SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* MITCHELL PAUL J (Last) (First) (Middle) CONNAUGHT HOUSE 1 BURLINGTON ROAD (Street) DUBLIN 4 IRELAND (City) (State) (Zip)	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)
	3. Date of Earliest Transaction (Month/Day/Year) 05/01/2018
	4. If Amendment, Date of 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

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

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 Securities Underlying Derivative Security (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: 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)

Explanation of Responses:

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.

	/s/ Jennifer Baptiste, attorney-in-fact for Paul J. Mitchell	05/03/2018
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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