<SEC-DOCUMENT>0001137789-17-000042.txt : 20170726
<SEC-HEADER>0001137789-17-000042.hdr.sgml : 20170726
<ACCEPTANCE-DATETIME>20170726184737
ACCESSION NUMBER:		0001137789-17-000042
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170724
FILED AS OF DATE:		20170726
DATE AS OF CHANGE:		20170726

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MURPHY JAMES J
		CENTRAL INDEX KEY:			0001234677

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31560
		FILM NUMBER:		17984015

	MAIL ADDRESS:	
		STREET 1:		C/O SEAGATE TECHNOLOGY PLC
		STREET 2:		10200 S. DEANZA BLVD
		CITY:			CUPERTINO
		STATE:			CA
		ZIP:			95014

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
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_150110923728935.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-07-24</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001234677</rptOwnerCik>
            <rptOwnerName>MURPHY JAMES J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>10200 S. DEANZA BOULEVARD</rptOwnerStreet1>
            <rptOwnerStreet2></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>EVP, Sales &amp; Marketing</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Ordinary Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2017-07-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>20963</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20963</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">On July 24, 2017, the Compensation Committee of the Board of Directors of the Issuer determined that the performance conditions were met with respect to 20,963 of the 83,850 Threshold Performance Share Units granted to Mr. Murphy on December 20, 2016. The 20,963 Ordinary Shares will vest on December 20, 2017, subject to continuous service through such date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Suhani Akhare Attorney-in-Fact for James J. Murphy</signatureName>
        <signatureDate>2017-07-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
