<SEC-DOCUMENT>0001137789-17-000025.txt : 20170516
<SEC-HEADER>0001137789-17-000025.hdr.sgml : 20170516
<ACCEPTANCE-DATETIME>20170516192140
ACCESSION NUMBER:		0001137789-17-000025
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170512
FILED AS OF DATE:		20170516
DATE AS OF CHANGE:		20170516

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Seagate Technology plc
		CENTRAL INDEX KEY:			0001137789
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER STORAGE DEVICES [3572]
		IRS NUMBER:				980648577
		STATE OF INCORPORATION:			L2
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		38/39 FITZWILLIAM SQUARE
		CITY:			DUBLIN 2
		STATE:			L2
		ZIP:			00000
		BUSINESS PHONE:		(353) (1) 234-3136

	MAIL ADDRESS:	
		STREET 1:		38/39 FITZWILLIAM SQUARE
		CITY:			DUBLIN 2
		STATE:			L2
		ZIP:			00000

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Seagate Technology
		DATE OF NAME CHANGE:	20090330

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SEAGATE TECHNOLOGY
		DATE OF NAME CHANGE:	20021212

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SEAGATE TECHNOLOGY HOLDINGS
		DATE OF NAME CHANGE:	20010406

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MASSARONI KENNETH M
		CENTRAL INDEX KEY:			0001423091

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31560
		FILM NUMBER:		17849994

	MAIL ADDRESS:	
		STREET 1:		SEAGATE TECHNOLOGY
		STREET 2:		920 DISC DRIVE
		CITY:			SCOTTS VALLEY
		STATE:			CA
		ZIP:			95066
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_149497688478622.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-05-12</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001137789</issuerCik>
        <issuerName>Seagate Technology plc</issuerName>
        <issuerTradingSymbol>STX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001423091</rptOwnerCik>
            <rptOwnerName>MASSARONI KENNETH M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>SEAGATE TECHNOLOGY PLC</rptOwnerStreet1>
            <rptOwnerStreet2>10200 S. DE ANZA BOULEVARD</rptOwnerStreet2>
            <rptOwnerCity>CUPERTINO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95014</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP, Interim CLO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Ordinary Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2017-05-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7500</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>42.58</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>115633</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Ordinary Shares sold under 10b5-1 Trading Plan adopted by the Reporting Person.</footnote>
        <footnote id="F2">These Ordinary Shares were sold in multiple transactions at sales prices ranging from $42.31 to $42.71, inclusive.  The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in the footnote of this Form 4.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Suhani Akhare by Power of Attorney for Kenneth M. Massaroni</signatureName>
        <signatureDate>2017-05-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
