middle) 852 WINTER ST. 3. Date of Earliest Transaction (Month/Day/Year) 05/20/2014 (Street) WALTHAM, MA 02451 4. If Amendment, Date Original Filed(Month/Day/Year) 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 Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Ordinary Shares 05/20/2014   M   2,000 A $ 0 2,000 D   Ordinary Shares 05/20/2014   F   943 D $ 43.98 1,057 D   Ordinary Shares 05/21/2014   M(1)   18,750 A $ 16.55 19,807 D   Ordinary Shares 05/21/2014   S(2)   18,450 D $ 44.0003 (3) 1,357 D   Ordinary Shares 05/21/2014   S(2)   300 D $ 44.6483 (4) 1,057 D   Ordinary Shares 05/21/2014   M   2,500 A $ 0 3,557 D   Ordinary Shares 05/21/2014   F   1,179 D $ 44.48 2,378 D   Ordinary Shares 05/22/2014   S(2)   1,057 D $ 44.17 1,321 D

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

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Restricted Stock Unit Award

$ 0

05/20/2014

M

2,000

05/20/2012(5)

(5)

Ordinary Shares

2,000

$ 0

2,000

D

Employee Stock Option (Right to Buy)

$ 16.55

05/21/2014

M(1)

18,750

05/21/2013(6)

05/21/2022

Ordinary Shares

18,750

$ 0

37,500

D

Restricted Stock Unit Award

$ 0

05/21/2014

M

2,500

05/21/2013(7)

(7)

Ordinary Shares

2,500

$ 0

5,000

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Peterson Rebecca 852 WINTER ST. WALTHAM, MA 02451			SVP, Corporate Communications

Signatures

/s/ Jennifer Baptiste, attorney-in-fact for Rebecca Peterson		05/22/2014
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(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)	This option exercise was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person.
(2)	This sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person.
(3)	The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $43.62 to $44.55. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.
(4)	The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $44.635 to $44.66. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.
(5)	Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 5/20/12.
(6)	Vests in 4 equal annual installments commencing on 5/21/13.
(7)	Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 5/21/13.

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