UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. _2_)
Clean Diesel Technologies, Inc.
_____________________________________________
(Name of Issuer)
Common Shares, Par Value $0.01
_______________________________________________
(Title of Class of Securities)
18449C401
_________________________________________________
(CUSIP Number)
with a copy to:
Austin W. Marxe Allen B. Levithan, Esq.
527 Madison Avenue, Suite 2600 Lowenstein Sandler PC
New York, New York 10022 65 Livingston Avenue
Roseland, New Jersey 07068
(973) 597-2406
(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)
December 31, 2012
(Date of Event which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
____ Rule 13d-1(b)
_x__ Rule 13d-1(c)
____ Rule 13d-1(d)
*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter disclosures provided in a prior cover page.
The information required on the remainder of this cover page shall not be
deemed to be ?filed? for the purpose of Section 18 of the Securities
Exchange Act of 1934 (?Act?) or otherwise subject to the liabilities of
that
section of the Act but shall be subject to all other provisions of the
Act
(however, see the Notes).
Cusip No. 18449C401 13G Page 2 of 6 Pages
1.Names of Reporting Persons. I.R.S. Identification Nos. of above
persons
(entities only):
Austin W. Marxe and David M. Greenhouse
2. Check the Appropriate Box if a Member of a Group (See
Instructions):
(a) [ ] Not Applicable
(b) [ ]
3. SEC Use Only
4. Source of Funds (See Instructions): 00
5. Check if Disclosure of Legal Proceedings Is Required Pursuant
to
Items 2(d) or 2(e):
Not Applicable
6. Citizenship or Place of Organization: United States
Number of 7. Sole Voting Power: 0
Shares Beneficially 8. Shared Voting Power: 519,196*
Owned by
Each Reporting 9. Sole Dispositive Power: 0
Person With 10. Shared Dispositive Power: 519,196*__
11. Aggregate Amount Beneficially Owned by Each Reporting Person:
519,196*
12. Check if the Aggregate Amount in Row (11) Excludes Certain
Shares
(See Instructions): Not Applicable
13. Percent of Class Represented by Amount in Row (11): 7.2%*
14. Type of Reporting Person (See Instructions): IA, IN
* This is a joint filing by Austin W. Marxe (?Marxe?) and David M.
Greenhouse
(?Greenhouse?). Marxe and Greenhouse share sole voting and investment
power
over 85,566 Common Shares owned by Special Situations Cayman Fund, L.P.,
250,936 Common Shares owned by Special Situations Fund III QP, L.P.,
33,704
Common Shares owned by Special Situations Private Equity Fund, L.P.,
20,761
Common Shares owned by Special Situations Technology Fund, L.P., and
128,229
Common Shares owned by Special Situations Technology Fund II, L.P. See
Items
2 and 4 of this Schedule for additional information.
Page 3 of 6 Pages
Item 1. Security and Issuer:
(a) Clean Diesel Technologies, Inc.
(b) 4567 Telephone Road, Suite 206, Ventura, CA 93003
Item 2. (a) Name of Person Filing:
The persons filing this report are Austin W. Marxe (?Marxe?) and
David M. Greenhouse (?Greenhouse?), who are the controlling principals of
AWM
Investment Company, Inc. (?AWM?), the general partner of and investment
adviser to Special Situations Cayman Fund, L.P. (?Cayman?). AWM also
serves
as the general partner of MGP Advisers Limited Partnership (?MGP?), the
general partner of Special Situations Fund III QP, L.P. (?SSFQP?). Marxe
and
Greenhouse are members of MG Advisers L.L.C. (?MG?), the general partner
of
Special Situations Private Equity Fund, L.P. (?SSPE?). Marxe and
Greenhouse
are also members of SST Advisers, L.L.C. (?SSTA?), the general partner of
Special Situations Technology Fund, L.P. (?Tech?) and Special Situations
Technology Fund II, L.P. (?Tech II?). AWM serves as the investment
adviser to
SSFQP, SSPE, Tech and Tech 2. (SSFQP, Cayman, SSPE, Tech and Tech II will
hereafter be referred to as, the ?Funds?). The principal business of
each
Fund is to invest in equity and equity-related securities and other
securities of any kind or nature.
(b) Address of Principal Business Office or, if none,
Residence:
The principal business address for Marxe and Greenhouse is 527
Madison Avenue, Suite 2600, New York, NY 10022.
(c) Citizenship:
Austin W. Marxe and David M. Greenhouse are United
States citizens.
(d) Title of Class of Securities: Common Shares
(e) CUSIP Number: 18449C401.
Item 3. If this statement is filed pursuant to $240.13d-1(b) or
240.13d-
2(b), check whether
the person filing is a: Not Applicable
(a) ( ) Broker or Dealer registered under section 15 of the Act;
(b) ( ) Bank as defined in section 3(a) (6) of the Act;
(c) ( ) Insurance Company as defined in section 3(a) (19) of the Act;
(d) ( ) Investment Company registered under section 8 of the
Investment
Company Act of 1940;
(e) ( ) An Investment Adviser in accordance with $240.13d
-1(b)(I)(ii)(E);
(f) ( ) An employee benefit plan or endowment fund in accordance with
$240.13d-1(b)(I)(ii)(F);
Page 4 of 6 Pages
(g) ( ) A parent holding company or control person in accordance with
$240.13d-
1(b)(1)(ii)(G);
(h) ( ) A savings association as defined in Section 3(b) of the
Federal
Deposit Insurance
Act;
(i) ( ) A church plan that is excluded from the definition of an
investment company under section 3(c)(14) of the Investment
Company Act of 1940;
(j) ( ) Group, in accordance with $240.13d-1(b)(1)(ii)(J).
Item 4. Ownership:
(a) Amount Beneficially Owned: Messrs. Marxe and Greenhouse
beneficially own a total of 519,196 Common Shares. This amount includes
85,566 Common Shares owned by Cayman, 250,936 Common Shares owned by
SSFQP,
33,704 Common Shares owned by SSPE, 20,761 Common Shares owned by Tech
and
128,229 Common Shares owned by Tech II.
(b) Percent of Class: Messrs. Marxe and Greenhouse beneficially
own
7.2% of the outstanding shares, of which Cayman owns 1.2% of the
outstanding
shares, SSFQP owns 3.5% of the outstanding shares, SSPE owns 0.5% of the
outstanding shares, Tech owns 0.3% of the outstanding shares and Tech II
owns
1.8% of the outstanding shares.
(c) Number of Shares as to which the person has:
(i) Sole power to vote or to direct the vote: 0
(ii) Shared power to vote or to direct the vote: 519,196
(iii) Sole power to dispose or to direct the disposition of:
0
(iv) Shared power to dispose or to direct the disposition of:
519,196
Item 5. Ownership of Five Percent or Less of a Class: If this statement
is
being filed to report the fact that as of the date hereof the reporting
person has ceased to be the beneficial owner of more that five percent of
the
class of securities, check the following __.
Item 6.Ownership of More than Five Percent on Behalf of Another Person:
Not
Applicable.
Page 5 of 6 Pages
Item 7. Identification and Classification of the Subsidiary Which
Acquired
the Security being Reported on By the Parent Holding Company: Not
Applicable.
Item 8. Identification and Classification of Members of the Group: Not
applicable
Item 9. Notices of Dissolution of Group: Not applicable.
Item 10.Certification:
By signing below I certify that, to the best of my knowledge and
belief, the securities
referred to above were acquired and are held in the ordinary course of
business and were not
acquired and are not held for the purpose of or with the effect of
changing
or influencing the
control of the issuer of the securities and were not acquired and are not
held in connection with
or as a participant in any transaction having that purpose or effect.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and
belief, I
certify that the information set forth in this statement is true,
complete
and correct.
Dated: February 5, 2013
/s/ Austin W. Marxe
AUSTIN W. MARXE
/s/David M Greenhouse
DAVID M. GREENHOUSE
Attention: Intentional misstatements or omissions of fact constitute
Federal
criminal violations (See 18 U.S.C. 1001).
Page 6 of 6 Pages
JOINT FILING AGREEMENT
Austin W. Marxe and David M. Greenhouse hereby agree that the
Schedule
13G to which this agreement is attached is filed on behalf of each of
them.
/s/_Austin W. Marxe
Austin W. Marxe
/s/_David M. Greenhouse
David M. Greenhouse
-6-
S5313/1
1319328.02