-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 O19r2BtMqXey1lNq6m/vYYOrIoilo5i7G+e3kd4UgzvSEpnYKKBOJt9wou1MOuku
 ElcTmO12J91arokxPdWJIw==

<SEC-DOCUMENT>0001181431-09-013225.txt : 20090303
<SEC-HEADER>0001181431-09-013225.hdr.sgml : 20090303
<ACCEPTANCE-DATETIME>20090303193644
ACCESSION NUMBER:		0001181431-09-013225
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090227
FILED AS OF DATE:		20090303
DATE AS OF CHANGE:		20090303

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CO INVESTMENT 2000 FUND LP
		CENTRAL INDEX KEY:			0001113583

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653487

	BUSINESS ADDRESS:	
		STREET 1:		5 RADNOR CORPORATE CENTER
		STREET 2:		SUITE 555
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CROSS ATLANTIC CAPITAL PARTNERS II  INC
		CENTRAL INDEX KEY:			0001252434
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653488

	MAIL ADDRESS:	
		STREET 1:		100 MATSONFORD RD STE 555
		CITY:			REDMAR
		STATE:			PA
		ZIP:			19087

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			XATF MANAGEMENT II LP
		CENTRAL INDEX KEY:			0001254180
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653489

	MAIL ADDRESS:	
		STREET 1:		5 RADNOR CORPORATE CENTER
		STREET 2:		STE 555
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CROSS ATLANTIC TECHNOLOGY FUND L P
		CENTRAL INDEX KEY:			0001102188

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653492

	BUSINESS ADDRESS:	
		STREET 1:		100 MATSONFORD RD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087
		BUSINESS PHONE:		6109952650

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Rubicon Technology, Inc.
		CENTRAL INDEX KEY:			0001410172
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				364419301
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		9931 FRANKLIN AVENUE
		CITY:			FRANKLIN PARK
		STATE:			IL
		ZIP:			60131
		BUSINESS PHONE:		(847) 295-7000

	MAIL ADDRESS:	
		STREET 1:		9931 FRANKLIN AVENUE
		CITY:			FRANKLIN PARK
		STATE:			IL
		ZIP:			60131

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CROSS ATLANTIC TECHNOLOGY FUND II LP
		CENTRAL INDEX KEY:			0001165410
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653490

	BUSINESS ADDRESS:	
		STREET 1:		FIVE RADNOR CORPORATE CENTER SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087
		BUSINESS PHONE:		610 995 2650

	MAIL ADDRESS:	
		STREET 1:		5 RANDOR CORPORATE CENTER STE 555
		CITY:			RANDNOR
		STATE:			PA
		ZIP:			19087

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Co-Invest Capital Partners Inc
		CENTRAL INDEX KEY:			0001297591
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653485

	BUSINESS ADDRESS:	
		STREET 1:		5 RADNOR CORPORATE CENTER, SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087
		BUSINESS PHONE:		610-995-2650

	MAIL ADDRESS:	
		STREET 1:		5 RADNOR CORPORATE CENTER, SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Co-Invest Management LP
		CENTRAL INDEX KEY:			0001297592
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653486

	BUSINESS ADDRESS:	
		STREET 1:		5 RADNOR CORPORATE CENTER, SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087
		BUSINESS PHONE:		610-995-2650

	MAIL ADDRESS:	
		STREET 1:		5 RADNOR CORPORATE CENTER, SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Cross Atlantic Capital Partners, Inc.
		CENTRAL INDEX KEY:			0001418340
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653493

	BUSINESS ADDRESS:	
		STREET 1:		FIVE RADNOR CORPORATE CENTER, SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087
		BUSINESS PHONE:		(610) 995-2650

	MAIL ADDRESS:	
		STREET 1:		FIVE RADNOR CORPORATE CENTER, SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			XATF Management, L.P.
		CENTRAL INDEX KEY:			0001418345
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33834
		FILM NUMBER:		09653491

	BUSINESS ADDRESS:	
		STREET 1:		FIVE RADNOR CORPORATE CENTER, SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087
		BUSINESS PHONE:		(610) 995-2650

	MAIL ADDRESS:	
		STREET 1:		FIVE RADNOR CORPORATE CENTER, SUITE 555
		STREET 2:		100 MATSONFORD ROAD
		CITY:			RADNOR
		STATE:			PA
		ZIP:			19087
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd236106.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-02-27</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001410172</issuerCik>
        <issuerName>Rubicon Technology, Inc.</issuerName>
        <issuerTradingSymbol>RBCN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001418340</rptOwnerCik>
            <rptOwnerName>Cross Atlantic Capital Partners, Inc.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001102188</rptOwnerCik>
            <rptOwnerName>CROSS ATLANTIC TECHNOLOGY FUND L P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001418345</rptOwnerCik>
            <rptOwnerName>XATF Management, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001165410</rptOwnerCik>
            <rptOwnerName>CROSS ATLANTIC TECHNOLOGY FUND II LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001254180</rptOwnerCik>
            <rptOwnerName>XATF MANAGEMENT II LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001252434</rptOwnerCik>
            <rptOwnerName>CROSS ATLANTIC CAPITAL PARTNERS II  INC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001113583</rptOwnerCik>
            <rptOwnerName>CO INVESTMENT 2000 FUND LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001297592</rptOwnerCik>
            <rptOwnerName>Co-Invest Management LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001297591</rptOwnerCik>
            <rptOwnerName>Co-Invest Capital Partners Inc</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FIVE RADNOR CORPORATE CENTER, SUITE 555</rptOwnerStreet1>
            <rptOwnerStreet2>100 MATSONFORD ROAD</rptOwnerStreet2>
            <rptOwnerCity>RADNOR</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19087</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>4.01</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-02-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>13964</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2019-02-27</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>13964</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>13964</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Options vest at the rate of 25% of the total option grant at the end of each quarter of fiscal 2009 (March 31, 2009, June 30, 2009, September 30, 2009 and December 31, 2009).</footnote>
        <footnote id="F2">These options were granted to Donald R. Caldwell (?Caldwell?), a director of the Issuer, who is the owner and director of Cross Atlantic Capital Partners, Inc., which is the general partner of XATF Management L.P., which is the general partner of Cross Atlantic Technology Fund, L.P.  Caldwell is a director, shareholder and officer of Cross Atlantic Capital Partners II, Inc., which is the general partner of XATF Management II, L.P., which is the general partner of Cross Atlantic Technology Fund II. L.P.  Caldwell is a shareholder, director and officer of Co-Invest Capital Partners, Inc., which is the general partner of Co-Invest Management, L.P., which is the general partner of The Co-Investment 2000 Fund, L.P.  Cross Atlantic Technology Fund, L.P, Cross Atlantic Technology Fund, II, L.P. and The Co-Investment 2000 Fund, L.P. are collectively referred to as the ?Funds?. ( Continued footnote 3 ).</footnote>
        <footnote id="F3">Under the terms of the applicable partnership agreements of the Funds, Caldwell is deemed to hold these options for the benefit of the Funds, which are entitled to receive the net economic benefit of the options as a credit against the management fees owed by the funds to Cross Atlantic Capital Partners, Inc.  The Funds disclaim beneficial ownership of the options except to the extent of their pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Scott Glickson, attorney-in-fact</signatureName>
        <signatureDate>2009-03-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----