<SEC-DOCUMENT>0001753159-25-000006.txt : 20251210
<SEC-HEADER>0001753159-25-000006.hdr.sgml : 20251210
<ACCEPTANCE-DATETIME>20251210213324
ACCESSION NUMBER:		0001753159-25-000006
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251208
FILED AS OF DATE:		20251210
DATE AS OF CHANGE:		20251210

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Talasaz AmirAli
		CENTRAL INDEX KEY:			0001753159
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38683
		FILM NUMBER:		251563344

	MAIL ADDRESS:	
		STREET 1:		3100 HANOVER STREET
		CITY:			PALO ALTO
		STATE:			CA
		ZIP:			94304

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Guardant Health, Inc.
		CENTRAL INDEX KEY:			0001576280
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MEDICAL LABORATORIES [8071]
		ORGANIZATION NAME:           	08 Industrial Applications and Services
		EIN:				454139254
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3100 HANOVER STREET
		CITY:			PALO ALTO
		STATE:			CA
		ZIP:			94304
		BUSINESS PHONE:		855-698-8887

	MAIL ADDRESS:	
		STREET 1:		3100 HANOVER STREET
		CITY:			PALO ALTO
		STATE:			CA
		ZIP:			94304
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1765420401.xml
<DESCRIPTION>FORM 4
<TEXT>
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    <periodOfReport>2025-12-08</periodOfReport>

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        <issuerName>Guardant Health, Inc.</issuerName>
        <issuerTradingSymbol>GH</issuerTradingSymbol>
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            <rptOwnerCik>0001753159</rptOwnerCik>
            <rptOwnerName>Talasaz AmirAli</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3100 HANOVER STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PALO ALTO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94304</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Co-Chief Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

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                <value>Common Stock</value>
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                <value>2025-12-08</value>
            </transactionDate>
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                <transactionFormType>5</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value>E</value>
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            <transactionAmounts>
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                    <value>387946</value>
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                    <value>Shares held by Maryam Eskandari 2018 Children's Remainder Trust, Dated 9/25/2018</value>
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        <nonDerivativeTransaction>
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                    <value>15000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>104.2083</value>
                    <footnoteId id="F2"/>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
                    <value>203223</value>
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                <directOrIndirectOwnership>
                    <value>I</value>
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                    <value>Shares held by AmirAli Talasaz 2018 Children's Remainder Trust, Dated 9/25/2018</value>
                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-12-08</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>30760</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>105.3372</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <sharesOwnedFollowingTransaction>
                    <value>172463</value>
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                <directOrIndirectOwnership>
                    <value>I</value>
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                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2025-12-08</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
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                    <value>4240</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>106</value>
                </transactionPricePerShare>
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        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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                <transactionFormType>4</transactionFormType>
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                    <footnoteId id="F2"/>
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                <transactionAcquiredDisposedCode>
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                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Shares held by Maryam Eskandari 2018 Children's Remainder Trust, Dated 9/25/2018</value>
                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
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                <transactionPricePerShare>
                    <value>105.3372</value>
                    <footnoteId id="F3"/>
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                    <value>172463</value>
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                <directOrIndirectOwnership>
                    <value>I</value>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2025-12-08</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>4240</value>
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                <transactionPricePerShare>
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                    <value>D</value>
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                    <value>I</value>
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                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Reflects changes in form of ownership from Talasaz Investments LP due to the transfer of shares to The AmirAli Talasaz 2018 Children's Remainder Trust dated 9/25/2018, and Maryam Eskandari 2018 Children's Remainder Trust, dated 9/25/2018.</footnote>
        <footnote id="F2">Represents the weighted average sales price per share. These shares were sold in multiple transactions at prices ranging  from $104.00 to $104.75. The Reporting Person has provided to the Issuer, and undertakes to provide to the staff of the Securities and Exchange Commission or any security holder of the Issuer, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
        <footnote id="F3">Represents the weighted average sales price per share. These shares were sold in multiple transactions at prices ranging  from $105.00 to $105.81. The Reporting Person has provided to the Issuer, and undertakes to provide to the staff of the Securities and Exchange Commission or any security holder of the Issuer, upon request, full information regarding the number of shares sold at each separate price within the range.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ John G. Saia, as attorney-in-fact for AmirAli Talasaz</signatureName>
        <signatureDate>2025-12-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
