<SEC-DOCUMENT>0001660280-22-000096.txt : 20220526
<SEC-HEADER>0001660280-22-000096.hdr.sgml : 20220526
<ACCEPTANCE-DATETIME>20220526170305
ACCESSION NUMBER:		0001660280-22-000096
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20220525
FILED AS OF DATE:		20220526
DATE AS OF CHANGE:		20220526

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Huffard John C Jr
		CENTRAL INDEX KEY:			0001747299

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38600
		FILM NUMBER:		22971150

	MAIL ADDRESS:	
		STREET 1:		C/O TENABLE HOLDINGS, INC.
		STREET 2:		6100 MERRIWEATHER DRIVE
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21044

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Tenable Holdings, Inc.
		CENTRAL INDEX KEY:			0001660280
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				475580846
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6100 MERRIWEATHER DRIVE
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21044
		BUSINESS PHONE:		410-872-0555

	MAIL ADDRESS:	
		STREET 1:		6100 MERRIWEATHER DRIVE
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21044
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_165359896496271.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
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<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2022-05-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001660280</issuerCik>
        <issuerName>Tenable Holdings, Inc.</issuerName>
        <issuerTradingSymbol>TENB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001747299</rptOwnerCik>
            <rptOwnerName>Huffard John C Jr</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O TENABLE HOLDINGS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>6100 MERRIWEATHER DRIVE</rptOwnerStreet2>
            <rptOwnerCity>COLUMBIA</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>21044</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2022-05-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4962</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7135</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>31847</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Spouse</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>390183</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
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                <sharesOwnedFollowingTransaction>
                    <value>53588</value>
                    <footnoteId id="F3"/>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
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                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F4"/>
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            </ownershipNature>
        </nonDerivativeHolding>
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    <derivativeTable>
        <derivativeTransaction>
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                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
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            <transactionDate>
                <value>2022-05-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4962</value>
                </transactionShares>
                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F6"/>
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            <expirationDate>
                <footnoteId id="F6"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4962.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2022-05-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4044</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F7"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4044.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4044</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Mary Kathryn Braden Huffard as Trustee of the Mary Kathryn Braden Huffard Revocable Trust U/T/A dated March 2, 2012.</footnote>
        <footnote id="F2">Mary Kathryn Braden Huffard and Jonathan M. Forster, as Trustees of The Three Suns Non-Exempt Irrevocable Trust U/T/A dated March 2, 2012.  The Reporting Person's spouse and children are the beneficiaries of this trust.</footnote>
        <footnote id="F3">In October of 2021, The Reporting Person contributed 6,677 shares to the John Cloyd Huffard Jr Revocable Trust U/T/A dated March 2, 2012.</footnote>
        <footnote id="F4">The Trustees of the John Cloyd Huffard Jr Revocable Trust U/T/A dated March 2, 2012 are John Cloyd Huffard Jr and Mary Kathryn Braden Huffard.</footnote>
        <footnote id="F5">Each restricted stock unit (&quot;RSU&quot;) represents a contingent right to receive one share of Issuer common stock.</footnote>
        <footnote id="F6">100% of the shares underlying the RSUs vested on May 25, 2022.</footnote>
        <footnote id="F7">100% of the shares underlying the RSUs vest on the earlier of May 25, 2023 or the Issuer's next annual shareholder meeting, subject to the Reporting Person's continuous service with the Issuer as of the applicable vesting date, and subject to accelerated vesting in specified circumstances.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ David Bartholomew, Attorney-in-Fact</signatureName>
        <signatureDate>2022-05-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
