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* BIBERSTEIN KATHRYN L (Last) (First) (Middle) 852 WINTER ST. (Street) WALTHAM MA 02451 (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) Director 10% Owner X Officer (give title below) Other (specify below) EVP/CAO/CCO/CRO Alks Inc;
	3. Date of Earliest Transaction (Month/Day/Year) 02/16/2018
	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	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)

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
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

Explanation of Responses:

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.

	/s/ Jennifer Baptiste, attorney-in-fact for Kathryn L. Biberstein	02/21/2018
	** 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).
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