<SEC-DOCUMENT>0001127602-17-005076.txt : 20170210
<SEC-HEADER>0001127602-17-005076.hdr.sgml : 20170210
<ACCEPTANCE-DATETIME>20170210201635
ACCESSION NUMBER:		0001127602-17-005076
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20161231
FILED AS OF DATE:		20170210
DATE AS OF CHANGE:		20170210

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BIBERSTEIN KATHRYN L
		CENTRAL INDEX KEY:			0001235595

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35299
		FILM NUMBER:		17595397

	MAIL ADDRESS:	
		STREET 1:		88 SIDNEY ST
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			021394136
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>form5.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2016-12-31</periodOfReport>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001235595</rptOwnerCik>
            <rptOwnerName>BIBERSTEIN KATHRYN L</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>EVP/CAO/CCO Alks Inc; Sec ALKS</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Ordinary Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>38687</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Ordinary Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>36848</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 2015 GRAT</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Ordinary Shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>57152</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 2016 GRAT</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Excludes 57,152 shares previously owned indirectly by the Kathryn L. Biberstein 2015 Grantor Retained Annuity Trust dated December 11, 2015 (the &quot;2015 GRAT&quot;), which were first transferred to the reporting person's direct beneficial ownership on December 13, 2014 pursuant to an annuity payment under the 2015 GRAT and subsequently contributed to the Kathryn L. Biberstein 2016 Annuity Trust dated December 9, 2016 (the &quot;2016 GRAT&quot;) on December 14, 2016. Both the annuity payment and the contribution to the 2016 GRAT were exempt from reporting obligations by virtue of Rule 16a-13 promulgated under the Securities Exchange Act of 1934, as amended.</footnote>
        <footnote id="F2">Shares held by the 2015 GRAT.  The Reporting Person is a trustee and beneficiary of the 2015 GRAT and may be deemed to hold voting and dispositive power with regard to the reported shares held by the 2015 GRAT.</footnote>
        <footnote id="F3">Shares held by 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.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Jennifer Baptiste, attorney-in-fact for Kathryn L. Biberstein</signatureName>
        <signatureDate>2017-02-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
