PATENT AND TRADEMARK SECURITY AGREEMENT

EXHIBIT 10.3.4

PATENT AND TRADEMARK SECURITY AGREEMENT

BY BSST IN FAVOR OF

COMERICA BANK DATED AS OF NOVEMBER 14, 2002

PATENT AND TRADEMARK SECURITY AGREEMENT

PATENT AND TRADEMARK SECURITY AGREEMENT, dated as of November 14, 2002, made by BSST LLC, a Delaware limited liability company (the “Grantor”) in favor of COMERICA BANK, a Michigan banking corporation (the “Bank”).

WITNESSETH:

WHEREAS, Amerigon Incorporated (“Borrower”) is a party to the Credit Agreement dated as of the date hereof (the “Credit Agreement”) between the Bank and Borrower;

WHEREAS, Grantor has guaranteed certain obligations of Borrower to the Bank under a Guaranty dated as of the date hereof (as amended or modified from time to time, the “Guaranty”);

WHEREAS, the Grantor owns certain Trademarks (as defined below) and Trademark Licenses (as defined below) listed on Schedule I attached hereto;

WHEREAS, the Grantor owns certain Patents (as defined below) and Patent Licenses (as defined below) listed on Schedule II attached hereto;

WHEREAS, it is a condition precedent to the obligation of the Bank to make credit advances to the Borrower under the Credit Agreement that the Grantor shall have executed and delivered this Agreement to the Bank;

NOW, THEREFORE, in consideration of the premises and to induce the Bank to enter into the Credit Agreement and to make advances to the Borrower thereunder and under the Note (as defined below), the Grantor hereby agrees with the Bank, as follows:

1. Defined Terms .

(a) Unless otherwise defined herein, capitalized terms defined in the Credit Agreement are used herein as defined therein. The following terms shall have the following meanings:

“ Agreement ”: this Patent and Trademark Security Agreement, as the same may be amended, supplemented, waived or otherwise modified from time to time.

“ BSST Patent and Trademark Collateral ”: as defined in Section 2 of this Agreement.

“ Code ”: the Uniform Commercial Code as from time to time in effect in the State of Michigan.

“ Event of Default ”: any default or event of default described in Section 7 of the Credit Agreement and lapse of any applicable grace and/or cure periods.

“ General Intangibles ” as defined in the Code, including, without limitation, all Patents and Trademarks now or hereafter owned by the Grantor to the extent such Patents and Trademarks would be included in General Intangibles under the Code.

“ Lien ”: any lien, security interest, pledge, encumbrance or other similar charge, whether voluntary or involuntary and however created.

“ Note ”: the collective reference to the notes issued pursuant to the Credit Agreement and any modifications, amendments, renewals or extensions thereof.

“ Obligations ”: all obligations and liabilities of the Grantor to the Bank, whether direct or indirect, absolute or contingent, due or to become due, or now existing or hereafter incurred, including, without limitation, obligations and liabilities which may arise under, out of, or in connection with, the Guaranty or any other document made, delivered or given by Grantor to the Bank in connection therewith, in each case whether on account of principal, interest, reimbursement obligations, fees, indemnities, costs, expenses or otherwise (including, without limitation, all reasonable fees and disbursements of counsel to the Bank).

“ Patent License ”: all United States license agreements with any other person in connection with any of the Patents or such other person’s patents, whether the Grantor is a licensor or a licensee under any such license agreement, including, without limitation, the license agreements listed on Schedule II hereto and made a part hereof, subject, in each case, to the terms of such license agreements and the right to prepare for sale, sell and advertise for sale, all inventory now or hereafter covered by such licenses.

“ Patents ”: all United States patents, patent applications including, without limitation, all patents and patent applications identified in Schedule II attached hereto and made a part hereof, and including without limitation (a) all inventions and improvements described and claimed therein, (b) the right to sue or otherwise recover for any and all past, present and future infringements and misappropriations thereof, (c) all income, royalties, damages and other payments now and hereafter due and/or payable with respect thereto (including, without limitation, payments under all licenses entered into in connection therewith, and damages and payments for past or future infringements thereof), and (d) all rights corresponding thereto in the United States and all reissues, divisions, continuations, continuations-in-part, substitutes, renewals,, and extensions thereof, all improvements thereon, and all other rights of any kind whatsoever of the Grantor accruing thereunder or pertaining thereto (Patents and Patent Licenses being, collectively, the “Patent Collateral”).

“ Trademark License ”: all United States license agreements with any other person in connection with any of the Trademarks or such other person’s names or trademarks, whether the Grantor is a licensor or a licensee under any such license agreement, including, without limitation, the license agreements listed on Schedule I hereto and made a part hereof, subject, in each case, to the terms of such license agreements, and the right to prepare for sale, sell and advertise for sale, all inventory now or hereafter covered by such licenses.

“ Trademarks ”: all trademarks, service marks, trademark and service mark registrations, and applications for trademark or service mark registrations (except for “intent to use” applications for trademark or service mark registrations filed pursuant to Section 1(b) of the Lanham Act, unless and until an Amendment to Allege Use or a Statement of Use under Sections 1(c) and 1(d) of said Act has been filed), and any renewals thereof, including, without limitation, each registration and application identified in Schedule I attached hereto and made a part hereof, and including without limitation (a) the right to sue or otherwise recover for any and all past, present and future infringements and misappropriations thereof, (b) all income, royalties, damages and other payments now and hereafter due and/or payable with respect thereto (including, without limitation, payments under all licenses entered into in connection therewith, and damages and payments for past or future infringements thereof) and (c) all rights corresponding thereto in the United States and all other rights of any kind whatsoever of the Grantor accruing thereunder or pertaining thereto, together in each case with the goodwill of the business connected with the use of, and symbolized by, each such trademark, service mark, trade name, trade dress or other indicia of trade origin (Trademarks and Trademark Licenses being, collectively, the “ Trademark Collateral ”).

(b) The words “hereof,” “herein” and “hereunder” and words of similar import when used in this Agreement shall refer to this Agreement as a whole and not to any particular provision of this Agreement, and section and paragraph references are to this Agreement unless otherwise specified.

(c) The meanings given to terms defined herein shall be equally applicable to both the singular and plural forms of such terms.

2. Grant of Security Interest . As collateral security for the prompt and complete payment and performance when due (whether at the stated maturity, by acceleration or otherwise) of the Obligations, the Grantor hereby assigns, pledges and grants to the Bank a security interest in all of the following property now owned or at any time hereafter acquired by the Grantor or in which the Grantor now has or at any time in the future may acquire any right, title or interest (collectively, the “ BSST Patent and Trademark Collateral ”):

Notwithstanding anything herein to the contrary, “BSST Patent and Trademark Collateral” shall not include any general intangible that is the subject of a written agreement which specifically prohibits assignment thereof or grant of a security interest therein but only to the extent of such prohibition, and only to the extent that the terms and provisions of such written agreement, document or instrument creating or evidencing such property or any rights relating thereto expressly prohibit the granting of a security interest therein or condition the granting of a security interest therein on the consent of a third party whose consent has not been obtained or would cause, or allow a third party to cause, forfeiture of such property upon the granting of a security interest therein or a breach under any written agreement relating thereto; provided, however, that immediately upon the effectiveness, lapse or termination of such provision, the BSST Patent and Trademark Collateral shall include, and Grantor shall be deemed to have granted a security interest in all such general intangibles as if such term had never been in effect.

3. Grantor Remains Liable; Limitations on Bank’s Obligations . Anything herein to the contrary notwithstanding, (a) the Grantor shall remain liable under the contracts and agreements included in the BSST Patent and Trademark Collateral to the extent set forth therein to perform all of its duties and obligations thereunder to the same extent as if this Agreement had not been executed, (b) the exercise by the Bank of any of the rights hereunder shall not release the Grantor from any of its duties or obligations under the contracts and agreements included in the BSST Patent and Trademark Collateral, and (c) the Bank shall not have any obligation or liability under the contracts and agreements included in the BSST Patent and Trademark Collateral by reason of this Agreement, nor shall the Bank be obligated to perform any of the obligations or duties of the Grantor thereunder or to take any action to collect or enforce any claim for payment assigned hereunder.

4. Representations and Warranties . The Grantor represents and warrants as follows:

(a) Title; No Other Liens . Except for the Liens granted to the Bank and the Permitted Liens under the Credit Agreement, the Grantor is (or, in the case of after-acquired BSST Patent and Trademark Collateral, will be) the sole, legal and beneficial owner of the entire right, title and interest in and to the Trademarks set forth on Schedule I hereto and the Patents set forth in Schedule II hereto free and clear of any and all Liens. No security agreement, financing

statement or other public notice similar in effect with respect to all or any part of the BSST Patent and Trademark Collateral is on file or of record in any public office (including, without limitation, the United States Patent and Trademark Office) except such as may have been filed in favor of the Bank pursuant to this Agreement and Permitted Liens.

(b) Perfected First Priority Liens .

(c) Consents . Except as disclosed in Schedule III attached hereto, no consent of any party (other than such Grantor) to any Patent License or Trademark License constituting BSST Patent and Trademark Collateral is required, or purports to be required, to be obtained by or on behalf of such Grantor in connection with the execution, delivery and performance of this Agreement that has not been obtained. Each Patent License and Trademark License constituting BSST Patent and Trademark Collateral is in full force and effect and constitutes a valid and legally enforceable obligation of the Grantor and (to the knowledge of the Grantor) each other party thereto except as enforceability may be limited by bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the enforcement of creditor’s rights generally and by general equitable principles (whether enforcement is sought by proceedings in equity or at law). No consent or authorization of, filing with or other act by or in respect of any governmental authority is required in connection with the execution, delivery, performance, validity or enforceability of any of the Patent Licenses or Trademark Licenses by any party thereto other than those which have been duly obtained, made or performed and are in full force and effect. Neither the Grantor nor (to the knowledge of the Grantor) any other party to any Patent License or Trademark License constituting BSST Patent and Trademark Collateral is in default in the performance or observance of any of the terms thereof, except for such defaults as would not reasonably be expected, in the aggregate, to have a material adverse effect on the value of the BSST Patent and Trademark Collateral. The right, title and interest of the Grantor in, to and under each Patent License and Trademark License constituting BSST Patent and Trademark Collateral are not subject to any material defense, offset, counterclaim or claim.

(d) Schedules I and II are Complete; All Filings Have Been Made . Set forth in Schedules I and H is a complete and accurate list of the Trademarks and Patents owned by the Grantor as of the date hereof. The Grantor has made all necessary filings and recordations to protect and maintain its interest in the Trademarks and Patents set forth in Schedules I and II, including, without limitation, all necessary filings and recordings, and payments of all maintenance fees, in the United States Patent and Trademark Office to the extent such Trademarks and Patents are material to the Grantor’s business. Set forth in Schedules I and II is a complete and accurate list of all of the material Trademark Licenses and Patent Licenses owned by the Grantor as of the date hereof.

(e) The Trademarks and Trademark Licenses are Subsisting and Not Adjudged Invalid . As of the date hereof, each material trademark registration and trademark application of the Grantor set forth in Schedule I is subsisting as of the date hereof and has not been adjudged invalid, unregisterable or unenforceable, in whole or in part, and, to the best of the Grantor’s knowledge, is valid, registrable and enforceable. As of the date hereof, each of the Trademark Licenses set forth in Schedule I is validly subsisting and has not been adjudged invalid or unenforceable, in whole or in part, and, to the best of the Grantor’s knowledge, is valid and enforceable. As of the date hereof, the Grantor has notified the Bank in writing of all uses of any item of Trademark Collateral of which the Grantor is aware which could reasonably be expected to lead to such item becoming invalid or unenforceable, including unauthorized uses by third parties and uses which were not supported by the goodwill of the business connected with such BSST Patent and Trademark Collateral.

(f) The Patent and Patent Licenses are Subsisting and Not Adjudged Invalid . As of the date hereof, each material Patent and patent application of the Grantor set forth in Schedule II is subsisting and has not been adjudged invalid, unpatentable or unenforceable, in whole or in part, and, to the best of the Grantor’s knowledge, is valid, patentable and enforceable. As of the date hereof, each of the material Patent Licenses set forth in Schedule II is validly subsisting and has not been adjudged invalid or unenforceable, in whole or in part, and, to the best of the Grantor’s knowledge, is valid and enforceable. As of the date hereof, the Grantor has notified the Bank in writing of all uses of any item of Patent Collateral material to the Grantor’s business of which the Grantor is aware which could reasonably be expected to lead to such item becoming invalid or unenforceable.

(g) No Previous Assignments or Releases . Except as expressly permitted by the Credit Agreement and such as may have been filed in favor of Bank relating to this Agreement, no effective financing statement or other instrument similar in effect covering all or any part of the BSST Patent and Trademark Collateral is on file in any filing or recording office.

(h) Proper Statutory Notice . The Grantor has marked its products with the trademark registration symbol the numbers of all appropriate patents, the common law trademark symbol or the designation “patent pending,” as the case may be, to the extent that it is reasonably and commercially practicable, in all material respects.

(i) No Knowledge of Claims Likely to Arise . After reasonably inquiry, Grantor is not aware of any pending or threatened claim by any third party that any of the Borrower Patent and Trademark Collateral owned, held or used by such Grantor is invalid or unenforceable.

(j) No Knowledge of Existing or Threatened Claims . No claim has been made and is continuing or, to the best of the Grantor’s knowledge, threatened that the use by the Grantor of any item of material BSST Patent and Trademark Collateral is invalid or unenforceable or that the use by the Grantor of any material BSST Patent and Trademark Collateral does or may violate the rights of any person. To the best of the Grantor’s knowledge, there is currently no infringement or unauthorized use of any item of material BSST Patent and Trademark Collateral contained on Schedules I and II.

5. Covenants . The Grantor covenants and agrees with the Bank that, from and after the date of this Agreement until the payment in full of the Obligations:

(a) Further Documentation; Pledge of Instruments and Chattel Paper . At any time and from time to time, upon the written request of the Bank or the Grantor, as the case may be, and at the sole expense of the Grantor, the Grantor or the Bank, as the case may be, will promptly and duly execute and deliver such further instruments and documents and take such further action as the Bank or the Grantor may reasonably request for the purpose of obtaining or preserving the full benefits of this Agreement and of the rights and powers herein granted, including, without limitation, the filing of any financing or continuation statements under the Code in effect in any jurisdiction with respect to the Liens created hereby. The Grantor also hereby authorizes the Bank to file any such financing or continuation statement without the signature of the Gr