<SEC-DOCUMENT>0001104659-21-064090.txt : 20210510
<SEC-HEADER>0001104659-21-064090.hdr.sgml : 20210510
<ACCEPTANCE-DATETIME>20210510190258
ACCESSION NUMBER:		0001104659-21-064090
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210507
FILED AS OF DATE:		20210510
DATE AS OF CHANGE:		20210510

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GLENCORE INTERNATIONAL AG
		CENTRAL INDEX KEY:			0001032383

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34474
		FILM NUMBER:		21909046

	BUSINESS ADDRESS:	
		STREET 1:		BAARERMATTSTRASSE 3
		STREET 2:		P O BOX 555 CH 6341 BAAR
		CITY:			SWITZERLAND
		BUSINESS PHONE:		4142227722

	MAIL ADDRESS:	
		STREET 1:		BAARERMATTSTRASSE 3
		STREET 2:		P O BOX 555 CH 6341 BAAR
		CITY:			SWITZERLAND

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Glencore plc
		CENTRAL INDEX KEY:			0001521365
		STANDARD INDUSTRIAL CLASSIFICATION:	UNKNOWN SIC - 8880 [8880]
		STATE OF INCORPORATION:			Y9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34474
		FILM NUMBER:		21909045

	BUSINESS ADDRESS:	
		STREET 1:		BAARERMATTSTRASSE 3
		CITY:			BAAR
		STATE:			V8
		ZIP:			CH-6341
		BUSINESS PHONE:		41 41 709 2000

	MAIL ADDRESS:	
		STREET 1:		BAARERMATTSTRASSE 3
		CITY:			BAAR
		STATE:			V8
		ZIP:			CH-6341

	FORMER NAME:	
		FORMER CONFORMED NAME:	Glencore Xstrata plc
		DATE OF NAME CHANGE:	20130606

	FORMER NAME:	
		FORMER CONFORMED NAME:	GLENCORE INTERNATIONAL PLC
		DATE OF NAME CHANGE:	20110520

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CENTURY ALUMINUM CO
		CENTRAL INDEX KEY:			0000949157
		STANDARD INDUSTRIAL CLASSIFICATION:	PRIMARY PRODUCTION OF ALUMINUM [3334]
		IRS NUMBER:				133070826
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1 SOUTH WACKER DRIVE
		STREET 2:		SUITE 1000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3126963101

	MAIL ADDRESS:	
		STREET 1:		1 SOUTH WACKER DRIVE
		STREET 2:		SUITE 1000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>tm2115830d1_4.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-05-07</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000949157</issuerCik>
        <issuerName>CENTURY ALUMINUM CO</issuerName>
        <issuerTradingSymbol>CENX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001032383</rptOwnerCik>
            <rptOwnerName>GLENCORE INTERNATIONAL AG</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>BAARERMATTSTRASSE 3</rptOwnerStreet1>
            <rptOwnerStreet2>P.O. BOX 1363</rptOwnerStreet2>
            <rptOwnerCity>BAAR</rptOwnerCity>
            <rptOwnerState>V8</rptOwnerState>
            <rptOwnerZipCode>CH-6340</rptOwnerZipCode>
            <rptOwnerStateDescription>SWITZERLAND</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001521365</rptOwnerCik>
            <rptOwnerName>Glencore plc</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>BAARERMATTSTRASSE 3</rptOwnerStreet1>
            <rptOwnerStreet2>P.O. BOX 1363</rptOwnerStreet2>
            <rptOwnerCity>BAAR</rptOwnerCity>
            <rptOwnerState>V8</rptOwnerState>
            <rptOwnerZipCode>CH-6340</rptOwnerZipCode>
            <rptOwnerStateDescription>SWITZERLAND</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Cash Settled Total Return Swap</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-05-07</value>
                <footnoteId id="F4"/>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>X</transactionCode>
                <equitySwapInvolved>1</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4400000</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F5"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Glencore International AG (&quot;Glencore International&quot;), a direct wholly-owned subsidiary of Glencore plc, previously received economic exposure with respect to 4,400,000 shares of common stock pursuant to a cash-settled total return swap (the &quot;Swap&quot;) entered into between Glencore International and Citigroup Global Markets Inc. (together with its successors in interest under the Swap, &quot;Citi&quot;), with an initial expiration date of March 11, 2013 (subsequently extended to April 17, 2021).</footnote>
        <footnote id="F2">Upon expiration of the Swap, (i) Glencore International is obligated to make a cash payment to Citi with respect to any depreciation in the volume weighted average price of the common stock from the $16.6582 per share volume weighted average price calculated during the initial averaging period for the Swap in March 2011 to the volume weighted average price of the common stock during the final valuation period at the expiration of the term of the Swap, or (ii) Citi is obligated to make a cash payment to Glencore International with respect to any appreciation in such volume weighted average price during the same period.</footnote>
        <footnote id="F3">Under the terms of the Swap, generally, Glencore International was obligated to pay to Citi certain fees and commissions and Citi was obligated to pay to Glencore International an amount in cash equal to any dividends that would have been paid by the issuer on the number of shares referenced by the Swap.</footnote>
        <footnote id="F4">On April 17, 2021 the Swap expired in accordance with its terms and a net settlement amount of $4,039,728 (equal to the difference between (i) a final valuation amount based on the volume weighted average price of the common stock during a final valuation period ending on May 7, 2021, and (ii) the original valuation amount equal to the per share initial reference price of $16.6582 multiplied by the 4,400,000 shares referenced by the Swap), became due from Glencore International to Citi.</footnote>
        <footnote id="F5">The Swap was held directly by Glencore International, and may be deemed to have been beneficially owned indirectly by Glencore plc. The Swap did not give the reporting persons direct or indirect voting, investment or dispositive control over any securities of the issuer, and accordingly, the reporting persons disclaim any beneficial ownership in the shares of common stock referenced by the swaps.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>GLENCORE INTERNATIONAL AG: By: /s/ John Burton; Name: John Burton; Title: Director</signatureName>
        <signatureDate>2021-05-10</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>GLENCORE INTERNATIONAL AG: By: /s/ Martin Haering; Name: Martin Haering; Title: Officer</signatureName>
        <signatureDate>2021-05-10</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>GLENCORE PLC: By: /s/ John Burton; Name: John Burton; Title: Company Secretary</signatureName>
        <signatureDate>2021-05-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
