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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001063083-10-000017.txt : 20101029
<SEC-HEADER>0001063083-10-000017.hdr.sgml : 20101029
<ACCEPTANCE-DATETIME>20101029164351
ACCESSION NUMBER:		0001063083-10-000017
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101027
FILED AS OF DATE:		20101029
DATE AS OF CHANGE:		20101029

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RYAN PAUL R
		CENTRAL INDEX KEY:			0001063083
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26068
		FILM NUMBER:		101152370

	MAIL ADDRESS:	
		STREET 1:		C/O ACACIA RESEARCH CORPORATION
		STREET 2:		500 NEWPORT CENTER DRIVE, 7TH FLOOR
		CITY:			NEWPORT BEACH
		STATE:			CA
		ZIP:			92660

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ACACIA RESEARCH CORP
		CENTRAL INDEX KEY:			0000934549
		STANDARD INDUSTRIAL CLASSIFICATION:	PATENT OWNERS & LESSORS [6794]
		IRS NUMBER:				954405754
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		500 NEWPORT CENTER DRIVE
		STREET 2:		7TH FLOOR
		CITY:			NEWPORT BEACH
		STATE:			CA
		ZIP:			92660
		BUSINESS PHONE:		9494808300

	MAIL ADDRESS:	
		STREET 1:		500 NEWPORT CENTER DRIVE
		STREET 2:		#
		CITY:			NEWPORT BEACH
		STATE:			CA
		ZIP:			92660
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
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                    <value>91667</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>91667</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.14</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-10-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>45800</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-12-31</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-10-19</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>45800</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>45867</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.14</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-10-29</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>45867</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-12-31</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-10-19</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>45867</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The price reported is the average price for shares sold between $26.79 and $26.995 per share.</footnote>
        <footnote id="F2">The price reported is the average price for shares sold between $27.00 and $27.20 per share.</footnote>
        <footnote id="F3">The price reported is the average price for shares sold between $27.21and $27.41 per share.</footnote>
        <footnote id="F4">The price reported is the average price for shares sold between $26.00 and $26.25 per share.</footnote>
        <footnote id="F5">The price reported is the average price for shares sold between $26.26 and $26.51 per share.</footnote>
        <footnote id="F6">The price reported is the average price for shares sold between $26.52 and 26.70 per share.</footnote>
        <footnote id="F7">The price reported is the average price for shares sold between $26.76 and $27.00 per share.</footnote>
        <footnote id="F8">The price reported is the average price for shares sold between $27.01 and $27.21 per share.</footnote>
        <footnote id="F9">The price reported is the average price for shares sold between $27.27 and $27.36 per share.</footnote>
        <footnote id="F10">The price reported is the average price for shares sold between $27.60 and $27.76 per share.</footnote>
        <footnote id="F11">The price reported is the average price for shares sold between  $25.75 and $25.92 per share.</footnote>
        <footnote id="F12">The price reported is the average price for shares sold between $25.96 and $26.1613 per share.</footnote>
        <footnote id="F13">The price reported is the average price for shares sold between $26.19 and $26.39 per share.</footnote>
        <footnote id="F14">The price reported is the average price for shares sold between $26.40 and $26.50 per share.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Paul R. Ryan</signatureName>
        <signatureDate>2010-10-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----