<SEC-DOCUMENT>0001193125-26-124360.txt : 20260325
<SEC-HEADER>0001193125-26-124360.hdr.sgml : 20260325
<ACCEPTANCE-DATETIME>20260325171407
ACCESSION NUMBER:		0001193125-26-124360
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250508
FILED AS OF DATE:		20260325
DATE AS OF CHANGE:		20260325

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BAYER RYAN
		CENTRAL INDEX KEY:			0001990270
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33225
		FILM NUMBER:		26793494

	MAIL ADDRESS:	
		STREET 1:		C/O GREAT LAKES DREDGE & DOCK CORP
		STREET 2:		9811 KATY FREEWAY, SUITE 1200
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77024

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Great Lakes Dredge & Dock CORP
		CENTRAL INDEX KEY:			0001372020
		STANDARD INDUSTRIAL CLASSIFICATION:	HEAVY CONSTRUCTION OTHER THAN BUILDING CONST - CONTRACTORS [1600]
		ORGANIZATION NAME:           	05 Real Estate & Construction
		EIN:				205336063
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		9811 KATY FREEWAY
		STREET 2:		SUITE 1200
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77024
		BUSINESS PHONE:		(346) 359-1010

	MAIL ADDRESS:	
		STREET 1:		9811 KATY FREEWAY
		STREET 2:		SUITE 1200
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77024

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Great Lakes Dredge & Dock Holdings Corp.
		DATE OF NAME CHANGE:	20060808
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>ownership.xml
<DESCRIPTION>4/A
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0609</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2025-05-08</periodOfReport>

    <dateOfOriginalSubmission>2025-05-12</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0001372020</issuerCik>
        <issuerName>Great Lakes Dredge &amp; Dock CORP</issuerName>
        <issuerTradingSymbol>GLDD</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001990270</rptOwnerCik>
            <rptOwnerName>BAYER RYAN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>C/O GREAT LAKES DREDGE &amp; DOCK CORP.</rptOwnerStreet1>
            <rptOwnerStreet2>9811 KATY FREEWAY, SUITE 1200</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77024</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>VP &amp; CAO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-05-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10126</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24574</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">This Form 4/A is being filed to correct an administrative error in the original Form 4 filed on May 12, 2025 in which the vesting date for the Restricted Stock Units was inadvertently reported as beginning on March 15, 2026. The correct vesting date begins on May 8, 2026.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Vivienne R. Schiffer, by Power of Attorney</signatureName>
        <signatureDate>2026-03-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
