<SEC-DOCUMENT>0001660280-20-000064.txt : 20200601
<SEC-HEADER>0001660280-20-000064.hdr.sgml : 20200601
<ACCEPTANCE-DATETIME>20200601172346
ACCESSION NUMBER:		0001660280-20-000064
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200528
FILED AS OF DATE:		20200601
DATE AS OF CHANGE:		20200601

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:		20934710

	MAIL ADDRESS:	
		STREET 1:		C/O TENABLE HOLDINGS, INC.
		STREET 2:		7021 COLUMBIA GATEWAY DRIVE, SUITE 500
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046

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:		7021 COLUMBIA GATEWAY DRIVE, SUITE 500
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046
		BUSINESS PHONE:		410-872-0555

	MAIL ADDRESS:	
		STREET 1:		7021 COLUMBIA GATEWAY DRIVE, SUITE 500
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_159104660897679.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-05-28</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>7021 COLUMBIA GATEWAY DRIVE, SUITE 500</rptOwnerStreet2>
            <rptOwnerCity>COLUMBIA</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>21046</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <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="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3294982</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>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>86</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>48890</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2020-05-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6677</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>6677.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6677</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">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="F2">Mary Kathryn Braden Huffard and Jonathan M. Forster, as Trustees of The Three Suns 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">The Trustees of the John Cloyd Huffard Jr Revocable Trust are John Cloyd Huffard Jr and Mary Kathryn Braden Huffard.</footnote>
        <footnote id="F4">Each restricted stock unit (&quot;RSU&quot;) represents a contingent right to receive one share of Issuer common stock.</footnote>
        <footnote id="F5">100% of the shares underlying the RSUs vest on the earlier of May 28, 2021 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>2020-06-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
