<SEC-DOCUMENT>0001127602-23-006516.txt : 20230222
<SEC-HEADER>0001127602-23-006516.hdr.sgml : 20230222
<ACCEPTANCE-DATETIME>20230222165942
ACCESSION NUMBER:		0001127602-23-006516
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230218
FILED AS OF DATE:		20230222
DATE AS OF CHANGE:		20230222

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Nichols Christian Todd
		CENTRAL INDEX KEY:			0001813312

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35299
		FILM NUMBER:		23654293

	MAIL ADDRESS:	
		STREET 1:		852 WINTER STREET
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Alkermes plc.
		CENTRAL INDEX KEY:			0001520262
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				981007018
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		CONNAUGHT HOUSE
		STREET 2:		1 BURLINGTON ROAD
		CITY:			DUBLIN 4
		STATE:			L2
		ZIP:			00000
		BUSINESS PHONE:		00-353-1-772-8000

	MAIL ADDRESS:	
		STREET 1:		CONNAUGHT HOUSE
		STREET 2:		1 BURLINGTON ROAD
		CITY:			DUBLIN 4
		STATE:			L2
		ZIP:			00000

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ANTLER SCIENCE TWO PLC
		DATE OF NAME CHANGE:	20110804

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Antler Science Two Ltd
		DATE OF NAME CHANGE:	20110509
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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    <periodOfReport>2023-02-18</periodOfReport>

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        <issuerCik>0001520262</issuerCik>
        <issuerName>Alkermes plc.</issuerName>
        <issuerTradingSymbol>ALKS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001813312</rptOwnerCik>
            <rptOwnerName>Nichols Christian Todd</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>852 WINTER ST.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WALTHAM</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02451</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>SVP, Chief Commercial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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                <value>Ordinary Shares</value>
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                <transactionFormType>4</transactionFormType>
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        </nonDerivativeTransaction>
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                <value>2023-02-18</value>
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            <transactionAmounts>
                <transactionShares>
                    <value>6230</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
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            <expirationDate>
                <footnoteId id="F3"/>
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            <underlyingSecurity>
                <underlyingSecurityTitle>
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                </underlyingSecurityTitle>
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                </underlyingSecurityShares>
            </underlyingSecurity>
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                </sharesOwnedFollowingTransaction>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
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                <transactionShares>
                    <value>3824</value>
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                <transactionPricePerShare>
                    <footnoteId id="F1"/>
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    <footnotes>
        <footnote id="F1">Each restricted stock unit represents a contingent right to receive one ordinary share.</footnote>
        <footnote id="F2">These ordinary shares were acquired by the reporting person as a result of the vesting of performance-vesting restricted stock unit awards granted to the reporting person on February 20, 2020 with a three-year performance period that ended on December 31, 2022 (the &quot;2020 PRSUs&quot;). The vesting of this portion of the 2020 PRSUs was triggered by the determination of achievement of certain pre-specified performance goals and application of a total shareholder return modifier and represents the final vesting event under the 2020 PRSUs.</footnote>
        <footnote id="F3">Shares subject to the restricted stock unit award vest in four equal annual installments, commencing on 2/18/2023.</footnote>
        <footnote id="F4">Shares subject to the restricted stock unit award vest in four equal annual installments, commencing on 2/20/2021.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Shantale Greenson, attorney-in-fact for Christian Todd Nichols</signatureName>
        <signatureDate>2023-02-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
