<SEC-DOCUMENT>0001292814-26-001751.txt : 20260325
<SEC-HEADER>0001292814-26-001751.hdr.sgml : 20260325
<ACCEPTANCE-DATETIME>20260325151647
ACCESSION NUMBER:		0001292814-26-001751
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260320
FILED AS OF DATE:		20260325
DATE AS OF CHANGE:		20260325

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Johannpeter Guilherme Chagas Gerdau
		CENTRAL INDEX KEY:			0002121459
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14878
		FILM NUMBER:		26791764

	MAIL ADDRESS:	
		ADDRESS IS A NON US LOCATION: 	YES
		STREET 1:		AVENUE DOUTORA RUTH DE CARDOSO, 8501
		STREET 2:		8TH FLOOR, PINHEIROS
		CITY:			SAO PAULO
		NON US STATE TERRITORY:  	SAO PAULO
		PROVINCE COUNTRY:   	D5
		ZIP:			05425-070

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GERDAU S.A.
		CENTRAL INDEX KEY:			0001073404
		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL WORKS, BLAST FURNACES & ROLLING & FINISHING MILLS [3310]
		ORGANIZATION NAME:           	04 Manufacturing
		EIN:				000000000
		STATE OF INCORPORATION:			D5
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		ADDRESS IS A NON US LOCATION: 	YES
		STREET 1:		AV DOUTORA RUTH CARDOSO, 8,501
		STREET 2:		8TH FLOOR
		CITY:			SAO PAULO, SP
		PROVINCE COUNTRY:   	D5
		ZIP:			05425-070
		BUSINESS PHONE:		011-55-51-3323-2703

	MAIL ADDRESS:	
		ADDRESS IS A NON US LOCATION: 	YES
		STREET 1:		AV DOUTORA RUTH CARDOSO, 8,501
		STREET 2:		8TH FLOOR
		CITY:			SAO PAULO, SP
		PROVINCE COUNTRY:   	D5
		ZIP:			05425-070

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	GERDAU SA
		DATE OF NAME CHANGE:	19981112
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>ownership.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0609</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2026-03-20</periodOfReport>

    <dateOfOriginalSubmission>2026-03-24</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001073404</issuerCik>
        <issuerName>GERDAU S.A.</issuerName>
        <issuerTradingSymbol>GGB</issuerTradingSymbol>
        <issuerForeignTradingSymbol>GGBR</issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002121459</rptOwnerCik>
            <rptOwnerName>Johannpeter Guilherme Chagas Gerdau</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>true</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>AVENUE DOUTORA RUTH DE CARDOSO, 8501</rptOwnerStreet1>
            <rptOwnerStreet2>8TH FLOOR, PINHEIROS</rptOwnerStreet2>
            <rptOwnerCity>SAO PAULO</rptOwnerCity>
            <rptOwnerNonUSStateTerritory>SAO PAULO</rptOwnerNonUSStateTerritory>
            <rptOwnerCountry>D5</rptOwnerCountry>
            <rptOwnerZipCode>05425-070</rptOwnerZipCode>
            <rptOwnerStateDescription>BRAZIL</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Vice-Chairman of Board</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Preferred shares</value>
            </securityTitle>
            <transactionDate>
                <value>2026-03-20</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>85607</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.29</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common shares</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>702952615</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Remarks</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.69</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2027-02-12</value>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2027-02-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Preferred shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>106519</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>106519</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.47</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2028-02-12</value>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2028-02-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Preferred shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>116745</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>116745</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.95</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2029-02-12</value>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <value>2029-02-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Preferred shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>105670</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>105670</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The price is denominated in Brazilian reais and has been translated into U.S. dollars at the March 20, 2026 selling rate of R$5.2800 per US$1.00, as reported by the Central Bank of Brazil.</footnote>
        <footnote id="F2">See remarks below.</footnote>
        <footnote id="F3">Restricted stock units vest on February 12, 2027.</footnote>
        <footnote id="F4">Restricted stock units vest on February 12, 2028.</footnote>
        <footnote id="F5">Restricted stock units vest on February 12, 2029.</footnote>
    </footnotes>

    <remarks>The Reporting Person has a 25% interest in Frepar Participacoes S.A.. Frepar Participacoes S.A. holds a 25% equity interest in INDAC - Investimentos e Participacoes S.A. INDAC owns 57% of Grupo Gerdau Empreendimentos Ltda. INDAC holds 100% of Acoter Participacoes Ltda. Acoter Participacoes Ltda. owns the remaining 43% of Grupo Gerdau Empreendimentos Ltda. Grupo Gerdau Empreendimentos Ltda. together with INDAC hold 27,58% of Gerdau Metalurgica S.A.'s total shares. Gerdau Metalurgica S.A. is the direct controlling shareholder of the issuer, owning 35,56% of its shares. The Reporting Person disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, and the inclusion of these shares in this report shall not be deemed an admission of beneficial ownership of all of the reported shares for purposes of Section 16 or for any other purpose.</remarks>

    <ownerSignature>
        <signatureName>/s/ Guilherme Chagas Gerdau Johannpeter</signatureName>
        <signatureDate>2026-03-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
