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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 HRtPvn8sUYnIUPmwLeGWeYqeWyWfumAH+zS3pAPzL7mWGajEDiXEAe4mQ6QO+9vZ
 T2tDJjswKgp3UCksRcgzOQ==

<SEC-DOCUMENT>0001181431-10-057060.txt : 20101122
<SEC-HEADER>0001181431-10-057060.hdr.sgml : 20101122
<ACCEPTANCE-DATETIME>20101122162008
ACCESSION NUMBER:		0001181431-10-057060
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101118
FILED AS OF DATE:		20101122
DATE AS OF CHANGE:		20101122

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Sherif Tarek
		CENTRAL INDEX KEY:			0001466275

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34387
		FILM NUMBER:		101208975

	MAIL ADDRESS:	
		STREET 1:		C/O MEDIDATA SOLUTIONS, INC.
		STREET 2:		79 FIFTH AVENUE, 8TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10003

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Medidata Solutions, Inc.
		CENTRAL INDEX KEY:			0001453814
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				522319066
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		79 FIFTH AVENUE, 8TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10003
		BUSINESS PHONE:		212.918.1800

	MAIL ADDRESS:	
		STREET 1:		79 FIFTH AVENUE, 8TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10003
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd291767.xml
<DESCRIPTION>FORM 4 - TAREK SHERIF
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-11-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001453814</issuerCik>
        <issuerName>Medidata Solutions, Inc.</issuerName>
        <issuerTradingSymbol>MDSO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001466275</rptOwnerCik>
            <rptOwnerName>Sherif Tarek</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MEDIDATA SOLUTIONS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>79 FIFTH AVENUE, 8TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10003</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman &amp; CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1147258</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>14998</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.2635</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1132260</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 11, 2010.</footnote>
        <footnote id="F2">Such transaction was executed in multiple trades at prices ranging from $19.05 to $19.485. The price reported reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Michael I. Otner, Attorney-in-Fact</signatureName>
        <signatureDate>2010-11-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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