Exhibit 99.1

NEITHER THESE SECURITIES NOR THE SECURITIES ISSUABLE UPON EXERCISE OF THESE SECURITIES HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS AS EVIDENCED BY A LEGAL OPINION OF COUNSEL TO THE TRANSFEROR TO SUCH EFFECT, THE SUBSTANCE OF WHICH SHALL BE REASONABLY ACCEPTABLE TO THE COMPANY. THESE SECURITIES AND THE SECURITIES ISSUABLE UPON EXERCISE OF THESE SECURITIES MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT SECURED BY SUCH SECURITIES.

CLEAN DIESEL TECHNOLOGIES, INC.

UNDERWRITER WARRANT

Clean Diesel Technologies, Inc., a Delaware corporation (the “Company”), hereby certifies that, as partial compensation for services, Roth Capital Partners LLC or its registered assigns (the “Holder”), is entitled to purchase from the Company up to a total of [ — ] ([ — ]) shares of Common Stock (each such share, a “Warrant Share” and all such shares, the “Warrant Shares”), at any time and from time to time beginning on December 25, 2013 and through and including June 28, 2018 (the “Expiration Date”), and subject to the following terms and conditions:

1. Definitions . As used in this Warrant, the following terms shall have the respective definitions set forth in this Section 1.

“ Affiliate ” means any Person that, directly or indirectly through one or more intermediaries, controls or is controlled by or is under common control with a Person, as such terms are used in and construed under Rule 144.

“ Business Day ” means any day except Saturday, Sunday and any day which is a federal legal holiday or a day on which banking institutions in the State of New York are authorized or required by law or other governmental action to close.

“ Common Stock ” means the common stock of the Company, $0.01 par value per share, and any securities into which such common stock may hereafter be reclassified or for which it may be exchanged as a class.

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended.

“ Exercise Price ” means $1.25, subject to adjustment in accordance with Section 9.

“ Fundamental Transaction ” means any of the following: (1) the Company effects any merger or consolidation of the Company with or into another Person, (2) the Company effects any sale of all or substantially all of its assets in one or a series of related transactions, provided however, that the sale by the Company of any manufacturing business segment, product line or division shall not be deemed to be a sale of substantially all of its assets, (3) any tender offer or exchange offer (whether by the Company or another Person) is completed pursuant to which holders of Common Stock are permitted to tender or exchange their shares for other securities, cash or property, or (4) the Company effects any reclassification of the Common Stock or any compulsory share exchange pursuant to which the Common Stock is effectively converted into or exchanged for other securities, cash or property.

“ New York Courts ” means the state and federal courts sitting in the City of New York, Borough of Manhattan.

“ Original Issue Date ” means the Original Issue Date first set forth on the first page of this Warrant.

“ Person ” means an individual or corporation, partnership, trust, incorporated or unincorporated association, joint venture, limited liability company, joint stock company, government (or an agency or subdivision thereof) or other entity of any kind.

“ Rule 144 ” means Rule 144 promulgated by the SEC pursuant to the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the SEC on having substantially the same effect as such Rule.

“ SEC ” means the Securities and Exchange Commission.

“ Securities Act ” means the Securities Act of 1933, as amended.

“ Subsidiary ” means any “significant subsidiary” as defined in Rule 1-02(w) of Regulation S-X promulgated by the SEC under the Exchange Act.

“ Trading Day ” means (i) a day on which the Common Stock is traded or quoted on a Trading Market, or (ii) if the Common Stock is not traded or quoted on any Trading Market, a day on which the Common Stock is quoted in the over-the-counter market as reported by the Pink Sheets LLC (or any similar organization or agency succeeding to its functions of reporting prices); provided, that in the event that the Common Stock is not traded or quoted as set forth in (i) or (ii) hereof, then Trading Day shall mean a Business Day.

“ Trading Market ” means whichever of the New York Stock Exchange, NYSE Amex Equities, the NASDAQ Global Select Market, the NASDAQ Global Market, the NASDAQ Capital Market or OTC Bulletin Board on which the Common Stock is listed or quoted for trading on the date in question.

“ Warrant Shares ” means the shares of Common Stock issuable upon exercise of this Warrant.

2. Registration of Warrant . The Company shall register this Warrant upon records to be maintained by the Company for that purpose (the “Warrant Register”), in the name of the record Holder hereof from time to time. The Company may deem and treat the registered Holder of this Warrant as the absolute owner hereof for the purpose of any exercise hereof or any distribution to the Holder, and for all other purposes, absent actual notice to the contrary.

3. Registration of Transfers . Subject to the limitation set forth in the last sentence of Section 4 hereof, the Company shall register the transfer of any portion of this Warrant in the Warrant Register, upon surrender of this Warrant, with the Form of Assignment attached hereto duly completed and signed, to the Company at its address specified herein. Upon any such registration or transfer, a new Warrant to purchase Common Stock, in substantially the form of this Warrant (any such new Warrant, a “New Warrant”), evidencing the portion of this Warrant so transferred shall be issued to the transferee and a New Warrant evidencing the remaining portion of this Warrant not so transferred, if any, shall be issued to the transferring Holder. The acceptance of the New Warrant by the transferee thereof shall be deemed the acceptance by such transferee of all of the rights and obligations of a holder of a Warrant.

4. Exercise and Duration of Warrants . This Warrant shall be exercisable by the registered Holder at any time and from time to time from and after December 28, 2013 ) through and including the Expiration Date. At 6:30 p.m., New York City time on the Expiration Date which in accordance with FINRA Rule 5110(f)(2)(H) shall not be more than five (5) years from June 28, 2013, the portion of this Warrant not exercised prior thereto shall be and become void and of no value. The Company may not call or redeem any portion of this Warrant without the prior written consent of the affected Holder. This Warrant shall not be sold, transferred, assigned, pledged, or hypothecated, or be the subject of any hedging, short sale, derivative, put, or call transaction that would result in the effective economic disposition of this Warrant by any person for a period of 180 days immediately following June 28, 2013, except as provided in FINRA Rule 5110(g)(2).

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5. Delivery of Warrant Shares .

(a) To effect exercises hereunder, the Holder shall not be required to physically surrender this Warrant unless the aggregate Warrant Shares represented by this Warrant is being exercised. Upon delivery of the Exercise Notice (in the form attached hereto) to the Company (with the attached Warrant Shares Exercise Log) at its address for notice set forth herein and upon payment of the Exercise Price multiplied by the number of Warrant Shares that the Holder intends to purchase hereunder (provided, that, in lieu of the payment of the Exercise Price, the Holder may have notified the Company in its Exercise Notice that such exercise was made pursuant to a Cashless Exercise (as defined in Section 11 hereof)), the Company shall promptly (but in no event later than five Trading Days) after the Date of Exercise (as defined herein)) issue and deliver to the Holder, a certificate for the Warrant Shares issuable upon such exercise. The Company shall, upon request of the Holder and subsequent to the date on which a registration statement covering the resale of the Warrant Shares, if any, has been declared effective by the SEC, use its reasonable best efforts to deliver Warrant Shares hereunder electronically through the Depository Trust Corporation or another established clearing corporation performing similar functions, if available, provided, that, the Company may, but will not be required to change its transfer agent if its current transfer agent cannot deliver Warrant Shares electronically through the Depository Trust Corporation. A “Date of Exercise” means the date on which the Holder shall have delivered to the Company: (i) the Exercise Notice (with the Warrant Exercise Log attached to it), appropriately completed and duly signed and (ii) payment of the Exercise Price for the number of Warrant Shares so indicated by the Holder to be purchased.

(b) If by the fifth Trading Day after a Date of Exercise the Company fails to deliver the required number of Warrant Shares in the manner required pursuant to Section 5(a), then the Holder will have the right to rescind such exercise.

(c) The Company’s obligations to issue and deliver Warrant Shares in accordance with the terms hereof are absolute and unconditional, irrespective of any action or inaction by the Holder to enforce the same, any waiver or consent with respect to any provision hereof, the recovery of any judgment against any Person or any action to enforce the same, or any setoff, counterclaim, recoupment, limitation or termination, or any breach or alleged breach by the Holder or any other Person of any obligation to the Company or any violation or alleged violation of law by the Holder or any other Person, and irrespective of any other circumstance which might otherwise limit such obligation of the Company to the Holder in connection with the issuance of Warrant Shares. Nothing herein shall limit a Holder’s right to pursue any other remedies available to it hereunder, at law or in equity including, without limitation, a decree of specific performance and/or injunctive relief with respect to the Company’s failure to timely deliver certificates representing Warrant Shares upon exercise of the Warrant as required pursuant to the terms hereof.

6. Charges , Taxes and Expenses. Issuance and delivery of Warrant Shares upon exercise of this Warrant shall be made without charge to the Holder for any issue or transfer tax, withholding tax, transfer agent fee or other incidental tax or expense in respect of the issuance of such certificates, all of which taxes and expenses shall be paid by the Company; provided, however, that the Company shall not be required to pay any tax which may be payable in respect of any transfer involved in the registration of any certificates for Warrant Shares or Warrants in a name other than that of the Holder. The Holder shall be responsible for all other tax liability that may arise as a result of holding or transferring this Warrant or receiving Warrant Shares upon exercise hereof.

7. Replacement of Warrant . If this Warrant is mutilated, lost, stolen or destroyed, the Company shall issue or cause to be issued in exchange and substitution for and upon cancellation hereof, or in lieu of and substitution for this Warrant, a New Warrant, but only upon receipt of evidence reasonably satisfactory to the Company of such loss, theft or destruction and customary and reasonable indemnity (which shall not include a surety bond), if requested. Applicants for a New Warrant under such circumstances shall also comply with such other reasonable regulations and procedures and pay such other reasonable third-party costs as the Company may prescribe. If a New Warrant is requested as a result of a mutilation of this Warrant, then the Holder shall deliver such mutilated Warrant to the Company as a condition precedent to the Company’s obligation to issue the New Warrant.

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8. Reservation of Warrant Shares . The Company covenants that it will at all times reserve and keep available out of the aggregate of its authorized but unissued and otherwise unreserved Common Stock, solely for the purpose of enabling it to issue Warrant Shares upon exercise of this Warrant as herein provided, the number of Warrant Shares which are then issuable and deliverable upon the exercise of this entire Warrant, free from preemptive rights or any other contingent purchase rights of Persons other than the Holder (taking into account the adjustments and restrictions of Section 9). The Company covenants that all Warrant Shares so issuable and deliverable shall, upon issuance and the payment of the applicable Exercise Price in accordance with the terms hereof, be duly and validly authorized, issued and fully paid and nonassessable.

9. Certain Adjustments . The Exercise Price and number of Warrant Shares issuable upon exercise of this Warrant are subject to adjustment from time to time as set forth in this Section 9.

(a) Stock Dividends and Splits . If the Company, at any time while this Warrant is outstanding, (i) pays a stock dividend on its Common Stock or otherwise makes a distribution on any class of capital stock that is payable in shares of Common Stock, (ii) subdivides outstanding shares of Common Stock into a larger number of shares, or (iii) combines outstanding shares of Common Stock into a smaller number of shares, then in each such case the Exercise Price shall be multiplied by a fraction of which the numerator shall be the number of shares of Common Stock outstanding immediately before such event and of which the denominator shall be the number of shares of Common Stock outstanding immediately after such event. Any adjustment made pursuant to clause (i) of this paragraph shall become effective immediately after the record date for the determination of stockholders entitled to receive such dividend or distribution, and any adjustment pursuant to clause (ii) or (iii) of this paragraph shall become effective immediately after the effective date of such subdivision or combination.

(b) Fundamental Transactions . If, at any time while this Warrant is outstanding there is a Fundamental Transaction, then the Holder shall have the right thereafter to receive, upon exercise of this Warrant, the same amount and kind of securities, cash or property as it would have been entitled to receive upon the occurrence of such Fundamental Transaction if it had been, immediately prior to such Fundamental Transaction, the holder of the number of Warrant Shares then issuable upon exercise in full of this Warrant (the “Alternate Consideration”). For purposes of any such exercise, the determination of the Exercise Price shall be appropriately adjusted to apply to such Alternate Consideration based on the amount of Alternate Consideration issuable in respect of one share of Common Stock in such Fundamental Transaction, and the Company shall apportion the Exercise Price among the Alternate Consideration in a reasonable manner reflecting the relative value of any different components of the Alternate Consideration. If holders of Common Stock are given any choice as to the securities, cash or property to be received in a Fundamental Transaction, then the Holder shall be given the same choice as to the Alternate Consideration it receives upon any exercise of this Warrant following such Fundamental Transaction. At the Holder’s option and request, any successor to the Company or surviving entity in such Fundamental Transaction shall issue to the Holder a new warrant substantially in the form of this Warrant and consistent with the foregoing provisions and evidencing the Holder’s right to purchase the Alternate Consideration for the aggregate Exercise Price upon exercise thereof. The terms of any agreement pursuant to which a Fundamental Transaction is effected shall include terms requiring any such successor or surviving entity to comply with the provisions of this paragraph (b) and insuring that the Warrant (or any such replacement security) will be similarly adjusted upon any subsequent transaction analogous to a Fundamental Transaction.

(c) Number of Warrant Shares . Simultaneously with any adjustment to the Exercise Price pursuant to this Section 9, the number of Warrant Shares that may be purchased upon exercise of this Warrant shall be increased or decreased proportionately, so that after such adjustment the aggregate Exercise Price payable hereunder for the adjusted number of Warrant Shares shall be the same as the aggregate Exercise Price in effect immediately prior to such adjustment.

(d) Calculations . All calculations under this Section 9 shall be made to the nearest cent or the nearest 1/100th of a share, as applicable. The number of shares of Common Stock outstanding at any given time shall not include shares owned or held by or for the account of the Company, and the disposition of any such shares shall be considered an issue or sale of Common Stock.

(e) Notice of Adjustments . Upon the occurrence of each adjustment pursuant to this Section 9, the Company at its expense will promptly compute such adjustment in accordance with the terms of this Warrant

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and prepare a certificate setting forth such adjustment, including a statement of the adjusted Exercise Price and adjusted number or type of Warrant Shares or other securities issuable upon exercise of this Warrant (as applicable), describing the transactions giving rise to such adjustments and showing in detail the facts upon which such adjustment is based. Upon written request, the Company will promptly deliver a copy of each such certificate to the Holder and to the Company’s Transfer Agent.

(f) Notice of Corporate Events . If the Company (i) declares a dividend or any other distribution of cash, securities or other property in respect of its Common Stock, including without limitation any granting of rights or warrants to subscribe for or purchase any capital stock of the Company or any Subsidiary, (ii) authorizes or approves, enters into any agreement contemplating or solicits stockholder approval for any Fundamental Transaction or (iii) authorizes the voluntary dissolution, liquidation or winding up of the affairs of the Company, then the Company shall deliver to the Holder a notice describing the material terms and conditions of such transaction (but only to the extent such disclosure would not result in the dissemination of material, non-public information to the Holder) at least 10 calendar days prior to the applicable record or effective date on which a Person would need to hold Common Stock in order to participate in or vote with respect to such transaction, and the Company will take all steps reasonably necessary in order to give the Holder the practical opportunity to exercise this Warrant prior to such time so as to participate in or vote with respect to such transaction; provided, however, that the failure to deliver such notice or any defect therein shall not affect the validity of the corporate action required to be described in such notice.

10. Payment of Exercise Price . The Holder shall pay the Exercise Price by delivering immediately available funds if the Holder did not notify the Company in the Exercise Notice that the exercise was made pursuant to a Cashless Exercise as further described in Section 11 hereof.

11. Cashless Exercise . Notwithstanding anything contained herein to the contrary (other than Section 12 below), the Holder may, in lieu of making the cash payment otherwise contemplated to be made to the Company upon exercise, elect instead to receive upon such exercise the “Net Number” of shares of Common Stock determined according to the following formula (a “Cashless Exercise”):

For purposes of the foregoing formula:

A = the total number of shares with respect to which this Warrant is then being exercised.

B = as applicable: (i) the closing sale price of the Common Stock on the Trading Day immediately preceding the date of the applicable Exercise Notice if such Exercise Notice is (1) both executed and delivered pursuant to Section 5 hereof on a day that is not a Trading Day or (2) both executed and delivered pursuant to Section 5 hereof on a Trading Day prior to the opening of “regular trading hours” (as defined in Rule 600(b)(64) of Regulation NMS promulgated under the federal securities laws) on such Trading Day, (ii) the bid price of the Common Stock as of the time of the Holder’s execution of the applicable Exercise Notice if such Exercise Notice is executed during “regular trading hours” on a Trading Day pursuant to Section 5 hereof, (iii) the closing sale price of the Common Stock on the date of the applicable Exercise Notice if the date of such Exercise Notice is a Trading Day and such Exercise Notice is both executed and delivered pursuant to Section 5 hereof after the close of “regular trading hours” on such Trading Day, or (iv) if the Common Stock is not traded in such manner that the quotations referred to above are available, the fair value per share of the Common Stock as determined by the Board of Directors of the Company in good faith.

C = the Exercise Price then in effect for the applicable Warrant Shares at the time of such exercise.

12. Limitations on Exercise. Notwithstanding anything to the contrary contained herein, the number of Warrant Shares that may be acquired by the Holder upon any exercise of this Warrant (or otherwise in respect hereof) shall be limited to the extent necessary to insure that, following such exercise (or other issuance), the total

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number of shares of Common Stock then beneficially owned by such Holder and its Affiliates and any other Persons whose beneficial ownership of Common Stock would be aggregated with the Holder’s for purposes of Section 13(d) of the Exchange Act, does not exceed 9.99% of the total number of issued and outstanding shares of Common Stock (including for such purpose the shares of Common Stock issuable upon such exercise). For such purposes, beneficial ownership shall be determined in accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder. This provision shall not restrict the number of shares of Common Stock which a Holder may receive or beneficially own in order to determine the amount of securities or other consideration that such Holder may receive in the event of a Fundamental Transaction as contemplated in Section 9 of this Warrant. This restriction may not be waived. Notwithstanding anything to the contrary contained in this Warrant, (a) no term of this Section may be waived by any party, nor amended such that the threshold percentage of ownership would be directly or indirectly increased, (b) this restriction runs with the Warrant and may not be modified or waived by any subsequent holder hereof and (c) any attempted waiver, modification or amendment of this Section will be void ab initio.

13. No Fractional Shares . No fractional shares of Common Stock will be issued in connection with any exercise of this Warrant. In lieu of any fractional shares which would, otherwise be issuable, the Company shall pay cash equal to the product of such fraction multiplied by the closing price of one Warrant Share as reported by the applicable Trading Market on the date of exercise.

14. Notices . Any and all notices or other communications or deliveries hereunder (including, without limitation, any Exercise Notice) shall be in writing and shall be deemed given and effective on the earliest of (i) the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number specified in this Section prior to 6:30 p.m. (New York City time) on a Trading Day, (ii) the next Trading Day after the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number specified in this Section on a day that is not a Trading Day or later than 6:30 p.m. (New York City time) on any Trading Day, (iii) the Trading Day following the date of mailing, if sent by nationally recognized overnight courier service, or (iv) upon actual receipt by the party to whom such notice is required to be given. The addresses for such communications shall be: (i) if to the Company, to 4567 Telephone Road, Suite 206, Ventura, CA 93033, Attn: Chief Financial Officer, or to Facsimile No.: (805) 639-9466 (or such other address as the Company shall indicate in writing in accordance with this Section), or (ii) if to the Holder, to the address or facsimile number appearing on the Warrant Register or such other address or facsimile number as the Holder may provide to the Company in accordance with this Section.

15. Warrant Agent . The Company shall serve as warrant agent under this Warrant. Upon 10 days’ notice to the Holder, the Company may appoint a new warrant agent. Any corporation into which the Company or any new warrant agent may be merged or any corporation resulting from any consolidation to which the Company or any new warrant agent shall be a party or any corporation to which the Company or any new warrant agent transfers substantially all of its corporate trust or shareholders services business shall be a successor warrant agent under this Warrant without any further act. Any such successor warrant agent shall promptly cause notice of its succession as warrant agent to be mailed (by first class mail, postage prepaid) to the Holder at the Holder’s last address as shown on the Warrant Register.

16. Miscellaneous .

(a) This Warrant shall be binding on and inure to the benefit of the parties hereto and their respective successors and assigns. Subject to the preceding sentence, nothing in this Warrant shall be construed to give to any Person other than the Company and the Holder any legal or equitable right, remedy or cause of action under this Warrant. This Warrant may be amended only in writing signed by the Company and the Holder and their successors and assigns.

(b) All questions concerning the construction, validity, enforcement and interpretation of this Warrant shall be governed by and construed and enforced in accordance with the internal laws of the State of New York, without regard to the principles of conflicts of law thereof. Each party agrees that all legal proceedings concerning the interpretations, enforcement and defense of this Warrant and the transactions herein contemplated (“Proceedings”) (whether brought against a party hereto or its respective Affiliates, employees or agents) shall be commenced exclusively in the New York Courts. Each party hereto hereby irrevocably submits to the exclusive

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jurisdiction of the New York Courts for the adjudication of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein, and hereby irrevocably waives, and agrees not to assert in any Proceeding, any claim that it is not personally subject to the jurisdiction of any New York Court, or that such Proceeding has been commenced in an improper or inconvenient forum. Each party hereto hereby irrevocably waives personal service of process and consents to process being served in any such Proceeding by mailing a copy thereof via registered or certified mail or overnight delivery (with evidence of delivery) to such party at the address in effect for notices to it under this Warrant and agrees that such service shall constitute good and sufficient service of process and notice thereof. Nothing contained herein shall be deemed to limit in any way any right to serve process in any manner permitted by law. Each party hereto hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Warrant or the transactions contemplated hereby. If either party shall commence a Proceeding to enforce any provisions of this Warrant, then the prevailing party in such Proceeding shall be reimbursed by the other party for its attorney’s fees and other costs and expenses incurred with the investigation, preparation and prosecution of such Proceeding.

(c) The headings herein are for convenience only, do not constitute a part of this Warrant and shall not be deemed to limit or affect any of the provisions hereof.

(d) In case any one or more of the provisions of this Warrant shall be invalid or unenforceable in any respect, the validity and enforceability of the remaining terms and provisions of this Warrant shall not in any way be affected or impaired thereby and the parties will attempt in good faith to agree upon a valid and enforceable provision which shall be a commercially reasonable substitute therefor, and upon so agreeing, shall incorporate such substitute provision in this Warrant.

(e) Prior to exercise of this Warrant, the Holder hereof shall not, by reason of being a Holder, be entitled to any rights of a stockholder with respect to the Warrant Shares.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK,

SIGNATURE PAGE FOLLOWS]

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IN WITNESS WHEREOF, the Company has caused this Warrant to be duly executed by its authorized officer as of the date first indicated above.

[Signature Page to Warrant]

EXERCISE NOTICE

CLEAN DIESEL TECHNOLOGIES, INC.

WARRANT DATED                     

The undersigned Holder hereby irrevocably elects to purchase                  shares of Common Stock pursuant to the above referenced Warrant. Capitalized terms used herein and not otherwise defined have the respective meanings set forth in the Warrant.

             a “Cash Exercise” with respect to                  Warrant Shares; and/or

             a “Cashless Exercise” with respect to                  Warrant Shares.

Warrant Shares Exercise Log

CLEAN DIESEL TECHNOLOGIES, INC.

WARRANT DATED                     

WARRANT NO. [            ]

FORM OF ASSIGNMENT

[To be completed and signed only upon transfer of Warrant]

FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers unto              the right represented by the above-captioned Warrant to purchase                  shares of Common Stock to which such Warrant relates and appoints              attorney to transfer said right on the books of the Company with full power of substitution in the premises.

Exhibit 99.2

THIS WARRANT HAS NOT BEEN AND WILL NOT REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS. THE HOLDER HEREOF, BY PURCHASING THIS WARRANT, AGREES FOR THE BENEFIT OF THE COMPANY THAT THIS WARRANT MAY NOT BE OFFERED, SOLD, PLEDGED, OR OTHERWISE TRANSFERRED BY SUCH HOLDER PRIOR TO THE LATER OF THE (X) SIX MONTHS FOLLOWING THE ISSUANCE HEREOF OR (Y) IF APPLICABLE, THREE MONTHS AFTER IT CEASES TO BE AN AFFILIATE, OTHER THAN (1) TO THE COMPANY, (2) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE U.S. SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND IN ACCORDANCE WITH ANY APPLICABLE LAWS OF ANY STATE OF THE UNITED STATES, (3) IN AN OFFSHORE TRANSACTION COMPLYING WITH REGULATION S UNDER THE SECURITIES ACT, (4) PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT PROVIDED BY RULE 144, IF APPLICABLE, UNDER THE SECURITIES ACT OR (5) IN A TRANSACTION THAT DOES NOT REQUIRE REGISTRATION UNDER THE SECURITIES ACT BUT IS IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS AND IN RELATION TO WHICH THE HOLDER HAS FURNISHED TO THE COMPANY AN OPINION TO SUCH EFFECT FROM COUNSEL OF RECOGNISED STANDING IN FORM AND SUBSTANCE SATISFACTORY TO THE COMPANY PRIOR TO SUCH OFFER, SALE, PLEDGE OR TRANSFER. THE HOLDER HEREOF, BY ACCEPTANCE OF THIS WARRANT, REPRESENTS AND AGREES FOR THE BENEFIT OF THE COMPANY THAT IT IS A NON-U.S. PERSON, AND ACKNOWLEDGES THAT HEDGING TRANSACTIONS INVOLVING THIS WARRANT MAY NOT BE CONDUCTED UNLESS CONDUCTED IN COMPLIANCE WITH THE SECURITIES ACT. THIS WARRANT IS NOT IMMEDIATELY EXERCISABLE IN FULL.

COMMON STOCK PURCHASE WARRANT

CLEAN DIESEL TECHNOLOGIES, INC.

THIS COMMON STOCK PURCHASE WARRANT (the “ Warrant ”) certifies that, for value received, Kanis S.A. (the “ Holder ”) is entitled, upon the terms and subject to the limitations on exercise and the conditions hereinafter set forth, at any time on or after the Issue Date and on or prior to the close of business on the five-year anniversary of the Issue Date (the “ Termination Date ”) but not thereafter, to subscribe for and purchase from Clean Diesel Technologies Inc., a Delaware corporation (the “ Company ”), up to 94,000 shares (the “ Warrant Shares ”) of common stock, par value $0.01 per share (“Common Stock”). The purchase price of one share of Common Stock under this Warrant shall be equal to the Exercise Price, as defined in Section 2(b).

Section 1 . Definitions . Capitalized terms used herein shall have the meanings given to them herein. As used herein, “Business Day” means any day on which the New York Stock Exchange, Inc. is open for trading

Section 2 . Exercise .

a) Exercise of Warrant . Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, from time to time on or before the Termination Date, subject to the terms and conditions herein, by delivery to the Company (or such other office or agency of the Company as it may designate by notice in writing to the registered Holder at the address of the Holder appearing on the books of the Company) of a duly executed facsimile copy of the Notice of Exercise Form annexed hereto with payment to the company of the exercise price of the Warrant Shares stated in the notice to be purchased. The Holder and any assignee, by acceptance of this Warrant, acknowledge and agree that, by reason of the provisions of this paragraph, following the purchase of a portion of the Warrant Shares hereunder, the number of Warrant Shares available for purchase hereunder at any given time may be less than the amount stated on the face hereof.

b) Exercise Price . The exercise price per share of the Common Stock under this Warrant shall be $1.25 , subject to adjustment hereunder (the “ Exercise Price ”).

c) Mechanics of Exercise .

i. Delivery of Certificates Upon Exercise . Certificates for shares purchased hereunder shall be transmitted by the transfer agent for the Common Stock (the “Transfer Agent”) to the Holder by physical delivery to the address specified by the Holder in the Notice of Exercise or, if available, by crediting the account of the Holder’s prime broker with the Depository Trust Company through its Deposit Withdrawal Agent Commission (“ DWAC ”) system.

ii. Delivery of New Warrants Upon Exercise . If this Warrant shall have been exercised in part, the Company shall, at the request of the Holder and upon surrender of this Warrant certificate, at the time of delivery of the certificate or certificates representing Warrant Shares, deliver to Holder a new Warrant evidencing the rights of Holder to purchase the unpurchased Warrant Shares called for by this Warrant, which new Warrant shall in all other respects be identical with this Warrant.

iii. No Fractional Shares or Scrip . No fractional shares or scrip representing fractional shares shall be issued upon the exercise of this Warrant. As to any fraction of a share which the Holder would otherwise be entitled to purchase upon such exercise, the Company shall, at its election, either pay a cash adjustment in respect of such final fraction in an amount equal to such fraction multiplied by the Exercise Price or round up to the next whole share.

iv. Charges, Taxes and Expenses . Issuance of certificates for Warrant Shares shall be made without charge to the Holder for any issue or transfer tax or

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other incidental expense in respect of the issuance of such certificate, all of which taxes and expenses shall be paid by the Company, and such certificates shall be issued in the name of the Holder or in such name or names as may be directed by the Holder; provided , however , that in the event certificates for Warrant Shares are to be issued in a name other than the name of the Holder, this Warrant when surrendered for exercise shall be accompanied by the Assignment Form attached hereto duly executed by the Holder and the Company may require, as a condition thereto, the payment of a sum sufficient to reimburse it for any transfer tax incidental thereto.

v. Closing of Books . The Company will not close its stockholder books or records in any manner which prevents the timely exercise of this Warrant, pursuant to the terms hereof.

Section 3 . Certain Adjustments .

a) Stock Dividends and Splits . If the Company, at any time while this Warrant is outstanding: (i) pays a stock dividend or otherwise makes a distribution or distributions on shares of its Common Stock or any other equity or equity equivalent securities payable in shares of Common Stock (which, for avoidance of doubt, shall not include any shares of Common Stock issued by the Company upon exercise of this Warrant), (ii) subdivides outstanding shares of Common Stock into a larger number of shares, (iii) combines (including by way of reverse stock split) outstanding shares of Common Stock into a smaller number of shares, or (iv) issues by reclassification of shares of the Common Stock any shares of capital stock of the Company, then in each case the Exercise Price shall be multiplied by a fraction of which the numerator shall be the number of shares of Common Stock (excluding treasury shares, if any) outstanding immediately before such event and of which the denominator shall be the number of shares of Common Stock outstanding immediately after such event. Any adjustment made pursuant to this Section 3(a) shall become effective immediately after the record date for the determination of stockholders entitled to receive such dividend or distribution and shall become effective immediately after the effective date in the case of a subdivision, combination or re-classification.

b) Pro Rata Distributions . If the Company, at any time while this Warrant is outstanding, shall distribute to all holders of Common Stock (and not to the Holder) evidences of its indebtedness or assets (including cash and cash dividends) or rights or warrants to subscribe for or purchase any security other than the Common Stock (which shall be subject to Section 3(b)), then in each such case the Exercise Price shall be adjusted by multiplying the Exercise Price in effect immediately prior to the record date fixed for determination of stockholders entitled to receive such distribution by a fraction of which the denominator shall be the VWAP (as defined below) determined as of the record date mentioned above, and of which the numerator shall be such VWAP (as defined below) on such record date less the then per share fair market value at such record date of the portion of such assets or evidence of indebtedness so distributed applicable to one outstanding share of the Common Stock as determined by the Board of Directors in good faith. In either case the adjustments shall be described in a statement

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provided to the Holder of the portion of assets or evidences of indebtedness so distributed or such subscription rights applicable to one share of Common Stock. Such adjustment shall be made whenever any such distribution is made and shall become effective immediately after the record date mentioned above.

“ VWAP ” means, for any date, the price determined by the first of the following clauses that applies: (a) if the Common Stock is then listed or quoted on whichever of the New York Stock Exchange, NYSE Amex Equities, the NASDAQ Global Select Market, the NASDAQ Global Market or the NASDAQ Capital Market on which the Common Stock is listed or quoted for trading on the date in question (a “ Trading Market”), the daily volume weighted average price of the Common Stock for such date (or the nearest preceding date) on the Trading Market on which the Common Stock is then listed or quoted as reported by Bloomberg L.P. (based on a Trading Day from 9:30 a.m. (New York City time) to 4:02 p.m. (New York City time), (b) if the OTC Bulletin Board is not a Trading Market, the volume weighted average price of the Common Stock for such date (or the nearest preceding date) on the OTC Bulletin Board, (c) if the Common Stock is not then listed or quoted for trading on the OTC Bulletin Board and if prices for the Common Stock are then reported in the “Pink Sheets” published by Pink OTC Markets, Inc. (or a similar organization or agency succeeding to its functions of reporting prices), the most recent bid price per share of the Common Stock so reported, or (d) in all other cases, the fair market value of a share of Common Stock as determined by an independent appraiser selected in good faith by the Holders of a majority in interest of the Securities then outstanding and reasonably acceptable to the Company, the fees and expenses of which shall be paid by the Company.

c) Fundamental Transaction . If, at any time while this Warrant is outstanding, (i) the Company, directly or indirectly, in one or more related transactions effects any merger or consolidation of the Company with or into another Person in which the Company is not the surviving entity or the stockholders of the Company immediately prior to such merger or consolidation do not own, directly or indirectly, at least 50% of the outstanding voting securities of the surviving entity, (ii) the Company, directly or indirectly, effects any sale, lease, license, assignment, transfer, conveyance or other disposition of all or substantially all of its assets in one or a series of related transactions; provided, however, that a sale by the Company of any manufacturing business segment, product line or division shall not be deemed to be a sale of substantially all of the assets of the Company, (iii) any, direct or indirect, purchase offer, tender offer or exchange offer (whether by the Company or another Person) is completed pursuant to which all or substantially all of the holders of Common Stock are permitted to sell, tender or exchange their shares for other securities, cash or property and has been accepted by the holders of 50% or more of the outstanding Common Stock, or (iv) the Company, directly or indirectly, in one or more related transactions effects any reclassification, reorganization or recapitalization of the Common Stock or any compulsory share exchange pursuant to which the Common Stock is effectively converted into or exchanged for other securities, cash or property (other than as a result of a subdivision or combination of shares of Common Stock covered by Section 3(a) above), (each a “ Fundamental Transaction ”),

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then, upon any subsequent exercise of this Warrant, the Holder shall have the right to receive, for each Warrant Share that would have been issuable upon such exercise immediately prior to the occurrence of such Fundamental Transaction, at the option of the Holder (without regard to any limitation in Section 2(e) on the exercise of this Warrant), the number of shares of Common Stock of the successor or acquiring corporation or of the Company, if it is the surviving corporation, and any additional consideration (the “ Alternate Consideration ”) receivable as a result of such Fundamental Transaction by a holder of the number of shares of Common Stock for which this Warrant is exercisable immediately prior to such Fundamental Transaction (without regard to any limitation in Section 2(e) on the exercise of this Warrant). For purposes of any such exercise, the determination of the Exercise Price shall be appropriately adjusted to apply to such Alternate Consideration based on the amount of Alternate Consideration issuable in respect of one share of Common Stock in such Fundamental Transaction, and the Company shall apportion the Exercise Price among the Alternate Consideration in a reasonable manner reflecting the relative value of any different components of the Alternate Consideration. If holders of Common Stock are given any choice as to the securities, cash or property to be received in a Fundamental Transaction, then the Holder shall be given the same choice as to the Alternate Consideration it receives upon any exercise of this Warrant following such Fundamental Transaction. Notwithstanding anything to the contrary, in the event of a Fundamental Transaction other than one in which a Successor Entity (as defined below) that is a publicly traded corporation whose stock is quoted or listed for trading on an Eligible Market assumes this Warrant such that the Warrant shall be exercisable for the publicly traded Common Stock of such Successor Entity, the Company or any Successor Entity shall, at the Holder’s option, exercisable at any time concurrently with, or within 30 days after, the consummation of the Fundamental Transaction, purchase this Warrant from the Holder by paying to the Holder an amount of cash equal to the Black Scholes Value of the remaining unexercised portion of this Warrant on the date of the consummation of such Fundamental Transaction. As used herein (w) “ Black Scholes Value ” means the value of this Warrant based on the Black and Scholes Option Pricing Model obtained from the “OV” function on Bloomberg, L.P. (“ Bloomberg ”) determined as of the day of consummation of the applicable Fundamental Transaction for pricing purposes and reflecting (A) a risk-free interest rate corresponding to the U.S. Treasury rate for a period equal to the time between the date of the public announcement of the applicable Fundamental Transaction and the Termination Date, (B) an expected volatility equal to the greater of 100% and the 100 day volatility obtained from the HVT function on Bloomberg as of the Trading Day immediately following the public announcement of the applicable Fundamental Transaction, (C) the underlying price per share used in such calculation shall be the sum of the price per share being offered in cash, if any, plus the value of any non-cash consideration, if any, being offered in such Fundamental Transaction and (D) a remaining option time equal to the time between the date of the public announcement of the applicable Fundamental Transaction and the Termination Date, (1) “ Successor Entity ” means the Person (as defined below) (or, if so elected by the Holder, the Parent Entity (as defined below)) formed by, resulting from or surviving any Fundamental Transaction or the Person (or, if so elected by the Holder, the Parent Entity) with which such Fundamental Transaction shall have been entered into, (2) “ Eligible Market ” means the

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NYSE Amex, The NASDAQ Capital Market, The NASDAQ Global Market, The NASDAQ Global Select Market, the New York Stock Exchange or the OTC Bulletin Board (or any successors to any of the foregoing), (3) “ Parent Entity ” of a Person means an entity that, directly or indirectly, controls the applicable Person and whose common stock or equivalent equity security is quoted or listed on an Eligible Market, or, if there is more than one such Person or Parent Entity, the Person or Parent Entity with the largest public market capitalization as of the date of consummation of the Fundamental Transaction. The terms of any agreement pursuant to which a Fundamental Transaction is effected shall include terms requiring any such successor or surviving entity to comply with the provisions of this Section 3(e) and insuring that this Warrant (or any such replacement security) will be similarly adjusted upon any subsequent transaction analogous to a Fundamental Transaction, and (4) “ Person ” means an individual, a limited liability company, a partnership, a joint venture, a corporation, a trust, an unincorporated organization, any other entity and a government or any department or agency thereof.

d) Intentionally Omitted.

e) Subsequent Equity Sales .

i. Except as provided in subsection (e)(iii) hereof, if and whenever the Company shall issue or sell, or is, in accordance with any of subsections (e)(ii)(l) through (e)(ii)(7) hereof, deemed to have issued or sold, any shares of Common Stock for a consideration per share (the “ New Issuance Price ”) less than a price equal to the Exercise Price in effect immediately prior to such issue or sale or deemed issuance or sale (the foregoing a “ Trigger Issuance ”), then, immediately after such Trigger Issuance, the Exercise Price then in effect shall be reduced to an amount equal to the New Issuance Price.

ii. For all purposes of the foregoing (including, without limitation, determining the adjusted Exercise Price and consideration per share under this Section 3(e)), the following subsections (e)(ii)(l) to (e)(ii)(7) shall also be applicable:

(1) Issuance of Rights or Options . In case at any time the Company shall in any manner grant (directly and not by assumption in a merger or otherwise) any warrants or other rights to subscribe for or to purchase, or any options for the purchase of, Common Stock or any stock or security convertible into or exchangeable for Common Stock (such warrants, rights or options being called “ Options ” and such convertible or exchangeable stock or securities being called “ Convertible Securities ”), whether or not such Options or the right to convert or exchange any such Convertible Securities are immediately exercisable, and the price per share for which Common Stock is issuable upon the exercise of such Options or upon the conversion or exchange of such Convertible Securities (determined by dividing (i) the sum (which sum shall constitute the applicable consideration) of (x) the total amount, if any, received or receivable by the Company as consideration for the granting of such Options, plus (y) the aggregate amount of additional consideration payable to the Company upon the exercise of

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all such Options, plus (z), in the case of such Options which relate to Convertible Securities, the aggregate amount of additional consideration, if any, payable upon the issue or sale of such Convertible Securities and upon the conversion or exchange thereof, by (ii) the total maximum number of shares of Common Stock issuable upon the exercise of such Options or upon the conversion or exchange of all such Convertible Securities issuable upon the exercise of such Options) shall be less than the Exercise Price in effect immediately prior to the time of the granting of such Options, then the total number of shares of Common Stock issuable upon the exercise of such Options or upon conversion or exchange of the total amount of such Convertible Securities issuable upon the exercise of such Options shall be deemed to have been issued for such price per share as of the date of granting of such Options or the issuance of such Convertible Securities and thereafter shall be deemed to be outstanding for purposes of adjusting the Exercise Price. Except as otherwise provided in subsection 3(e)(ii)(3), no adjustment of the Exercise Price shall be made upon the actual issue of such Common Stock or of such Convertible Securities upon exercise of such Options or upon the actual issue of such Common Stock upon conversion or exchange of such Convertible Securities.

(2) Issuance of Convertible Securities . In case the Company shall in any manner issue (directly and not by assumption in a merger or otherwise) or sell any Convertible Securities, whether or not the rights to exchange or convert any such Convertible Securities are immediately exercisable, and the price per share for which Common Stock is issuable upon such conversion or exchange (determined by dividing (i) the sum (which sum shall constitute the applicable consideration) of (x) the total amount received or receivable by the Company as consideration for the issue or sale of such Convertible Securities, plus (y) the aggregate amount of additional consideration, if any, payable to the Company upon the conversion or exchange thereof, by (ii) the total number of shares of Common Stock issuable upon the conversion or exchange of all such Convertible Securities) shall be less than the Exercise Price in effect immediately prior to the time of such issue or sale, then the total maximum number of shares of Common Stock issuable upon conversion or exchange of all such Convertible Securities shall be deemed to have been issued for such price per share as of the date of the issue or sale of such Convertible Securities and thereafter shall be deemed to be outstanding for purposes of adjusting the Exercise Price, provided that (a) except as otherwise provided in subsection 3(e)(ii)(3), no adjustment of the Exercise Price shall be made upon the actual issuance of such Common Stock upon conversion or exchange of such Convertible Securities and (b) no further adjustment of the Exercise Price shall be made by reason of the issue or sale of Convertible Securities upon exercise of any Options to purchase any such Convertible Securities for which adjustments of the Exercise Price have been made pursuant to the other provisions of subsection 3(e).

(3) Change in Option Price or Conversion Rate . Upon the happening of any of the following events, namely, if the purchase price provided for in any Option referred to in subsection 3(e)(ii)(l) hereof, the additional consideration, if

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any, payable upon the conversion or exchange of any Convertible Securities referred to in subsections 3(e)(ii)(l) or 3(e)(ii)(2), or the rate at which Convertible Securities referred to in subsections 3(e)(ii)(l) or 3(e)(ii)(2) are convertible into or exchangeable for Common Stock shall change at any time (including, but not limited to, changes under or by reason of provisions designed to protect against dilution), the Exercise Price in effect at the time of such event shall forthwith be readjusted to the Exercise Price which would have been in effect at such time had such Options or Convertible Securities still outstanding provided for such changed purchase price, additional consideration or conversion rate, as the case may be, at the time initially granted, issued or sold. On the termination of any Option for which any adjustment was made pursuant to this subsection 3(e) or any right to convert or exchange Convertible Securities for which any adjustment was made pursuant to this subsection 3(e) (including, without limitation, upon the redemption or purchase for consideration of such Convertible Securities by the Company), the Exercise Price then in effect hereunder shall forthwith be changed to the Exercise Price which would have been in effect at the time of such termination had such Option or Convertible Securities, to the extent outstanding immediately prior to such termination, never been issued.

(4) Stock Dividends . Subject to the provisions of this Section 3(e), in case the Company shall declare a dividend or make any other distribution upon any stock of the Company (other than the Common Stock) payable in Common Stock, Options or Convertible Securities, then any Common Stock, Options or Convertible Securities, as the case may be, issuable in payment of such dividend or distribution shall be deemed to have been issued or sold without consideration.

(5) Calculation of Consideration Received . If any Option and/or Convertible Security and/or Adjustment Right ( as defined below) is issued in connection with the issuance or sale or deemed issuance or sale of any other securities of the Company (as determined by the holder, the “ Primary Security ”, and such Option and/or Convertible Security and/or Adjustment Right, the “ Secondary Securities ”), together comprising one integrated transaction, the consideration per share of Common Stock with respect to such Primary Security shall be deemed to be equal to the difference of (x) the lowest price per share for which one share of Common Stock was issued in such integrated transaction (or was deemed to be issued pursuant to Section 3(e)(1) or 3(e)(2) above, as applicable) solely with respect to such Primary Security, minus (y) with respect to such Secondary Securities, the sum of (I) the Black Scholes Consideration Value of each such Option, if any, (II) the fair market value (as determined by the Holder) or the Black Scholes Consideration Value, as applicable, of such Adjustment Right, if any, and (III) the fair market value (as determined by the Holder) of such Convertible Security, if any, in each case, as determined on a per share basis in accordance with this Section 3(e)(5). “ Black Scholes Consideration Value ” means the value of the applicable Adjustment Rights (as the case may be) as of the date of issuance thereof calculated using the Black Scholes Option Pricing Model obtained from the “OV” function on Bloomberg utilizing (i) an underlying price per share equal to the closing sale price of the Common Stock on

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the Trading Day immediately preceding the public announcement of the execution of definitive documents with respect to the issuance of such Adjustment Rights (as the case may be), (ii) a risk-free interest rate corresponding to the U.S. Treasury rate for a period equal to the remaining term of such Adjustment Rights (as the case may be) as of the date of issuance of such Adjustment Rights (as the case may be), (iii) a zero cost of borrow and (iv) an expected volatility equal to the greater of 100% and the 100 day volatility obtained from the HVT function on Bloomberg (determined utilizing a 365 day annualization factor) as of the Trading Day immediately following the date of issuance of such Adjustment Rights (as the case may be). “Adjustment Right” means any right granted with respect to any securities issued in connection with, or with respect to, any issuance or sale or deemed issuance or sale of shares of Common Stock that could result in a decrease in the net consideration received by the Company in connection with, or with respect to, such securities (including, without limitation, any cash settlement rights, cash adjustment or other similar rights). If any shares of Common Stock, Options or Convertible Securities are issued or sold or deemed to have been issued or sold for cash, the consideration received therefor (for the purpose of determining the consideration paid for such Common Stock, Option or Convertible Security, but not for the purpose of the calculation of the Black Scholes Consideration Value) will be deemed to be the net amount of consideration received or receivable by the Company therefor. If any shares of Common Stock, Options or Convertible Securities are issued or sold for a consideration other than cash (for the purpose of determining the consideration paid for such Common Stock, Option or Convertible Security, but not for the purpose of the calculation of the Black Scholes Consideration Value), the amount of such consideration received or receivable by the Company will be the fair value of such consideration, except where such consideration consists of publicly traded securities, in which case the amount of consideration received by the Company for such securities will be the arithmetic average of the VWAPs of such security for each of the five (5) Trading Days immediately preceding the date of receipt. If any shares of Common Stock, Options or Convertible Securities are issued to the owners of the non-surviving entity in connection with any merger in which the Company is the surviving entity (for the purpose of determining the consideration paid for such Common Stock, Option or Convertible Security, but not for the purpose of the calculation of the Black Scholes Consideration Value), the amount of consideration therefor will be deemed to be the fair value of such portion of the net assets and business of the non-surviving entity as is attributable to such shares of Common Stock, Options or Convertible Securities, as the case may be. The fair value of any consideration other than cash or publicly traded securities will be determined jointly by the Company and the Holder. If such parties are unable to reach agreement within ten (10) days after the occurrence of an event requiring valuation (the “ Valuation Event ”), the fair value of such consideration will be determined within five (5) Trading Days after the tenth (10th) day following such Valuation Event by an independent, reputable appraiser jointly selected by the Company and the Holder. The determination of such appraiser shall be final and binding upon all parties absent manifest error and the fees and expenses of such appraiser shall be borne by the Company.

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(6) Record Date . In case the Company shall take a record of the holders of its Common Stock for the purpose of entitling them (i) to receive a dividend or other distribution payable in Common Stock, Options or Convertible Securities or (ii) to subscribe for or purchase Common Stock, Options or Convertible Securities, then such record date shall be deemed to be the date of the issue or sale of the shares of Common Stock deemed to have been issued or sold upon the declaration of such dividend or the making of such other distribution or the date of the granting of such right of subscription or purchase, as the case may be.

(7) Treasury Shares . The number of shares of Common Stock outstanding at any given time shall not include shares owned or held by or for the account of the Company or any of its wholly-owned subsidiaries, and the disposition of any such shares (other than the cancellation or retirement thereof) shall be considered an issue or sale of Common Stock for the purpose of this subsection (e).

iii. Exempt Issuance . Notwithstanding the foregoing, no adjustment will be made under this paragraph (e) in respect of an Exempt Issuance. For the purposes of this Warrant, “ Exempt Issuance ” means the issuance of (a) shares of Common Stock, Convertible Securities, restricted stock units, Options or common stock equivalents to employees, consultants officers or directors of the Company pursuant to any existing or future stock option, restricted stock, stock purchase or other equity compensation plan or pursuant to employee inducement awards duly adopted for such purpose, by a majority of the non-employee members of the Board of Directors or a majority of the members of a committee of non-employee directors established for such purpose, and the issuance of Common Stock in respect of such Convertible Securities,, restricted stock units, Options or common stock equivalents , (b) securities (including Common Stock and common stock equivalents) upon the exercise, conversion or exchange of securities (including Convertible Securities and Options) issued and outstanding on the date hereof, including the Warrants, provided that such securities have not been amended since date hereof to increase the number of such securities or to decrease the exercise price, exchange price or conversion price of such securities, (c) securities issued pursuant to acquisitions or strategic transactions approved by a majority of the disinterested directors of the Company, but shall not, for the purposes of this clause and (c), include a transaction in which the Company is issuing securities primarily for the purpose of raising capital or to an entity whose primary business is investing in securities and (d) the issuance of securities in a transaction described in Section 3(a) and (b) for which any adjustments shall be to the provisions of such sections.

f) Calculations . All calculations under this Section 3 shall be made to the nearest cent or the nearest 1/100th of a share, as the case may be. For purposes of this

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Section 3, the number of shares of Common Stock deemed to be issued and outstanding as of a given date shall be the sum of the number of shares of Common Stock (excluding treasury shares, if any) issued and outstanding.

g) Notice to Holder .

i. Adjustment to Exercise Price . Whenever the Exercise Price is adjusted pursuant to any provision of this Section 3, the Company shall promptly mail to the Holder a notice setting forth the Exercise Price after such adjustment and setting forth a brief statement of the facts requiring such adjustment.

ii. Notice to Allow Exercise by Holder . After the Issue Date, (A) the Company shall declare a dividend (or any other distribution in whatever form) on the Common Stock, (B) the Company shall declare a special nonrecurring cash dividend on or a redemption of the Common Stock, (C) the Company shall authorize the granting to all holders of the Common Stock rights or warrants to subscribe for or purchase any shares of capital stock of any class or of any rights, (D) the approval of any stockholders of the Company shall be required in connection with any reclassification of the Common Stock, any consolidation or merger to which the Company is a party, any sale or transfer of all or substantially all of the assets of the Company, or any compulsory share exchange whereby the Common Stock is converted into other securities, cash or property, or (E) the Company shall authorize the voluntary or involuntary dissolution, liquidation or winding up of the affairs of the Company, then, in each case, the Company shall cause to be mailed to the Holder at its last address as it shall appear upon the Warrant Register of the Company, at least 20 calendar days prior to the applicable record or effective date hereinafter specified, a notice stating (x) the date on which a record is to be taken for the purpose of such dividend, distribution, redemption, rights or warrants, or if a record is not to be taken, the date as of which the holders of the Common Stock of record to be entitled to such dividend, distributions, redemption, rights or warrants are to be determined or (y) the date on which such reclassification, consolidation, merger, sale, transfer or share exchange is expected to become effective or close, and the date as of which it is expected that holders of the Common Stock of record shall be entitled to exchange their shares of the Common Stock for securities, cash or other property deliverable upon such reclassification, consolidation, merger, sale, transfer or share exchange; provided that the failure to mail such notice or any defect therein or in the mailing thereof shall not affect the validity of the corporate action required to be specified in such notice. To the extent that any notice provided hereunder constitutes, or contains, material, non-public information regarding the Company or any of the Subsidiaries, the Company shall simultaneously file such notice with the Commission pursuant to a Current Report on Form 8-K. The Holder shall remain entitled to exercise this Warrant during the period commencing on the date of such notice to the effective date of the event triggering such notice except as may otherwise be expressly set forth herein.

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Section 4 . Transfer of Warrant .

a) Transferability . This Warrant may not be transferred, sold, or made subject to a security interest or charge, pledged , hypothecated, or otherwise transferred absent compliance with the transfer restrictions set forth above in this Warrant. Upon such compliance with the transfer restrictions and upon the delivery to the Company at its then executive offices of this Warrant along with a duly completed Assignment Form substantially in the form attached hereto (and the required legal opinion, if any), the Company shall execute and deliver a new Warrant in the form of this Warrant (including the legend set forth above on the first page hereof, unless registered under the Securities Act and any applicable securities laws of the several states of the United States (“State Laws”)), but registered in the name of the assignee, to purchase the number of Warrant Shares or that fraction of the Warrant Shares issuable under the original Warrant assigned to the assignee. In case the Holder shall assign this Warrant with respect to fewer than all of the Warrant Shares that may be purchased under this Warrant, the Company shall execute a new warrant in the form of this Warrant for the balance of such Warrant Shares or the remaining fraction of the Warrant Shares issuable under the original Warrant and deliver such new warrant to the Holder. Any transfer or sale or attempted transfer or sale of this Warrant in violation of any provision of this Warrant shall be void, and the Company shall not record such transfer on its books or treat any purported transferee of the Warrant as the owner of the Warrant for any purpose.

b) New Warrants . This Warrant may be divided or combined with other Warrants upon presentation hereof at the aforesaid office of the Company, together with a written notice specifying the names and denominations in which new Warrants are to be issued, signed by the Holder or its agent or attorney. Subject to compliance with Section 4(a), as to any transfer which may be involved in such division or combination, the Company shall execute and deliver a new Warrant or Warrants in exchange for the Warrant or Warrants to be divided or combined in accordance with such notice. All Warrants issued on transfers or exchanges shall be dated the initial issuance date set forth on the first page of this Warrant and shall be identical with this Warrant except as to the number of Warrant Shares issuable pursuant thereto.

c) Warrant Register . The Company shall register this Warrant, upon records to be maintained by the Company for that purpose (the “ Warrant Register ”), in the name of the record Holder hereof from time to time. The Company may deem and treat the registered Holder of this Warrant as the absolute owner hereof for the purpose of any exercise hereof or any distribution to the Holder, and for all other purposes, absent actual notice to the contrary. Upon thirty (30) days notice to the Holder, the Company may appoint a warrant agent to maintain the Warrant Register.

d) Representation by the Holder . The Holder represents and covenants to the Company by acceptance of this Warrant, as follows:

i. That the Holder is not a U.S. Person (as defined in Rule 902 of Regulation S promulgated under the Securities Act) and is not acquiring the Warrant for the account or benefit of any U.S. Person.

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ii. The Holder acquired this Warrant from the Company and will acquire Warrant Shares issuable upon exercise hereof, for its own account, for investment purposes only and not with a view to the resale and distribution thereof, in whole or in part.

iii. The Holder shall comply with the transfer restrictions set out above and in the Loan Commitment Letter between the Holder and the Company (the “Commitment Letter”) (including, without limitation, Schedule C attached thereto and made a part thereof) and the Holder understands that this Warrant and the Warrant Shares issuable on exercise hereof must be held indefinitely unless subsequently registered under the Securities Act and qualified under any applicable State Laws, or unless exemptions from registration and qualification are otherwise available.

iv. The Holder acknowledges and agrees that hedging transactions involving this Warrant or the Warrant Shares may not be conducted unless conducted in compliance with law.

Section 5 . Compliance with Securities Laws . This Warrant and the Warrant Shares have not been registered under the Securities Act, or qualified under State Laws. The Holder is aware that the issuance of this Warrant and the issuance of the Warrant Shares are being made in reliance on Regulation S under the Securities Act. This Warrant and the Warrant Shares have been purchased for investment and not with a view to distribution or resale, and may not be assigned, sold or made subject to a security interest, pledged, hypothecated, or otherwise transferred without an effective registration statement for such Warrant or Warrant Shares under the Securities Act and qualification under State Laws, pursuant to an exemption from registration and qualification, or an opinion of counsel satisfactory to the Company that such registration and qualification are not required. Any Warrant Shares issued upon the exercise of this Warrant (unless pursuant to an effective registration statement under the Act) shall bear the following legend:

THIS SECURITY HAS NOT BEEN AND WILL NOT REREGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS. THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, AGREES FOR THE BENEFIT OF THE COMPANY THAT THIS SECURITY MAY NOT BE OFFERED, SOLD, PLEDGED, OR OTHERWISE TRANSFERRED BY SUCH HOLDER PRIOR TO THE LATER OF (X) SIX MONTHS FOLLOWING THE ISSUANCE HEREOF OR (Y) IF APPLICABLE, THREE MONTHS AFTER IT CEASES TO BE AN AFFILIATE, OTHER THAN (1) TO THE COMPANY, (2) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT AND IN ACCORDANCE WITH ANY APPLICABLE LAWS OF ANY STATE OF THE UNITED STATES, (3) IN AN OFFSHORE TRANSACTION COMPLYING WITH REGULATION S UNDER THE SECURITIES ACT, (4) PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT PROVIDED BY RULE 144, IF APPLICABLE, UNDER THE SECURITIES ACT OR (5) IN A TRANSACTION THAT DOES NOT REQUIRE REGISTRATION UNDER THE SECURITIES

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ACT BUT IS IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS AND IN RELATION TO WHICH THE HOLDER HAS FURNISHED TO THE COMPANY AN OPINION TO SUCH EFFECT FROM COUNSEL OF RECOGNISED STANDING IN FORM AND SUBSTANCE SATISFACTORY TO THE COMPANY PRIOR TO SUCH OFFER, SALE, PLEDGE OR TRANSFER. THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, REPRESENTS AND AGREES FOR THE BENEFIT OF THE COMPANY THAT IT IS A NON-U.S. PERSON, AND ACKNOWLEDGES THAT HEDGING TRANSACTIONS INVOLVING THESE SECURITIES MAY NOT BE CONDUCTED UNLESS CONDUCTED IN COMPLIANCE WITH THE SECURITIES ACT.

Section 6 . Miscellaneous .

a) No Rights as Stockholder Until Exercise . This Warrant does not entitle the Holder to any voting rights, dividends or other rights as a stockholder of the Company prior to the exercise hereof.

b) Loss, Theft, Destruction or Mutilation of Warrant . The Company covenants that upon receipt by the Company of evidence reasonably satisfactory to it of the loss, theft, destruction or mutilation of this Warrant or any stock certificate relating to the Warrant Shares, and in case of loss, theft or destruction, of indemnity or security reasonably satisfactory to it (which, in the case of the Warrant, shall not include the posting of any bond), and upon surrender and cancellation of such Warrant or stock certificate, if mutilated, the Company will make and deliver a new Warrant or stock certificate of like tenor and dated as of such cancellation, in lieu of such Warrant or stock certificate.

c) Saturdays, Sundays, Holidays, etc . If the last or appointed day for the taking of any action or the expiration of any right required or granted herein shall not be a Business Day, then, such action may be taken or such right may be exercised on the next succeeding Business Day.

d) Authorized Shares .

The Company covenants that, during the period the Warrant is outstanding, it will reserve from its authorized and unissued Common Stock a sufficient number of shares to provide for the issuance of the Warrant Shares upon the exercise of any purchase rights under this Warrant. The Company further covenants that its issuance of this Warrant shall constitute full authority to its officers who are charged with the duty of executing stock certificates to execute and issue the necessary certificates for the Warrant Shares upon the exercise of the purchase rights under this Warrant. The Company will take all such reasonable action as may be necessary to assure that such Warrant Shares may be issued as provided herein without violation of any applicable law or regulation, or of any requirements of the Trading Market upon which the Common Stock may be listed. The Company covenants that all Warrant Shares which may be issued upon the exercise of the purchase rights represented by this

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Warrant will, upon exercise of the purchase rights represented by this Warrant and payment for such Warrant Shares in accordance herewith, be duly authorized, validly issued, fully paid and nonassessable and free from all taxes, liens and charges created by the Company in respect of the issue thereof (other than taxes in respect of any transfer occurring contemporaneously with such issue).

Except and to the extent as waived or consented to by the Holder, the Company shall not by any action, including, without limitation, amending its certificate of incorporation or through any reorganization, transfer of assets, consolidation, merger, dissolution, issue or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such actions as may be necessary or appropriate to protect the rights of Holder as set forth in this Warrant against impairment. Without limiting the generality of the foregoing, the Company will (i) not increase the par value of any Warrant Shares above the amount payable therefor upon such exercise immediately prior to such increase in par value, (ii) take all such action as may be necessary or appropriate in order that the Company may validly and legally issue fully paid and nonassessable Warrant Shares upon the exercise of this Warrant and (iii) use commercially reasonable efforts to obtain all such authorizations, exemptions or consents from any public regulatory body having jurisdiction thereof, as may be, necessary to enable the Company to perform its obligations under this Warrant.

Before taking any action which would result in an adjustment in the number of Warrant Shares for which this Warrant is exercisable or in the Exercise Price, the Company shall obtain all such authorizations or exemptions thereof, or consents thereto, as may be necessary from any public regulatory body or bodies having jurisdiction thereof.

e) Jurisdiction . All questions concerning the construction, validity, enforcement and interpretation of this Warrant shall be determined in accordance with the laws of the State of Delaware.

f) Restrictions . The Holder acknowledges that the Warrant Shares acquired upon the exercise of this Warrant, if not registered, and the Holder does not utilize cashless exercise, will have restrictions upon resale imposed by state and federal securities laws.

g) Nonwaiver and Expenses . No course of dealing or any delay or failure to exercise any right hereunder on the part of Holder shall operate as a waiver of such right or otherwise prejudice Holder’s rights, powers or remedies. Without limiting any other provision of this Warrant, if the Company willfully and knowingly fails to comply with any provision of this Warrant, which results in any material damages to the Holder, the Company shall pay to Holder such amounts as shall be sufficient to cover any costs and expenses including, but not limited to, reasonable attorneys’ fees, including those of appellate proceedings, incurred by Holder in collecting any amounts due pursuant hereto or in otherwise enforcing any of its rights, powers or remedies hereunder.

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h) Notices . The Company shall provide Holder with prompt written notice of all actions taken pursuant to this Warrant. Whenever notice is required to be given under this Warrant, unless otherwise provided herein, such notice shall be given in writing, will be mailed (a) if within the domestic United States by first-class registered or certified airmail, or nationally recognized overnight express courier, postage prepaid, or by facsimile or (b) if delivered from outside the United States, by International Federal Express or facsimile, and (c) will be deemed given (i) if delivered by first-class registered or certified mail domestic, three Business Days after so mailed, (ii) if delivered by nationally recognized overnight carrier, one Business Day after so mailed, (iii) if delivered by International Federal Express, two Business Days after so mailed and (iv) if delivered by facsimile, upon electronic confirmation of receipt, and will be delivered and addressed as follows:

(i) if to the Company, to:

Clean Diesel Technologies Inc.

4567 Telephone Road, Suite 100

Ventura, California 93003

Attention: Chief Financial Officer

Facsimile:

With Copies to:

DLA LLP (US)

2525 E. Camelback Rd, Suite 1000

Phoenix, AZ 85016

Attention: Steven Pidgeon

Facsimile:

(ii) if to the Holder, at the address of the Holder appearing on the books of the Company.

i) Limitation of Liability . No provision hereof, in the absence of any affirmative action by Holder to exercise this Warrant to purchase Warrant Shares, and no enumeration herein of the rights or privileges of Holder, shall give rise to any liability of Holder for the purchase price of any Common Stock or as a stockholder of the Company, whether such liability is asserted by the Company or by creditors of the Company.

j) Remedies . The Holder, in addition to being entitled to exercise all rights granted by law, including recovery of damages, will be entitled to specific performance of its rights under this Warrant. The Company agrees that monetary damages would not be adequate compensation for any loss incurred by reason of a breach by it of the provisions of this Warrant and hereby agrees to waive and not to assert the defense in any action for specific performance that a remedy at law would be adequate.

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k) Successors and Assigns . Subject to applicable securities laws, this Warrant and the rights and obligations evidenced hereby shall inure to the benefit of and be binding upon the successors and permitted assigns of the Company and the successors and permitted assigns of Holder. The provisions of this Warrant are intended to be for the benefit of any Holder from time to time of this Warrant and shall be enforceable by the Holder or holder of Warrant Shares.

l) Amendment . This Warrant may be modified or amended or the provisions hereof waived with the written consent of the Company and the Holder.

m) Severability . Wherever possible, each provision of this Warrant shall be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Warrant shall be prohibited by or invalid under applicable law, such provision shall be ineffective to the extent of such prohibition or invalidity, without invalidating the remainder of such provisions or the remaining provisions of this Warrant.

n) Headings . The headings used in this Warrant are for the convenience of reference only and shall not, for any purpose, be deemed a part of this Warrant.

********************

(Signature Page Follows)

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IN WITNESS WHEREOF, the Company has caused this Warrant to be executed by its officer thereunto duly authorized as of the date first above indicated.

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NOTICE OF EXERCISE

To: CLEAN DIESEL TECHNOLOGIES, INC.

(1) The undersigned hereby elects to purchase                  Warrant Shares of the Company pursuant to the terms of the attached Warrant (only if exercised in full), and tenders herewith payment of the exercise price in full, together with all applicable transfer taxes, if any.

(2) Payment shall take the form of in lawful money of the United States; or

(3) Please issue a certificate or certificates representing said Warrant Shares in the name of the undersigned or in such other name as is specified below:

The Warrant Shares shall be delivered to the following DWAC Account Number or by physical delivery of a certificate to:

[SIGNATURE OF HOLDER]

ASSIGNMENT FORM

(To assign the foregoing warrant, execute

this form and supply required information.

Do not use this form to exercise the warrant.)

FOR VALUE RECEIVED, [            ] all of or [                ] shares of the foregoing Warrant and all rights evidenced thereby are hereby assigned to

NOTE: The signature to this Assignment Form must correspond with the name as it appears on the face of the Warrant, without alteration or enlargement or any change whatsoever, and must be guaranteed by a bank or trust company. Officers of corporations and those acting in a fiduciary or other representative capacity should file proper evidence of authority to assign the foregoing Warrant.

TRANSFER RESTRICTIONS

The Warrant and Warrant Shares (collectively, the “Warrant Securities”) have not been registered under the U.S. Securities Act of 1933, as amended (the “Securities Act”), and may not be offered or sold to or for the account or benefit of “U.S. Persons” (as defined in Rule 902 of Regulation S promulgated under the Securities Act), except pursuant to Regulation S, the registration requirements of the Securities Act or an exemption from the registration requirements of the Securities Act.

Accordingly, the Warrant Securities are being placed outside the U.S. to non-U.S. Persons in an offshore transaction in reliance on Regulation S under the Securities Act. The terms “United States” and “U.S. Person” have the respective meanings given to those terms in Regulation S under the Securities Act.

Each holder of Warrant Securities will be deemed to have represented and agreed as follows:

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D. It understands that in any resale and transfer of Warrant Securities it will, and each subsequent holder thereof is required to, notify any purchaser of Warrant Securities of the resale restrictions referred to above, if then applicable. This notification requirement will be satisfied by virtue of the fact that the following legend will be placed on the certificates representing the Warrant Shares, unless otherwise agreed to by the Company:

THIS SECURITY HAS NOT BEEN AND WILL NOT REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS. THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, AGREES FOR THE BENEFIT OF THE COMPANY THAT THIS SECURITY MAY NOT BE OFFERED, SOLD, PLEDGED, OR OTHERWISE TRANSFERRED BY SUCH HOLDER PRIOR TO THE LATER OF THE (X) SIX MONTHS FOLLOWING THE ISSUANCE HEREOF OR (Y) IF APPLICABLE, THREE MONTHS AFTER IT CEASES TO BE AN AFFILIATE, OTHER THAN (1) TO THE COMPANY, (2) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT AND IN ACCORDANCE WITH ANY APPLICABLE LAWS OF ANY STATE OF THE UNITED STATES, (3) IN AN OFFSHORE TRANSACTION COMPLYING WITH REGULATION S UNDER THE SECURITIES ACT, (4) PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT PROVIDED BY RULE 144, IF APPLICABLE, UNDER THE SECURITIES ACT OR (5) IN A TRANSACTION THAT DOES NOT REQUIRE REGISTRATION UNDER THE SECURITIES ACT BUT IS IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS AND IN RELATION TO WHICH THE HOLDER HAS FURNISHED TO THE COMPANY AN OPINION TO SUCH EFFECT FROM COUNSEL OF RECOGNISED STANDING IN FORM AND SUBSTANCE SATISFACTORY TO THE COMPANY PRIOR TO SUCH OFFER, SALE, PLEDGE OR TRANSFER. THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, REPRESENTS AND AGREES FOR THE BENEFIT OF THE COMPANY THAT IT IS A NON-U.S. PERSON, AND ACKNOWLEDGES THAT HEDGING TRANSACTIONS INVOLVING THESE SECURITIES MAY NOT BE CONDUCTED UNLESS CONDUCTED IN COMPLIANCE WITH THE SECURITIES ACT.

E. It acknowledges that the foregoing restrictions apply to holders of beneficial interests in the Warrant Securities as well as to holders of Warrant Securities.

F. It acknowledges that it shall not engage in any hedging transactions involving the Warrant Securities unless in compliance with the Securities Act.

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G. It is a “Qualified Investor” within the meaning of Section 86 of the Financial Services and Markets Act 2000 and an “investment professional” within the meaning of Article 19 of the FSMA 2000 (Financial Promotion) Order 2005.

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EXHIBIT 99.3

FOR IMMEDIATE RELEASE

CDTi Announces Closing of Underwritten Public Offering of

Common Stock and Warrants

Ventura, CA – July 3, 2013 — Clean Diesel Technologies, Inc. (NASDAQ:CDTI) (“CDTi” or the “Company”) announced today that it has closed its previously announced offering of shares and warrants (the “Offering”). The Offering was fully subscribed and the underwriter partially exercised its over-allotment option. A total of 1,730,000 shares of common stock were sold at a price of $1.245 per share and warrants to purchase up to 865,000 shares were sold at a price per warrant of $0.01, including 130,000 shares and 65,000 warrants upon partial exercise of the underwriter’s over-allotment option. The warrants have an exercise price of $1.25 per share, and are exercisable immediately for a period of five years. CDTi received net proceeds from the Offering of approximately $1.7 million after deducting discounts and commissions to the underwriter and estimated offering expenses. The Company intends to use the net proceeds from the offering for general corporate purposes, which may include working capital, general and administrative expenses, capital expenditures and implementation of its strategic priorities.

Roth Capital Partners, LLC acted as Sole Manager for the Offering.

In addition, concurrent with the Offering, CDTi converted $235,000 of principal and interest due June 30, 2013, pursuant to loans made to the Company by one of its principal lenders and largest shareholders, to common stock and warrants, and agreed to sell $100,000 of common stock to one of its directors in a private placement.

The Offering was made pursuant to a shelf registration statement on Form S-3, including a base prospectus dated May 21, 2012, previously filed and declared effective by the Securities and Exchange Commission (the “SEC”). A copy of the final prospectus supplement related to the Offering has been filed with the SEC and is available on the SEC’s website located at http://www.sec.gov. Alternatively, a copy of the prospectus supplement and related base prospectus may be obtained from Roth Capital Partners, LLC at 888 San Clemente Drive, Newport Beach, CA 92660, or by telephone at (800) 678-9147, or by e-mail at rothecm@roth.com.

This press release is neither an offer to sell nor a solicitation of an offer to buy any of these securities and shall not constitute an offer, solicitation or sale in any jurisdiction in which such offer, solicitation or sale is unlawful.

The securities sold in the private placement are not registered under the Securities Act of 1933, as amended, or any state securities laws and may not be offered or sold in the United States absent registration or an applicable exemption from the registration requirement of such Act and applicable state securities laws.

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CDTi * 4567 Telephone Road, Suite 100 * Ventura CA 93003 * 805-639-9458

About CDTi

CDTi is a global manufacturer and distributor of emissions control systems and products, focused on the heavy duty diesel and light duty vehicle markets. CDTi is headquartered in Ventura, California and currently has operations in the U.S., Canada, France, Japan and Sweden.

Forward-Looking Statements Safe Harbor

This press release contains forward-looking statements regarding future events and the Company’s future results that are subject to the safe harbors created under the Securities Act of 1933, as amended, and the Securities Exchange Act of 1934, as amended. These statements are based on current expectations, estimates, forecasts, and projections about the market condition, the industry in which the Company operates and the beliefs and assumptions of the Company’s management. Words such as “expects,” “anticipates,” “targets,” “goals,” “projects,” “intends,” “plans,” “believes,” “seeks,” “estimates,” “continues,” “may,” variations of such words, and similar expressions, are intended to identify such forward-looking statements. Forward-looking statements are subject to a number of assumptions, risks and uncertainties, many of which are beyond our control, including such factors as discussed under the caption “Risk Factors” in our final prospectus supplement filed with the SEC and our Annual Report on Form 10-K for the fiscal year ended December 31, 2012, and our other periodic and current reports filed with the SEC and available on www.sec.gov . Readers are cautioned that forward-looking statements are not guarantees of future performance and that actual results or developments may differ materially from those expressed or implied in the forward-looking statements. Any forward-looking statement made by us in this release is based only on information currently available to us and speaks only as of the date on which it is made. We undertake no obligation to publicly update any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future developments or otherwise.

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Contact Information:

Kevin M. McGrath

Cameron Associates, Inc.

Tel: +1 (212) 245-4577

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CDTi * 4567 Telephone Road, Suite 100 * Ventura CA 93003 * 805-639-9458