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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 LizGlMM4dhx5PfrYX39XBoDTHCJuhXXNZZiqSRMZJlo0XzRPdeUYH+40Nu/B/ise
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<SEC-DOCUMENT>0001104659-04-039107.txt : 20041210
<SEC-HEADER>0001104659-04-039107.hdr.sgml : 20041210
<ACCEPTANCE-DATETIME>20041210142145
ACCESSION NUMBER:		0001104659-04-039107
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041208
FILED AS OF DATE:		20041210
DATE AS OF CHANGE:		20041210

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DECODE GENETICS INC
		CENTRAL INDEX KEY:			0001022974
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMMERCIAL PHYSICAL & BIOLOGICAL RESEARCH [8731]
		IRS NUMBER:				043326704
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		8 STURLUGATA
		STREET 2:		IS 101
		CITY:			REYJKAVIK
		STATE:			K6
		ZIP:			00000
		BUSINESS PHONE:		011 354 570 1900

	MAIL ADDRESS:	
		STREET 1:		8 STURLUGATA
		STREET 2:		IS 101
		CITY:			REYKJAVIK
		STATE:			K6
		ZIP:			00000

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STEFANSSON KARI
		CENTRAL INDEX KEY:			0001117008
		STATE OF INCORPORATION:			K6
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30469
		FILM NUMBER:		041195736

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		354-570-1900

	MAIL ADDRESS:	
		STREET 1:		DECODE GENETICS, INC.
		STREET 2:		LYNGHALS 1
		CITY:			REYKJAVIK
		STATE:			K6
		ZIP:			00000
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
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    <schemaVersion>X0202</schemaVersion>

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        <issuerName>DECODE GENETICS INC</issuerName>
        <issuerTradingSymbol>DCGN</issuerTradingSymbol>
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            <rptOwnerName>STEFANSSON KARI</rptOwnerName>
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            <rptOwnerStreet1>C/O DECODE GENETICS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>STURLUGATA 8</rptOwnerStreet2>
            <rptOwnerCity>REYKJAVIK</rptOwnerCity>
            <rptOwnerState>K6</rptOwnerState>
            <rptOwnerZipCode>IS-101</rptOwnerZipCode>
            <rptOwnerStateDescription>ICELAND</rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; CEO</officerTitle>
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                <transactionCode>S</transactionCode>
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            <transactionTimeliness>
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            <transactionAmounts>
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                <transactionPricePerShare>
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            <transactionDate>
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            <transactionCoding>
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                <transactionPricePerShare>
                    <value>6.6535</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2740292</value>
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            <ownershipNature>
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                    <value>D</value>
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        <nonDerivativeTransaction>
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            <transactionDate>
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            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
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            <transactionTimeliness>
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            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
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                <transactionPricePerShare>
                    <value>6.70</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2735292</value>
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                <value>Common Stock</value>
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            <transactionDate>
                <value>2004-12-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
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                <transactionPricePerShare>
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                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2727792</value>
                </sharesOwnedFollowingTransaction>
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            <transactionDate>
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                <transactionPricePerShare>
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                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
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                </sharesOwnedFollowingTransaction>
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        </nonDerivativeTransaction>
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    <ownerSignature>
        <signatureName>/s/ Tanya Zharov, Attorney-in-Fact</signatureName>
        <signatureDate>2004-12-10</signatureDate>
    </ownerSignature>
</ownershipDocument>

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