Ownership Submission
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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(Print or Type Responses)
1. Name and Address of Reporting Person *
MITCHELL PAUL J
  2. Issuer Name and Ticker or Trading Symbol
Alkermes plc. [ALKS]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
CONNAUGHT HOUSE, 1 BURLINGTON ROAD
3. Date of Earliest Transaction (Month/Day/Year)
05/01/2018
(Street)

DUBLIN 4 IRELAND 
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 05/01/2018   M(1)   1,000 A $ 8.98 1,000 I The Paul J. Mitchell Trust (2)
Ordinary Shares 05/01/2018   S(3)   1,000 D $ 44.32 0 I The Paul J. Mitchell Trust (2)
Ordinary Shares               8,000 D  

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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
Non Qualified Stock Option (Right to Buy) $ 8.98 05/01/2018   M(1)     1,000   (4) 10/06/2019 Ordinary Shares 1,000 $ 0 18,000 I The Paul J. Mitchell Trust (2) (5)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MITCHELL PAUL J
CONNAUGHT HOUSE
1 BURLINGTON ROAD
DUBLIN 4 IRELAND 
  X      

Signatures

 /s/ Jennifer Baptiste, attorney-in-fact for Paul J. Mitchell   05/03/2018
**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 on 12/12/17.
(2) The reporting person and his wife are co-trustees of The Paul J. Mitchell Trust and the reporting person is also a beneficiary of The Paul J. Mitchell Trust originally established on November 19, 2014 and amended and restated on September 8, 2017 ("The Paul J. Mitchell Trust").
(3) This sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 12/12/17.
(4) These options are fully vested in accordance with their terms.
(5) These options were transferred from the reporting person to The Paul J. Mitchell Trust on December 11, 2017.

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