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
OMB APPROVAL
OMB Number: 3235-0287
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
BIBERSTEIN KATHRYN L
  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)
EVP/CAO/CCO/CRO Alks Inc;
(Last)
(First)
(Middle)
852 WINTER ST.
3. Date of Earliest Transaction (Month/Day/Year)
02/16/2018
(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 02/17/2018   M   3,750 A $ 0 15,974 D  
Ordinary Shares 02/17/2018   F   1,148 D $ 67.26 14,826 D  
Ordinary Shares 02/20/2018   M   6,582 A $ 11.74 21,408 D  
Ordinary Shares 02/20/2018   M   3,588 A $ 18.105 24,996 D  
Ordinary Shares 02/20/2018   M   4,107 A $ 16.55 29,103 D  
Ordinary Shares 02/20/2018   M   2,965 A $ 33.72 32,068 D  
Ordinary Shares               28,856 I By 2016 GRAT (1)
Ordinary Shares               113,017 I By 2017 GRAT (2)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)

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 02/16/2018   A   17,500   02/16/2019(3)   (3) Ordinary Shares 17,500 $ 0 17,500 D  
Employee Stock Option (Right to Buy) $ 67.26 02/16/2018   A   71,000   02/16/2019(4) 02/16/2028 Ordinary Shares 71,000 $ 0 71,000 D  
Restricted Stock Unit Award $ 0 02/17/2018   M     3,750 02/17/2018(5)   (5) Ordinary Shares 3,750 $ 0 11,250 D  
Employee Stock Option (Right to Buy) $ 11.74 02/20/2018   M     6,582   (6) 05/17/2020 Ordinary Shares 6,582 $ 0 77,983 D  
Employee Stock Option (Right to Buy) $ 18.105 02/20/2018   M     3,588   (6) 05/20/2021 Ordinary Shares 3,588 $ 0 94,477 D  
Employee Stock Option (Right to Buy) $ 16.55 02/20/2018   M     4,107   (6) 05/21/2022 Ordinary Shares 4,107 $ 0 113,958 D  
Employee Stock Option (Right to Buy) $ 33.72 02/20/2018   M     2,965   (6) 05/28/2023 Ordinary Shares 2,965 $ 0 77,035 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
BIBERSTEIN KATHRYN L
852 WINTER ST.
WALTHAM, MA 02451
      EVP/CAO/CCO/CRO Alks Inc;  

Signatures

 /s/ Jennifer Baptiste, attorney-in-fact for Kathryn L. Biberstein   02/21/2018
**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) Shares held by the Kathryn L. Biberstein 2016 Annuity Trust dated December 9, 2016 (the "2016 GRAT"). The Reporting Person is a trustee and beneficiary of the 2016 GRAT and may be deemed to hold voting and dispositive power with regard to the reported shares held by the 2016 GRAT.
(2) Shares held by the Kathryn L. Biberstein 2017 Annuity Trust dated December 11, 2017 (the "2017 GRAT"). The Reporting Person is a trustee and beneficiary of the 2017 GRAT and may be deemed to hold voting and dispositive power with regard to the reported shares held by the 2017 GRAT.
(3) Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 2/16/19.
(4) Shares subject to the stock option award vest in four equal annual installments commencing on 2/16/2019.
(5) Shares subject to the restricted stock unit award vest in equal annual installments over a four year period, commencing on 2/17/18.
(6) These options are fully vested in accordance with their terms.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.