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<SEC-DOCUMENT>0000950005-09-000346.txt : 20091217
<SEC-HEADER>0000950005-09-000346.hdr.sgml : 20091217
<ACCEPTANCE-DATETIME>20091217195903
ACCESSION NUMBER:		0000950005-09-000346
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091215
FILED AS OF DATE:		20091217
DATE AS OF CHANGE:		20091217

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MV MANAGEMENT IX LLC
		CENTRAL INDEX KEY:			0001120126
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33041
		FILM NUMBER:		091248396

	BUSINESS ADDRESS:	
		STREET 1:		3000 SAND HILL ROAD
		STREET 2:		BLDG 3 SUITE 100
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MENLO VENTURES IX LP
		CENTRAL INDEX KEY:			0001120284
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33041
		FILM NUMBER:		091248395

	BUSINESS ADDRESS:	
		STREET 1:		3000 SAND HILL RD
		STREET 2:		BLDG 4 SUITE 100
		CITY:			MENLOPARK
		STATE:			CA
		ZIP:			94025

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ACME PACKET INC
		CENTRAL INDEX KEY:			0001130258
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER COMMUNICATIONS EQUIPMENT [3576]
		IRS NUMBER:				043526641
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		71 THIRD AVENUE
		CITY:			BURLINGTON
		STATE:			MA
		ZIP:			01803
		BUSINESS PHONE:		781-328-4400

	MAIL ADDRESS:	
		STREET 1:		71 THIRD AVENUE
		CITY:			BURLINGTON
		STATE:			MA
		ZIP:			01803

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PRIMARY NETWORKS INC
		DATE OF NAME CHANGE:	20001219

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MMEF IX LP
		CENTRAL INDEX KEY:			0001131824

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33041
		FILM NUMBER:		091248392

	BUSINESS ADDRESS:	
		STREET 1:		3000 SAND HILL ROAD BUILDING FOUR
		STREET 2:		SUITE 100
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025
		BUSINESS PHONE:		6508548540

	MAIL ADDRESS:	
		STREET 1:		300 SAND HILL ROAD, BUILDING 4,
		STREET 2:		SUITE 100
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MENLO ENTREPRENEURS FUND IX LP
		CENTRAL INDEX KEY:			0001131886
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33041
		FILM NUMBER:		091248394

	BUSINESS ADDRESS:	
		STREET 1:		3000 SAND HILL ROAD BUILDING FOUR
		STREET 2:		SUITE 100
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025
		BUSINESS PHONE:		6508548540

	MAIL ADDRESS:	
		STREET 1:		3000 SAND HILL ROAD, BUILDING 4
		STREET 2:		SUITE 100
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MENLO ENTREPRENEURS FUND IX A LP
		CENTRAL INDEX KEY:			0001230036
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33041
		FILM NUMBER:		091248393

	BUSINESS ADDRESS:	
		STREET 1:		3000 SAND HILL RD
		STREET 2:		BLDG 4 STE 100
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025
		BUSINESS PHONE:		4158548540

	MAIL ADDRESS:	
		STREET 1:		3000 SAND HILL RD
		STREET 2:		BLDG 4 STE 100
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025
</SEC-HEADER>
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<SEQUENCE>1
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<DESCRIPTION>PRIMARY DOCUMENT
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    <documentType>4</documentType>

    <periodOfReport>2009-12-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001130258</issuerCik>
        <issuerName>ACME PACKET INC</issuerName>
        <issuerTradingSymbol>APKT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001120126</rptOwnerCik>
            <rptOwnerName>MV MANAGEMENT IX LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3000 SAND HILL ROAD</rptOwnerStreet1>
            <rptOwnerStreet2>BUILDING 4 SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
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    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001120284</rptOwnerCik>
            <rptOwnerName>MENLO VENTURES IX LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3000 SAND HILL ROAD</rptOwnerStreet1>
            <rptOwnerStreet2>BUILDING 4 SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
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    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001131886</rptOwnerCik>
            <rptOwnerName>MENLO ENTREPRENEURS FUND IX LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3000 SAND HILL ROAD, BUILDING 4</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
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            <isOther>0</isOther>
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    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001230036</rptOwnerCik>
            <rptOwnerName>MENLO ENTREPRENEURS FUND IX A LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3000 SAND HILL RD</rptOwnerStreet1>
            <rptOwnerStreet2>BLDG 4 STE 100</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001131824</rptOwnerCik>
            <rptOwnerName>MMEF IX LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>300 SAND HILL ROAD, BUILDING 4,</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 100</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</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>2009-12-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>13048127</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-12-15</value>
            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>428567</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F6"/>
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            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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            <transactionDate>
                <value>2009-12-15</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
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                <value></value>
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            <transactionAmounts>
                <transactionShares>
                    <value>52392</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
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                <directOrIndirectOwnership>
                    <value>I</value>
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                <natureOfOwnership>
                    <value>See Footnote</value>
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                    <footnoteId id="F6"/>
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                <value>Common Stock</value>
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                <value>2009-12-15</value>
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                <value></value>
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                <transactionShares>
                    <value>235540</value>
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                <directOrIndirectOwnership>
                    <value>I</value>
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                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F5"/>
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        </nonDerivativeTransaction>
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    <footnotes>
        <footnote id="F1">Explanation of Code J:  Pro rate in kind distribution without consideration by Menlo Ventures IX, L.P., Menlo Entrepreneurs Fund IX, L.P., Menlo Entrepreneurs Fund IX(A), L.P. and MMEF IX, L.P. to all their partners, including MV Management IX, LLC, which in turn distributed pro rate in kind and without consideration all 137,646 shares it received to its members.</footnote>
        <footnote id="F2">These shares are owned directly by Menlo Ventures IX, L.P. (&quot;Menlo IX&quot;), of which MV Management IX, L.L.C. (&quot;MVM-IX&quot;) is the sole general partner and exercises voting and investment power over these shares. Menlo IX, Menlo Entrepreneurs Fund IX, L.P. Menlo Entrepreneurs IX(A), L.P. and MMEF IX L.P. may be deemed to be a member of a Section 13(d) &quot;group.&quot;  Menlo Entrepreneurs Fund IX, L.P., Menlo Entrepreneurs Fund IX(A), L.P. and MMEF IX, L.P. disclose the existence of such group and disclaim beneficial ownership of any shares by Menlo IX.</footnote>
        <footnote id="F3">These shares are owned directly by Menlo Entrepreneurs Fund IX, L.P., of which MVM-IX is the sole general partner and exercises voting and investment power over these shares. Menlo IX, Menlo Entrepreneurs Fund IX, L.P. Menlo Entrepreneurs IX(A), L.P. and MMEF IX L.P. may be deemed to be a member of a Section 13(d) &quot;group.&quot;  Menlo IX, Menlo Entrepreneurs Fund IX(A), L.P. and MMEF IX, L.P. disclose the existence of such group and disclaim beneficial ownership of any shares by Menlo Entrepreneurs Fund IX, L.P.</footnote>
        <footnote id="F4">These shares are owned directly by Menlo Entrepreneurs Fund IX(A), L.P., of which MVM-IX is the sole general partner and exercises voting and investment power over these shares. Menlo IX, Menlo Entrepreneurs Fund IX, L.P., Menlo Entrepreneurs IX(A), L.P. and MMEF IX L.P. may be deemed to be a member of a Section 13(d) &quot;group.&quot; Menlo Entrepreneurs Fund IX, L.P., Menlo IX and MMEF IX, L.P. disclose the existence of such group and disclaim beneficial ownership of any shares held by Menlo Entrepreneurs Fund IX(A), L.P.</footnote>
        <footnote id="F5">These shares are owned directly by MMEF IX, L.P., of which MVM-IX is the sole general partner and exercises voting and investment power over these shares. Menlo Ventures IX, L.P., Menlo Entrepreneurs IX, L.P. Menlo Entrepreneurs IX(A), L.P. and MMEF IX L.P. may be deemed to be a member of a Section 13(d) &quot;group.&quot; Menlo Ventures IX, L.P., Menlo Entrepreneurs Fund IX, L.P. and Menlo Entrepreneurs Fund IX(A), L.P. disclose the existence of such group and disclaim beneficial ownership of any shares held by MMEF IX, L.P.</footnote>
        <footnote id="F6">The managing members of MVM-IX are John W. Jarve, H.D. Montgomery, Douglas C. Carlisle, Sonja H. Perkins, Mark A. Siegel, Kenneth H. Calhoun, Arvind Purushotham, Pravin A. Vazirani and Shawn T. Carolan.  The reporting person and its managing members disclaim beneficial ownership of these securities, except to the extent of their respective proportionate pecuniary interest therein and this report shall not be deemed as admission that the reporting person is the beneficial owner of such securities for Section 16 or any other purpose.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>MV Management IX, L.L.C.  /s/ Sonja H. Perkins, Managing Member</signatureName>
        <signatureDate>2009-12-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Menlo Ventures IX, L.P. By: MV Management IX, L.L.C. Its General Partner  /s/ Sonja H. Perkins, Managing Member</signatureName>
        <signatureDate>2009-12-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Menlo Entrepreneurs Fund IX, L.P. By: MV Management IX, L.L.C. Its General Partner  /s/ Sonja H. Perkins, Managing Member</signatureName>
        <signatureDate>2009-12-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Menlo Entrepreneurs Fund IX(A), L.P. By: MV Management IX, L.L.C. Its General Partner  /s/ Sonja H. Perkins, Managing Member</signatureName>
        <signatureDate>2009-12-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>MMEF IX, L.P. By: MV Management IX, L.L.C. Its General Partner  /s/ Sonja H. Perkins, Managing Member</signatureName>
        <signatureDate>2009-12-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Menlo Entrepreneurs Fund IX, L.P. By: MV Management IX, L.L.C. Its General Partner  /s/ John W. Jarve, Managing Member</signatureName>
        <signatureDate>2009-12-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Menlo Entrepreneurs Fund IX(A), L.P. By: MV Management IX, L.L.C. Its General Partner  /s/ John W. Jarve, Managing Member</signatureName>
        <signatureDate>2009-12-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>MMEF IX, L.P. By: MV Management IX, L.L.C. Its General Partner  /s/ John W. Jarve, Managing Member</signatureName>
        <signatureDate>2009-12-15</signatureDate>
    </ownerSignature>
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-----END PRIVACY-ENHANCED MESSAGE-----