<SEC-DOCUMENT>0001441683-19-000204.txt : 20191127
<SEC-HEADER>0001441683-19-000204.hdr.sgml : 20191127
<ACCEPTANCE-DATETIME>20191127161847
ACCESSION NUMBER:		0001441683-19-000204
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20191126
FILED AS OF DATE:		20191127
DATE AS OF CHANGE:		20191127

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MITCHELL DAVID LEON
		CENTRAL INDEX KEY:			0001255235

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38098
		FILM NUMBER:		191258136

	MAIL ADDRESS:	
		STREET 1:		11955 DEMOCRACY DRIVE
		STREET 2:		SUITE 1700
		CITY:			RESTON
		STATE:			VA
		ZIP:			20190

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			APPIAN CORP
		CENTRAL INDEX KEY:			0001441683
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				541956084
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		7950 JONES BRANCH DRIVE
		CITY:			TYSONS
		STATE:			VA
		ZIP:			22102
		BUSINESS PHONE:		703-442-8844

	MAIL ADDRESS:	
		STREET 1:		7950 JONES BRANCH DRIVE
		CITY:			TYSONS
		STATE:			VA
		ZIP:			22102
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_157488951022237.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-11-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001441683</issuerCik>
        <issuerName>APPIAN CORP</issuerName>
        <issuerTradingSymbol>APPN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001255235</rptOwnerCik>
            <rptOwnerName>MITCHELL DAVID LEON</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O APPIAN CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>7950 JONES BRANCH DRIVE</rptOwnerStreet2>
            <rptOwnerCity>TYSONS</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22102</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior VP, Worldwide Sales</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-11-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>540</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>44.82</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9797</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-11-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>210</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>43.80</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9587</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 21, 2019.</footnote>
        <footnote id="F2">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $43.43 to $44.41, inclusive. The Reporting Person undertakes to provide to Appian Corporation, any security holder of Appian Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (2) and (3).</footnote>
        <footnote id="F3">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $44.55 to $45.08, inclusive.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Angela Patterson, Attorney-in-Fact</signatureName>
        <signatureDate>2019-11-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
