-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 GSNshXJroivvsoXDSTAt72eR3O5d0OotoXU7hPdOIr+OyuevHEpy9O1s7jPVsbsg
 n0n62z7wYlR64ttYqTBnpw==

<SEC-DOCUMENT>0001181431-07-045594.txt : 20070713
<SEC-HEADER>0001181431-07-045594.hdr.sgml : 20070713
<ACCEPTANCE-DATETIME>20070713163002
ACCESSION NUMBER:		0001181431-07-045594
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070711
FILED AS OF DATE:		20070713
DATE AS OF CHANGE:		20070713

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NETSCOUT SYSTEMS INC
		CENTRAL INDEX KEY:			0001078075
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER INTEGRATED SYSTEMS DESIGN [7373]
		IRS NUMBER:				042837575
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		4 TECHNOLOGY PARK DR
		CITY:			WESTFORD
		STATE:			MA
		ZIP:			01886
		BUSINESS PHONE:		9786144000

	MAIL ADDRESS:	
		STREET 1:		4 TECHNOLOGY PARK DRIVE
		CITY:			WESTFORD
		STATE:			MA
		ZIP:			01886

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			TA ASSOCIATES INC
		CENTRAL INDEX KEY:			0001034569

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26251
		FILM NUMBER:		07978934

	BUSINESS ADDRESS:	
		STREET 1:		125 HIGH STREET
		STREET 2:		SUITE 2500
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
		BUSINESS PHONE:		6175746781

	MAIL ADDRESS:	
		STREET 1:		125 HIGH STREET
		STREET 2:		SUITE 2500
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd165914.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-07-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001078075</issuerCik>
        <issuerName>NETSCOUT SYSTEMS INC</issuerName>
        <issuerTradingSymbol>NTCT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001034569</rptOwnerCik>
            <rptOwnerName>TA ASSOCIATES INC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>JOHN HANCOCK TOWER</rptOwnerStreet1>
            <rptOwnerStreet2>200 CLARENDON ST, 56TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>See General Remarks</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-07-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>93800</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>8.6546</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3311105</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes 1&amp;2</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1008</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person may be deemed to have an indirect pecuniary interest as the General Partner of TA Associates AAP III Partners and as the Manager of TA Associates VIII LLC, TA Executives Fund LLC and TA Investors LLC.  The reporting person disclaims beneficial ownership  of such shares because the reporting person 's indirect pecuniary interest is subject to indeterminable future events.</footnote>
        <footnote id="F2">The reporting person is the indirect beneficial owner of the following shares of Common Stock: (i) 2,516,162 owned by TA/Advent VIII L.P.; (ii) 658,066 shares owned by Advent Atlantic and Pacific III L.P.; (iii) 66,684 shares owned by TA Executives Fund LLC.; and (iv) 70,193 shares owned by TA Investors LLC.  TA Associates VIII LLC is the General Partner of TA/Advent VIII L.P.  TA Associates AAP III Partners is the General Partner of Advent Atlantic and Pacific III L.P.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>TA Associates, Inc.</signatureName>
        <signatureDate>2007-07-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>By: Thomas P. Alber, Chief Financial Officer</signatureName>
        <signatureDate>2007-07-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----