<SEC-DOCUMENT>0001140361-14-039868.txt : 20141103
<SEC-HEADER>0001140361-14-039868.hdr.sgml : 20141103
<ACCEPTANCE-DATETIME>20141103164141
ACCESSION NUMBER:		0001140361-14-039868
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20141030
FILED AS OF DATE:		20141103
DATE AS OF CHANGE:		20141103

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CODEXIS INC
		CENTRAL INDEX KEY:			0001200375
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL ORGANIC CHEMICALS [2860]
		IRS NUMBER:				710872999
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		200 PENOBSCOT DRIVE
		CITY:			REDWOOD CITY
		STATE:			CA
		ZIP:			94063
		BUSINESS PHONE:		650-421-8100

	MAIL ADDRESS:	
		STREET 1:		200 PENOBSCOT DRIVE
		CITY:			REDWOOD CITY
		STATE:			CA
		ZIP:			94063

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Cheng Pam P.
		CENTRAL INDEX KEY:			0001623746

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34705
		FILM NUMBER:		141189972

	MAIL ADDRESS:	
		STREET 1:		C/O CODEXIS, INC.
		STREET 2:		200 PENOBSCOT DRIVE
		CITY:			REDWOOD CITY
		STATE:			CA
		ZIP:			94063

	FORMER NAME:	
		FORMER CONFORMED NAME:	Cheng Pam
		DATE OF NAME CHANGE:	20141029
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2014-10-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001200375</issuerCik>
        <issuerName>CODEXIS INC</issuerName>
        <issuerTradingSymbol>CDXS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001623746</rptOwnerCik>
            <rptOwnerName>Cheng Pam P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CODEXIS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>200 PENOBSCOT DRIVE</rptOwnerStreet2>
            <rptOwnerCity>REDWOOD CITY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94063</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>2014-10-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>39215</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>39215</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted Stock. The shares vest as to one third of the shares on each yearly anniversary of October 30, 2014, provided that the Reporting Person provides continuous services to the Issuer as an employee, consultant, director or officer through each such vesting date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Doug Sheehy, Attorney-in-Fact for Pam Cheng</signatureName>
        <signatureDate>2014-11-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
