-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 KaS0I7o/SJIxd9v75Sp8SIejPyOi6VgCobuyITgW2ym8gPGT2WgwT/71sQ3SZTDk
 YiT+FJPzQr1xf17EwM00OA==

<SEC-DOCUMENT>0001261739-03-000001.txt : 20030828
<SEC-HEADER>0001261739-03-000001.hdr.sgml : 20030828
<ACCEPTANCE-DATETIME>20030828183643
ACCESSION NUMBER:		0001261739-03-000001
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030821
FILED AS OF DATE:		20030828

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HOUSSEIN AHMET
		CENTRAL INDEX KEY:			0001261739

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-15071
		FILM NUMBER:		03872148

	MAIL ADDRESS:	
		STREET 1:		691 S MILPITAS BLVD
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ADAPTEC INC
		CENTRAL INDEX KEY:			0000709804
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER COMMUNICATIONS EQUIPMENT [3576]
		IRS NUMBER:				942748530
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		691 S MILPITAS BLVD
		STREET 2:		M/S25
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035
		BUSINESS PHONE:		4089458600

	MAIL ADDRESS:	
		STREET 1:		691 SOUTH MILPITAS BLVD
		STREET 2:		M/S25
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2003-08-21</periodOfReport>


    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000709804</issuerCik>
        <issuerName>ADAPTEC INC</issuerName>
        <issuerTradingSymbol>ADPT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001261739</rptOwnerCik>
            <rptOwnerName>HOUSSEIN AHMET</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>691 S MILPITAS BLVD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILPITAS</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95035</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP &amp; GM Storage Solutions Gp</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>

        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2923</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>

        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>None</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>

    </nonDerivativeTable>

    <derivativeTable>

        <derivativeHolding>
            <securityTitle>
                <value>Incentive Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>14.75</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2007-04-24</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2009-04-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>30708</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>

        <derivativeHolding>
            <securityTitle>
                <value>Non Qualified Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>14.75</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2007-04-24</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2009-04-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4292</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>

        <derivativeHolding>
            <securityTitle>
                <value>Incentive Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.511</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2006-09-30</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2009-09-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3125</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>

        <derivativeHolding>
            <securityTitle>
                <value>Non Qualified Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.511</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2006-09-30</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2009-09-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>46875</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>

        <derivativeHolding>
            <securityTitle>
                <value>Non Qualified Stock Option</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.3</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2007-08-04</value>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2010-08-04</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>50000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>

    </derivativeTable>

    <footnotes>
        <footnote id="F1">Mr. Houssein was granted a total of 35,000 stock options on 4/30/2002, of which 30,708 are considered Incentive Stock Options and 4,292 are considered Non Qualified Stock Options. These options vest and become exercisable as to 20% of the aggregate options on 4/24/2003, and the balance in equal quarterly installments thereafter through 4/24/2007.</footnote>
        <footnote id="F2">Mr. Houssein was granted a total of 50,000 stock options on 9/30/2002, of which 46,875 are considered Non Qualified Stock Options and 3,125 are considered Incentive Stock Options. These options vest and become exercisable in equal quarterly installments through 9/30/2006.</footnote>
        <footnote id="F3">These options become vested and exercisable as to 20% of the total option immediately at grant. The remaining 80% vests and becomes exercisable in equal quarterly installments through 8/4/2007.</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>AHMET HOUSSEIN</signatureName>
        <signatureDate>2003-08-28</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----