-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001140361-10-041626.txt : 20101019
<SEC-HEADER>0001140361-10-041626.hdr.sgml : 20101019
<ACCEPTANCE-DATETIME>20101019171418
ACCESSION NUMBER:		0001140361-10-041626
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101015
FILED AS OF DATE:		20101019
DATE AS OF CHANGE:		20101019

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MCDERMOTT CHARLES J
		CENTRAL INDEX KEY:			0001241877

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130996

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			JAMES WILLIAM E
		CENTRAL INDEX KEY:			0001218568

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130997

	MAIL ADDRESS:	
		STREET 1:		C/O ROCKPORT CAPITAL PARTNERS LLC
		STREET 2:		160 GFEDERAL STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110-1776

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROCKPORT CAPITAL I LLC
		CENTRAL INDEX KEY:			0001236155
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130991

	MAIL ADDRESS:	
		STREET 1:		C/O KATHERINE COMER, MINTZ, LEVIN...
		STREET 2:		ONE FINANCIAL CENTER
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02111

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ELLIS ALEXANDER III
		CENTRAL INDEX KEY:			0001228600

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130993

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Prend David J
		CENTRAL INDEX KEY:			0001418018

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130995

	MAIL ADDRESS:	
		STREET 1:		ROCKPORT CAPITAL PARTNERS
		STREET 2:		160 FEDERAL STREET, 18TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			James Janet Burrows
		CENTRAL INDEX KEY:			0001422108

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130998

	MAIL ADDRESS:	
		STREET 1:		160 FEDERAL STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Wilson Stoddard Moran
		CENTRAL INDEX KEY:			0001422111

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130994

	MAIL ADDRESS:	
		STREET 1:		160 FEDERAL STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CLEAN DIESEL TECHNOLOGIES INC
		CENTRAL INDEX KEY:			0000949428
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL INORGANIC CHEMICALS [2810]
		IRS NUMBER:				061393453
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		10 MIDDLE STREET
		STREET 2:		SUITE 1100
		CITY:			BRIDGEPORT
		STATE:			CT
		ZIP:			06604
		BUSINESS PHONE:		2034165290

	MAIL ADDRESS:	
		STREET 1:		10 MIDDLE STREET
		STREET 2:		SUITE 1100
		CITY:			BRIDGEPORT
		STATE:			CT
		ZIP:			06604

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RockPort Capital Partners, L.P.
		CENTRAL INDEX KEY:			0001335900
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130992

	BUSINESS ADDRESS:	
		STREET 1:		160 FEDERAL STREET
		STREET 2:		18TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
		BUSINESS PHONE:		617-912-1445

	MAIL ADDRESS:	
		STREET 1:		160 FEDERAL STREET
		STREET 2:		18TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RP Co-Investment Fund I, L.P.
		CENTRAL INDEX KEY:			0001335901
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101131000

	BUSINESS ADDRESS:	
		STREET 1:		160 FEDERAL STREET
		STREET 2:		18TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
		BUSINESS PHONE:		617-912-1445

	MAIL ADDRESS:	
		STREET 1:		160 FEDERAL STREET
		STREET 2:		18TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RP Co-Investment Fund I GP, LLC
		CENTRAL INDEX KEY:			0001503232
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33710
		FILM NUMBER:		101130999

	BUSINESS ADDRESS:	
		STREET 1:		160 FEDERAL STREET
		STREET 2:		18TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
		BUSINESS PHONE:		617-912-1420

	MAIL ADDRESS:	
		STREET 1:		160 FEDERAL STREET
		STREET 2:		18TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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<ownershipDocument>

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    <documentType>4</documentType>

    <periodOfReport>2010-10-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000949428</issuerCik>
        <issuerName>CLEAN DIESEL TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>CDTI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001228600</rptOwnerCik>
            <rptOwnerName>ELLIS ALEXANDER III</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ROCKPORT CAPITAL PARTNERS, LP</rptOwnerStreet1>
            <rptOwnerStreet2>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001335900</rptOwnerCik>
            <rptOwnerName>RockPort Capital Partners, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
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            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001236155</rptOwnerCik>
            <rptOwnerName>ROCKPORT CAPITAL I LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001335901</rptOwnerCik>
            <rptOwnerName>RP Co-Investment Fund I, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001503232</rptOwnerCik>
            <rptOwnerName>RP Co-Investment Fund I GP, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001422108</rptOwnerCik>
            <rptOwnerName>James Janet Burrows</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001218568</rptOwnerCik>
            <rptOwnerName>JAMES WILLIAM E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001241877</rptOwnerCik>
            <rptOwnerName>MCDERMOTT CHARLES J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
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            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001418018</rptOwnerCik>
            <rptOwnerName>Prend David J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001422111</rptOwnerCik>
            <rptOwnerName>Wilson Stoddard Moran</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>160 FEDERAL STREET, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-10-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>375853</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>375853</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-10-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>26842</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>402695</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F3"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Warrants</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>7.92</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-10-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>40220</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2010-10-15</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>40220</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40220</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Warrants</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>7.92</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-10-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>15108</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2010-10-15</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>15108</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>55328</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F3"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">This filing is being made as the result of the acquisition of securities of Clean Diesel Technologies, Inc. (&quot;CDTI&quot;) by RockPort Capital Partners, L.P. and RP Co-Investment Fund I, L.P. in exchange for securities of Catalytic Solutions, Inc. (&quot;CSI&quot;) previously held thereby, pursuant to the merger (the &quot;Merger&quot;) of a wholly owned subsidiary of CDTI into CSI on October 15, 2010.  As a result of the Merger, CSI became a wholly owned subsidiary of CDTIl.  The reporting persons owned no securities of CDTI prior to the Merger.</footnote>
        <footnote id="F2">Such securities are held directly by RockPort Capital Partners, L.P., and may be deemed to be beneficially owned by RockPort Capital I, LLC, the general partner of RockPort Capital Partners, L.P, and by Alexander Ellis III, Janet B. James, William E. James, Charles J. McDermott, David J. Prend and Stoddard M. Wilson, who are the managing members of  RockPort Capital I, LLC.  All such persons other than RockPort Capital Partners, L.P. disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that such reporting person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.</footnote>
        <footnote id="F3">Such securities are held directly by RP Co-Investment Fund I, L.P. , and may be deemed to be beneficially owned by RP Co-Investment Fund I GP, LLC, the general partner of RP Co-Investment Fund I, L.P., and by Alexander Ellis III, Janet B. James, William E. James, Charles J. McDermott, David J. Prend and Stoddard M. Wilson, who are the managing members of  RP Co-Investment Fund I GP, LLC.  All such persons other than RP Co-Investment Fund I, L.P. disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that such reporting person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.</footnote>
        <footnote id="F4">The warrants expire on the earlier of (a) October 10, 2013 and (b) the date 30 days after CDTI notifies the warrant holder that the market price of CDTI's common stock has exceeded $10.30 for 10 consecutive days.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>ALEXANDER ELLIS III, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>ROCKPORT CAPITAL PARTNERS, LP, By: Rockport Capital I, LLC, General Partner, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>RP CO-INVESTMENT FUND I, L.P., By: RP Co-Investment Fund I GP, LLC, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>ROCKPORT CAPITAL I, LLC, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>RP CO-INVESTMENT FUND I GP, LLC, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>JANET B. JAMES, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>WILLIAM E. JAMES, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>CHARLES J. MCDERMOTT, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>DAVID J. PREND, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>STODDARD M. WILSON, By: /s/ Tom Scott, Attorney-in-Fact</signatureName>
        <signatureDate>2010-10-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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