<SEC-DOCUMENT>0000920371-15-000026.txt : 20150203
<SEC-HEADER>0000920371-15-000026.hdr.sgml : 20150203
<ACCEPTANCE-DATETIME>20150203180447
ACCESSION NUMBER:		0000920371-15-000026
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20150202
FILED AS OF DATE:		20150203
DATE AS OF CHANGE:		20150203

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:			Arevalo Ricardo M
		CENTRAL INDEX KEY:			0001601717

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13429
		FILM NUMBER:		15572704

	MAIL ADDRESS:	
		STREET 1:		5956 W. LAS POSITAS BLVD.
		CITY:			PLEASANTON
		STATE:			CA
		ZIP:			94588
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_142300467582773.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2015-02-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001601717</rptOwnerCik>
            <rptOwnerName>Arevalo Ricardo M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5956 W. LAS POSITAS</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>COO, Simpson Strong-Tie</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock (RSUs awarded February 2, 2015)</value>
            </securityTitle>
            <transactionDate>
                <value>2015-02-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2170</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>32.64</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2170</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock (RSUs awarded February 3, 2014)</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3210</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock (RSUs awarded February 6, 2013)</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4806</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock (RSUs awarded January 30, 2012)</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3149</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Options on Common Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>29.66</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2011-03-03</value>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-02-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Options on Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>6251.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6251</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Amount includes 2,170 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 2,170 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 3,210 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 3,210 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 4,806 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 4,806 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 3,149 shares of restricted stock units (RSUs) awarded on January 30, 2012. RSUs vest one fourth on each of the award date and the first, second and third anniversaries of the award date. The 3,149 shares are net of the number of shares expected to be withheld to cover the estimated income taxes due on vesting.</footnote>
        <footnote id="F5">This date represents the date of the first monthly vesting period. This option vests equally over 48 months beginning with the date of grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/RICARDO M. AREVALO</signatureName>
        <signatureDate>2015-02-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
