<SEC-DOCUMENT>0001628280-17-008551.txt : 20170810
<SEC-HEADER>0001628280-17-008551.hdr.sgml : 20170810
<ACCEPTANCE-DATETIME>20170810202335
ACCESSION NUMBER:		0001628280-17-008551
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20170810
FILED AS OF DATE:		20170810
DATE AS OF CHANGE:		20170810

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Diamond Michael E
		CENTRAL INDEX KEY:			0001590840

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35231
		FILM NUMBER:		171022756

	MAIL ADDRESS:	
		STREET 1:		600 B. STREET
		STREET 2:		SUITE 100
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92101

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MITEK SYSTEMS INC
		CENTRAL INDEX KEY:			0000807863
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER PERIPHERAL EQUIPMENT, NEC [3577]
		IRS NUMBER:				870418827
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		600 B STREET
		STREET 2:		SUITE 100
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92101
		BUSINESS PHONE:		619-269-6800

	MAIL ADDRESS:	
		STREET 1:		600 B STREET
		STREET 2:		SUITE 100
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92101
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_150241100195932.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-08-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000807863</issuerCik>
        <issuerName>MITEK SYSTEMS INC</issuerName>
        <issuerTradingSymbol>MITK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001590840</rptOwnerCik>
            <rptOwnerName>Diamond Michael E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>600 B STREET, SUITE 100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92101</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>General Manager</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Performance Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2017-08-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>150000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Sock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>150000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>150000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each performance restricted stocked unit represents a contingent right to receive one share of Mitek common stock. No performance restricted stock unit vests (and thus no shares of common stock are issued) unless the fair market value of Mitek's common stock at the end of a set performance period or upon a change of control during such performance period is equal to or exceeds $16.00 per share. To incentivize relative performance of Mitek's stock price, reduced vesting could occur in the event Mitek's common stock price appreciation during the performance period underperforms against the Russell 2000 Index.</footnote>
        <footnote id="F2">The fair market value of Mitek's common stock at the end of the performance period is determined based on the average closing price of Mitek's common stock for the last 20 trading days of the performance period. The fair market value of Mitek's common stock upon a change of control shall equal (i) the consideration to be received by Mitek's stockholders with respect to one share of Mitek common stock upon such change of control or (ii) upon an asset sale, the consideration that would be distributable to Mitek's stockholders with respect to each share of Mitek common stock if Mitek distributed all of the consideration received in connection with the asset sale to its stockholders, less adjustments for debt, expenses and other amounts.</footnote>
        <footnote id="F3">The vesting date for the performance restricted stock units, if such a date occurs, will not be determined until the end of the performance period or upon a change of control during the performance period. The performance period begins on March 1, 2017 and ends on the date that is 25 trading days after the first filing of an Annual Report on Form 10-K or Quarterly Report on Form 10-Q by Mitek following September 30, 2019.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Trevor Renfield, by Power of Attorney</signatureName>
        <signatureDate>2017-08-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>ex-24.htm
<DESCRIPTION>POWER OF ATTORNEY DIAMOND MICHAEL E
<TEXT>
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<pre>
POWER OF ATTORNEY

Know all by these present, that the undersigned hereby constitutes and appoints each of Russell Clark, Jason Gray and Trevor Renfield, signing singly, the undersigned's true and lawful attorneys-in-fact to:
(1) execute for and on behalf of the undersigned, in the undersigned's capacity as an officer and/or director of Mitek Systems, Inc. (the "Company"), Forms 3, 4 and 5, in respect of securities of the Company, in accordance with Section 16(a) of the Securities Exchange Act of 1934, as amended (the "Exchange Act") and the rules thereunder;
(2) do and perform any and all acts for and on behalf of the undersigned which may be necessary or desirable to complete and execute any such Form 3, 4 or 5 and timely file such form with the United States Securities and Exchange Commission and any stock exchange or similar authority; and
(3) take any other action of any type whatsoever in connection with the foregoing which, in the opinion of such attorney-in-fact, may be of benefit to, in the best interest of, or legally required by, the undersigned, it being understood that the documents executed by such attorney-in-fact on behalf of the undersigned pursuant to this Power of Attorney shall be in such form and shall contain such terms and conditions as such attorney-in-fact may approve in such attorney-in-fact's discretion.
The undersigned hereby grants to each such attorney-in-fact full power and authority to do and perform any and every act and thing whatsoever requisite, necessary or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that such attorney-in-fact, or such attorney-in-fact's substitute or substitutes, shall lawfully do or cause to be done by virtue of this power of attorney and the rights and powers herein granted. The undersigned acknowledges that the foregoing attorneys-in-fact, in serving in such capacity at the request of the undersigned, are not assuming, nor is the Company assuming, any of the undersigned's responsibilities to comply with Section 16 of the Exchange Act.
This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file Forms 4 and 5 with respect to the undersigned's holdings of and transactions in securities issued by the Company, unless earlier revoked by the undersigned in a signed writing delivered to the foregoing attorneys-in-fact.
IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of this 28th day of April, 2017.

/s/ Michael E. Diamond
Signature

Michael E. Diamond
Printed Name
</pre>
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</SEC-DOCUMENT>
