-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001209191-07-034237.txt : 20070531
<SEC-HEADER>0001209191-07-034237.hdr.sgml : 20070531
<ACCEPTANCE-DATETIME>20070531191922
ACCESSION NUMBER:		0001209191-07-034237
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070530
FILED AS OF DATE:		20070531
DATE AS OF CHANGE:		20070531

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WHEELER KURT
		CENTRAL INDEX KEY:			0001252525

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33484
		FILM NUMBER:		07892210

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		6502385000

	MAIL ADDRESS:	
		STREET 1:		801 GATEWAY BLVD
		STREET 2:		STE 410
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94080

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HENNER DENNIS
		CENTRAL INDEX KEY:			0001249153

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33484
		FILM NUMBER:		07892211

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		THE JOHN HANCOCK TOWER
		STREET 2:		200 CLARENDON STREET, 54TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GALAKATOS NICHOLAS
		CENTRAL INDEX KEY:			0001252522

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33484
		FILM NUMBER:		07892212

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		THE JOHN HANCOCK TOWER
		STREET 2:		200 CLARENDON STREET, 54TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SIMON NICHOLAS J III
		CENTRAL INDEX KEY:			0001221595

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33484
		FILM NUMBER:		07892213

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		THE JOHN HANCOCK TOWER
		STREET 2:		200 CLARENDON STREET, 54TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STEINMETZ MICHAEL
		CENTRAL INDEX KEY:			0001166285

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33484
		FILM NUMBER:		07892214

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		THE JOHN HANCOCK TOWER
		STREET 2:		200 CLARENDON STREET, 54TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GADICKE ANSBERT
		CENTRAL INDEX KEY:			0001134655

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33484
		FILM NUMBER:		07892215

	BUSINESS ADDRESS:	
		STREET 1:		ONE CAMBRIDGE CENTER
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		THE JOHN HANCOCK TOWER
		STREET 2:		200 CLARENDON STREET, 54TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			EVNIN LUKE
		CENTRAL INDEX KEY:			0001134657

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33484
		FILM NUMBER:		07892216

	BUSINESS ADDRESS:	
		STREET 1:		ONE CAMBRIDGE CENTER
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		6174259200

	MAIL ADDRESS:	
		STREET 1:		THE JOHN HANCOCK TOWER
		STREET 2:		200 CLARENDON STREET, 54TH STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HELICOS BIOSCIENCES CORP
		CENTRAL INDEX KEY:			0001274563
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				050587367

	BUSINESS ADDRESS:	
		STREET 1:		ONE KENDALL SQUARE
		STREET 2:		BUILDING 700
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		617-649-0540

	MAIL ADDRESS:	
		STREET 1:		ONE KENDALL SQUARE
		STREET 2:		BUILDING 700
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
</SEC-HEADER>
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<DESCRIPTION>MAIN DOCUMENT DESCRIPTION
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    <documentType>4</documentType>

    <periodOfReport>2007-05-30</periodOfReport>

    <issuer>
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        <issuerName>HELICOS BIOSCIENCES CORP</issuerName>
        <issuerTradingSymbol>HLCS</issuerTradingSymbol>
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    <reportingOwner>
        <reportingOwnerId>
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            <rptOwnerName>EVNIN LUKE</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST., 54TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
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    <reportingOwner>
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            <rptOwnerName>GADICKE ANSBERT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST., 54TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001166285</rptOwnerCik>
            <rptOwnerName>STEINMETZ MICHAEL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST., 54TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
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    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001221595</rptOwnerCik>
            <rptOwnerName>SIMON NICHOLAS J III</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST., 54TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001252522</rptOwnerCik>
            <rptOwnerName>GALAKATOS NICHOLAS</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST., 54TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001249153</rptOwnerCik>
            <rptOwnerName>HENNER DENNIS</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST., 54TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001252525</rptOwnerCik>
            <rptOwnerName>WHEELER KURT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MPM ASSET MANAGEMENT</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST., 54TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-05-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1162836</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1162836</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-05-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1491600</value>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2654436</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-05-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>333333</value>
                    <footnoteId id="F5"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2987769</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Series A Redeemable Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-05-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5232778</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F7"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1162836</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Series B Redeemable Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-05-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6712209</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F7"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F7"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1491600</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
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    <footnotes>
        <footnote id="F1">The shares are held as follows:   65,084 shares by MPM BioVentures III, L.P., (&quot;BV III&quot;), 967,974 shares by MPM BioVentures III-QP, L.P. (&quot;BV III QP&quot;), 81,805 shares held by MPM BioVentures III GmbH &amp; Co. Beteiligungs KG (&quot;BV KG&quot;), 29,232 shares by MPM BioVentures III Parallel Fund, L.P. (&quot;BV III PF&quot;) and 18,741 shares held by MPM Asset Management Investors 2003 BVIII LLC (&quot;AM BV III&quot;).   MPM BioVentures III GP, L.P. (&quot;BV III GP&quot;) and MPM BioVentures III LLC (&quot;BV III LLC&quot;) are the direct and indirect general partners of BV III, BV III QP, BV III PF and BV KG.  Luke Evnin, Ansbert Gadicke, Michael Steinmetz, Nicholas Galakatos, Dennis Henner, Nicholas Simon, III and Kurt Wheeler are members of BV III LLC and AM BV III.  Each member of the group disclaims beneficial ownership of all such shares except to the extent of their respective proportionate pecuniary interests therein.</footnote>
        <footnote id="F2">Each share of preferred stock automatically converted on a 1 for 4.5 basis into shares of Common Stock upon the closing of the Issuer's initial public offering.</footnote>
        <footnote id="F3">The shares are held as follows:  83,484 by BV III, 1,241,643 by BV III QP, 104,934 by BV KG, 37,499 by BV III PF and 24,040 by AM BV III.  Each member of the group disclaims beneficial ownership of all such shares except to the extent of their respective proportionate pecuniary interests therein.</footnote>
        <footnote id="F4">The shares are held as follows:  148,568 by BV III, 2,209,617 by BV III QP, 186,739 by BV KG, 66,731 by BV III PF and 42,781 by AM BV III.  Each member of the group disclaims beneficial ownership of all such shares except to the extent of their respective proportionate pecuniary interests therein.</footnote>
        <footnote id="F5">The shares were purchased as follows:  18,657 by BV III, 277,474 by BV III QP, 23,450 by BV KG, 8,380 by BV III PF and 5,372 by AM BV III.  Each member of the group disclaims beneficial ownership of all such shares except to the extent of their respective proportionate pecuniary interests therein.</footnote>
        <footnote id="F6">The shares are held as follows:  167,225 by BV III, 2,487,091 by BV III QP, 210,189 by BV KG, 75,111 by BV III PF and 48,153 by AM BV III.  Each member of the group disclaims beneficial ownership of all such shares except to the extent of their respective proportionate pecuniary interests therein.</footnote>
        <footnote id="F7">These secutiries are preferred stock of the Issuer and do not have an expiration date.  These securities automatically converted into shares of common stock upon the closing of the Issuer's initial public offering.</footnote>
        <footnote id="F8">No securities owned.</footnote>
    </footnotes>

    <remarks>See Form 4 for MPM BioVentures III-QP, L.P. for additional members of the joint filing.</remarks>

    <ownerSignature>
        <signatureName>/s/ Luke Evnin</signatureName>
        <signatureDate>2007-05-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Ansbert Gadicke</signatureName>
        <signatureDate>2007-05-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Michael Steinmetz</signatureName>
        <signatureDate>2007-05-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Nicholas J. Simon, III</signatureName>
        <signatureDate>2007-05-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Nicholas Galakatos</signatureName>
        <signatureDate>2007-05-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Dennis Henner</signatureName>
        <signatureDate>2007-05-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Kurt Wheeler</signatureName>
        <signatureDate>2007-05-31</signatureDate>
    </ownerSignature>
</ownershipDocument>
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-----END PRIVACY-ENHANCED MESSAGE-----