-----BEGIN PRIVACY-ENHANCED MESSAGE-----
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,
 K6HHELnvC4dKhSGq3xASytj4EctDTjteMuzvQ3eLTiLYyOyHkydtuoLQz77+qb4I
 1TA+FSt0QdnsWrpmnOLEJA==

<SEC-DOCUMENT>0001234951-05-000001.txt : 20050817
<SEC-HEADER>0001234951-05-000001.hdr.sgml : 20050817
<ACCEPTANCE-DATETIME>20050817165309
ACCESSION NUMBER:		0001234951-05-000001
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050816
FILED AS OF DATE:		20050817
DATE AS OF CHANGE:		20050817

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STEER ROBERT
		CENTRAL INDEX KEY:			0001234951

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-03390
		FILM NUMBER:		051033868

	BUSINESS ADDRESS:	
		STREET 1:		SEABOARD CORP.
		STREET 2:		9000 WEST 67TH STREET
		CITY:			SHAWNEE MISSION
		STATE:			KS
		ZIP:			66201

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SEABOARD CORP /DE/
		CENTRAL INDEX KEY:			0000088121
		STANDARD INDUSTRIAL CLASSIFICATION:	MEAT PACKING PLANTS [2011]
		IRS NUMBER:				042260388
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		9000 W. 67TH STREET
		CITY:			SHAWNEE MISSION
		STATE:			KS
		ZIP:			66202
		BUSINESS PHONE:		9136768800

	MAIL ADDRESS:	
		STREET 1:		9000 W. 67TH STREET
		CITY:			SHAWNEE MISSION
		STATE:			KS
		ZIP:			66202

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SEABOARD ALLIED MILLING CORP
		DATE OF NAME CHANGE:	19820328

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HATHAWAY BAKERIES INC
		DATE OF NAME CHANGE:	19710315
</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>2005-08-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000088121</issuerCik>
        <issuerName>SEABOARD CORP /DE/</issuerName>
        <issuerTradingSymbol>SEB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001234951</rptOwnerCik>
            <rptOwnerName>STEER ROBERT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>9000 WEST 67TH STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MERRIAM</rptOwnerCity>
            <rptOwnerState>KS</rptOwnerState>
            <rptOwnerZipCode>66202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. V.P., CFO &amp; Treasurer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-08-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>250</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1227.4</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>/s/ Robert L. Steer</signatureName>
        <signatureDate>2005-08-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----