<SEC-DOCUMENT>0001137789-17-000051.txt : 20170912
<SEC-HEADER>0001137789-17-000051.hdr.sgml : 20170912
<ACCEPTANCE-DATETIME>20170912214334
ACCESSION NUMBER:		0001137789-17-000051
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170909
FILED AS OF DATE:		20170912
DATE AS OF CHANGE:		20170912

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MOSLEY WILLIAM D
		CENTRAL INDEX KEY:			0001388390

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31560
		FILM NUMBER:		171082128

	MAIL ADDRESS:	
		STREET 1:		SEAGATE TECHNOLOGY
		STREET 2:		920 DISC DRIVE
		CITY:			SCOTTS VALLEY
		STATE:			CA
		ZIP:			95066

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>
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<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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        <issuerName>Seagate Technology plc</issuerName>
        <issuerTradingSymbol>STX</issuerTradingSymbol>
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            <rptOwnerName>MOSLEY WILLIAM D</rptOwnerName>
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            <rptOwnerStreet1>SEAGATE TECHNOLOGY PLC</rptOwnerStreet1>
            <rptOwnerStreet2>10200 S. DE ANZA BOULEVARD</rptOwnerStreet2>
            <rptOwnerCity>CUPERTINO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95014</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; COO</officerTitle>
            <otherText></otherText>
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            <transactionDate>
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                    <value>0</value>
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                <transactionAcquiredDisposedCode>
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                </underlyingSecurityTitle>
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                    <value>130480.0</value>
                </underlyingSecurityShares>
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                    <value>D</value>
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        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>NQ Stock Option Grant</value>
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                <value>30.95</value>
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                    <value>253188</value>
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                    <value>0</value>
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                    <value>A</value>
                </transactionAcquiredDisposedCode>
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                <value>2024-09-11</value>
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    <footnotes>
        <footnote id="F1">These Ordinary Shares are withheld securities to cover tax liabilities incident to the vesting of securities previously reported on one or more Forms 4 by the Reporting Person in accordance with Rule 16b-3.</footnote>
        <footnote id="F2">Each performance-based restricted share unit (&quot;PSU&quot;) represents a contingent right to receive one share of Seagate Technology plc's (&quot;Seagate&quot;) ordinary shares. The number of PSUs that may be earned is between 0% and 200% of the target number of PSUs and shall vest based on ROIC and relative TSR performance over the three-year performance period ending September 11, 2020.</footnote>
        <footnote id="F3">The PSUs vest on or after September 11, 2020 subject to the achievement and certification of the performance criteria.</footnote>
        <footnote id="F4">Options granted to the Reporting Person under the Issuer's 2012 Equity Incentive Plan are subject to a four-year vesting schedule.  Subject to continuous employment, one quarter of the option shares will vest on September 11, 2018.  The remaining option shares will vest in equal monthly installments over the 36 months following September 11, 2018.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Suhani Akhare Attorney-in-Fact for William D. Mosley</signatureName>
        <signatureDate>2017-09-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
