<SEC-DOCUMENT>0000920371-16-000243.txt : 20160428
<SEC-HEADER>0000920371-16-000243.hdr.sgml : 20160428
<ACCEPTANCE-DATETIME>20160428191137
ACCESSION NUMBER:		0000920371-16-000243
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20160427
FILED AS OF DATE:		20160428
DATE AS OF CHANGE:		20160428

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SIMPSON MANUFACTURING CO INC /CA/
		CENTRAL INDEX KEY:			0000920371
		STANDARD INDUSTRIAL CLASSIFICATION:	CUTLERY, HANDTOOLS & GENERAL HARDWARE [3420]
		IRS NUMBER:				943196943
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		5956 W LAS POSITAS BLVD
		CITY:			PLEASANTON
		STATE:			CA
		ZIP:			94588
		BUSINESS PHONE:		9255609000

	MAIL ADDRESS:	
		STREET 1:		5956 W LAS POSITAS BLVD
		CITY:			PLEASANTON
		STATE:			CA
		ZIP:			94588

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Leung Sunny H
		CENTRAL INDEX KEY:			0001663072

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13429
		FILM NUMBER:		161601908

	MAIL ADDRESS:	
		STREET 1:		C/O SIMPSON MANUFACTURING CO., INC.
		STREET 2:		5956 W. LAS POSITAS BLVD.
		CITY:			PLEASANTON
		STATE:			CA
		ZIP:			94588
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_146188508432684.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-04-27</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000920371</issuerCik>
        <issuerName>SIMPSON MANUFACTURING CO INC /CA/</issuerName>
        <issuerTradingSymbol>SSD</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001663072</rptOwnerCik>
            <rptOwnerName>Leung Sunny H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5956 W. LAS POSITAS BLVD.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PLEASANTON</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94588</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock (RSUs awarded February 3, 2014)</value>
            </securityTitle>
            <transactionDate>
                <value>2016-04-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>484</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>38.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1447</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock (RSUs awarded February 6, 2013)</value>
            </securityTitle>
            <transactionDate>
                <value>2016-04-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>504</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>38.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>943</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock (RSUs awarded February 1, 2016)</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>967</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock (RSUs awarded February 2, 2015)</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>967</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>484</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>857</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Options on Common Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>29.66</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2012-02-03</value>
            </exerciseDate>
            <expirationDate>
                <value>2018-02-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>11000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Amount includes 1,447 shares of restricted stock units (RSUs) awarded on February 3, 2014. RSUs vest one fourth on each of the award date and the first, second and third anniversaries of the award date. The 1,447 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.</footnote>
        <footnote id="F2">Amount includes 943 shares of restricted stock units (RSUs) awarded on February 6, 2013. RSUs vest one fourth on each of the award date and the first, second and third anniversaries of the award date. The 943 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.</footnote>
        <footnote id="F3">Amount includes 967 shares of restricted stock units (RSUs) awarded on February 1, 2016. RSUs vest one fourth on each of the award date and the first, second and third anniversaries of the award date. The 967 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.</footnote>
        <footnote id="F4">Amount includes 967 shares of restricted stock units (RSUs) awarded on February 2, 2015. RSUs vest one fourth on each of the award date and the first, second and third anniversaries of the award date. The 967 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/SUNNY H. LEUNG</signatureName>
        <signatureDate>2016-04-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
