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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Fmyz9bTUBkaFrvQ7aqVEbunwa3d7A2RmPI5JfY2Hw3BtiorYfBg6/dcwUDtEvZlc
 +YWu3VU7iNc2gQ64yZRsrQ==

<SEC-DOCUMENT>0001104315-08-000002.txt : 20080424
<SEC-HEADER>0001104315-08-000002.hdr.sgml : 20080424
<ACCEPTANCE-DATETIME>20080424210221
ACCESSION NUMBER:		0001104315-08-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080422
FILED AS OF DATE:		20080424
DATE AS OF CHANGE:		20080424

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			JAIN ANIL K
		CENTRAL INDEX KEY:			0001104315
		STANDARD INDUSTRIAL CLASSIFICATION:	OPTICAL INSTRUMENTS & LENSES [3827]
		STATE OF INCORPORATION:			MN
		FISCAL YEAR END:			0331

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-16106
		FILM NUMBER:		08775745

	BUSINESS ADDRESS:	
		STREET 1:		2950 NE 84TH LANE
		CITY:			BLAINE
		STATE:			MN
		ZIP:			55434
		BUSINESS PHONE:		6127844995

	MAIL ADDRESS:	
		STREET 2:		2950 NE 84TH LN
		CITY:			BLAINE MINNESOTA
		STATE:			MN
		ZIP:			55449

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Clearfield, Inc.
		CENTRAL INDEX KEY:			0000796505
		STANDARD INDUSTRIAL CLASSIFICATION:	OPTICAL INSTRUMENTS & LENSES [3827]
		IRS NUMBER:				411347235
		STATE OF INCORPORATION:			MN
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		5480 NATHAN LANE NORTH
		STREET 2:		SUITE 120
		CITY:			PLYMOUTH
		STATE:			MN
		ZIP:			55442
		BUSINESS PHONE:		763-476-6866

	MAIL ADDRESS:	
		STREET 1:		5480 NATHAN LANE NORTH
		STREET 2:		SUITE 120
		CITY:			PLYMOUTH
		STATE:			MN
		ZIP:			55442

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	APA Enterprises, Inc.
		DATE OF NAME CHANGE:	20041116

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	APA OPTICS INC /MN/
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-04-22</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0000796505</issuerCik>
        <issuerName>Clearfield, Inc.</issuerName>
        <issuerTradingSymbol>CLFD</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001104315</rptOwnerCik>
            <rptOwnerName>JAIN ANIL K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5480 NATHAN LANE N</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 120</rptOwnerStreet2>
            <rptOwnerCity>PLYMOUTH MINNESOTA</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55442</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2008-04-23</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.42</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1670302</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2008-04-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>11200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.4</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1659102</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2008-04-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1.39</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1658702</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <remarks>This is part of 10b5-1 transaction</remarks>

    <ownerSignature>
        <signatureName>ANIL K JAIN</signatureName>
        <signatureDate>2008-04-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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