<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2020-07-10</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001819020</rptOwnerCik>
            <rptOwnerName>Bresky Ellen S.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>9000 WEST 67TH STREET, 3RD FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SHAWNEE MISSION</rptOwnerCity>
            <rptOwnerState>KS</rptOwnerState>
            <rptOwnerZipCode>66202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>465825.69</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By LLC</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>428122.55</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By LLC</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4661</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By LLC</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3120</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1775</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F5"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The shares reported are held by Seaboard Flour LLC, (i) which is owned by the reporting person and other members of the Bresky family directly or through various trusts for their benefit, and (ii) for which the reporting person serves as the sole Manager. The reporting person disclaims beneficial ownership of the reported securities except to the extent of her pecuniary interest therein.</footnote>
        <footnote id="F2">The shares reported are held by SFC Preferred LLC, (i) which is owned by the reporting person and other members of the Bresky family directly or through various trusts for their benefit, and (ii) for which the reporting person serves as the sole Manager. The reporting person disclaims beneficial ownership of the reported securities except to the extent of her pecuniary interest therein.</footnote>
        <footnote id="F3">The shares reported are held by SJB SEB LLC, which itself is owned by the SJB 2014 Trust, established for the benefit of members of the reporting person's immediate family. The reporting person ultimately has the power to vote and dispose of the securities held by such LLC and is the Co-Trustee of the trust.  The reporting person disclaims beneficial ownership of the reported securities except to the extent of her pecuniary interest therein.</footnote>
        <footnote id="F4">The shares reported are held by the HAB 2011 Gift Trust, (i) which is for the benefit of the reporting person and other members of the Bresky family, and (ii) as to which the reporting person is the business advisor with the power to vote and dispose of the securities held by such trust. The reporting person disclaims beneficial ownership of the reported securities except to the extent of her pecuniary interest therein.</footnote>
        <footnote id="F5">The shares reported are held by the HAB Grandchildren's Trust A, (i) which is for the benefit of members of the Bresky family, including members of the reporting person's immediate family, and (ii) as to which the reporting person is the business advisor with the power to vote and dispose of the securities held by such trust. The reporting person disclaims beneficial ownership of the reported securities except to the extent of her pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Ellen S. Bresky</signatureName>
        <signatureDate>2020-07-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
