<SEC-DOCUMENT>0001270606-26-000017.txt : 20260515
<SEC-HEADER>0001270606-26-000017.hdr.sgml : 20260515
<ACCEPTANCE-DATETIME>20260515180815
ACCESSION NUMBER:		0001270606-26-000017
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20260514
FILED AS OF DATE:		20260515
DATE AS OF CHANGE:		20260515

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BIEBER MICHAEL A
		CENTRAL INDEX KEY:			0001270606
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33076
		FILM NUMBER:		26990160

	MAIL ADDRESS:	
		STREET 1:		C/O WILLDAN GROUP INC.
		STREET 2:		2401 EAST KATELLA AVENUE, SUITE 300
		CITY:			ANAHEIM
		STATE:			CA
		ZIP:			92806

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Willdan Group, Inc.
		CENTRAL INDEX KEY:			0001370450
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ENGINEERING SERVICES [8711]
		ORGANIZATION NAME:           	07 Trade & Services
		EIN:				141951112
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0101

	BUSINESS ADDRESS:	
		STREET 1:		2401 EAST KATELLA AVENUE, SUITE 300
		CITY:			ANAHEIM
		STATE:			CA
		ZIP:			92806
		BUSINESS PHONE:		800-424-9144

	MAIL ADDRESS:	
		STREET 1:		2401 EAST KATELLA AVENUE, SUITE 300
		CITY:			ANAHEIM
		STATE:			CA
		ZIP:			92806
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4-05152026_100506.xml
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    <periodOfReport>2026-05-14</periodOfReport>

    <issuer>
        <issuerCik>0001370450</issuerCik>
        <issuerName>Willdan Group, Inc.</issuerName>
        <issuerTradingSymbol>WLDN</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

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            <rptOwnerName>BIEBER MICHAEL A</rptOwnerName>
        </reportingOwnerId>
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            <rptOwnerStreet1>2401 EAST KATELLA AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 300</rptOwnerStreet2>
            <rptOwnerCity>ANAHEIM</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92806</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>PRESIDENT AND CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
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                <value>Common Stock</value>
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                <transactionCode>M</transactionCode>
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            <transactionAmounts>
                <transactionShares>
                    <value>40009</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16.27</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
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                    <footnoteId id="F1"/>
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                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2026-05-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7956</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>92.65</value>
                    <footnoteId id="F4"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>249801</value>
                    <footnoteId id="F1"/>
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                <directOrIndirectOwnership>
                    <value>D</value>
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                    <value></value>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2026-05-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>276</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>93.74</value>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                <sharesOwnedFollowingTransaction>
                    <value>249525</value>
                    <footnoteId id="F1"/>
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                <directOrIndirectOwnership>
                    <value>D</value>
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                <natureOfOwnership>
                    <value></value>
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            </ownershipNature>
        </nonDerivativeTransaction>
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    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>16.27</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2026-05-14</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>40009</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2017-11-03</value>
                <footnoteId id="F6"/>
            </exerciseDate>
            <expirationDate>
                <value>2026-11-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>40009</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
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                    <value>0</value>
                </sharesOwnedFollowingTransaction>
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                </natureOfOwnership>
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        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options (Right to Buy)</value>
            </securityTitle>
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            <transactionDate>
                <value>2026-05-14</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                    <value>16667</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2018-03-08</value>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <value>2027-03-08</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>16667</value>
                </underlyingSecurityShares>
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                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
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                <natureOfOwnership>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Includes (i) 18,000 shares of restricted stock units that vest in three substantially equal installments on each of March 3, 2027, March 3, 2028 and March 3, 2029, (ii) 12,834 shares of restricted stock units that vest in two substantially equal installments on each of March 17, 2027 and March 17, 2028, and (iii) 5,834 shares of restricted stock units that vest on March 20, 2027, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date.</footnote>
        <footnote id="F2">The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $90.50 to $91.46, inclusive. The Reporting Person undertakes to provide to Willdan Group, Inc., any security holder of Willdan Group, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (2), footnote (3), footnote (4), and footnote (5).</footnote>
        <footnote id="F3">The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $91.50 to $92.49, inclusive.</footnote>
        <footnote id="F4">The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $92.50 to $93.41, inclusive.</footnote>
        <footnote id="F5">The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $93.62 to $93.99, inclusive.</footnote>
        <footnote id="F6">Stock options granted under the Willdan Group, Inc. Amended and Restated 2008 Performance Incentive Plan, which vested in three equal installments on each of November 3, 2017, November 3, 2018, and November 3, 2019.</footnote>
        <footnote id="F7">Stock options granted under the Willdan Group, Inc. Amended and Restated 2008 Performance Incentive Plan, which vested in three equal installments on each of March 8, 2018, March 8, 2019, and March 8, 2020.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Creighton K. Early, Attorney-in-fact for Michael A. Bieber</signatureName>
        <signatureDate>2026-05-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
