**Exhibit 10.19.1****Certain information in this document, marked by brackets, has been omitted and filedseparately with the Securities and Exchange Commission. Confidential treatment hasbeen requested with respect to the omitted portions.****AMENDMENT NO. 1 TO LICENSE AGREEMENT**     This Amendment No. 1 (“Amendment No. 1”) amends that certain License Agreement effective March28, 2002 (the “Agreement”) entered by and between Maxygen, Inc. (“MUS”) and Codexis, Inc.(“Codexis”), and shall be effective as of September 13, 2002 (the “Amendment Date”). MUS andCodexis hereby amend the License Agreement as follows:1. Article 1 is amended by the addition of the following new definitions:     1.54 **“Category”**shall mean each of the identified categories listed on Exhibit G.     1.55 **“Reserved SubField Termination Date”**shall mean the period commencing on theAmendment Date and ending on the later of (i) five (5) years after the Amendment Date, or(ii) a Separation Event.     1.56 **“Reserved SubFields”**shall mean, in the period from the Amendment Date until theReserved SubField Termination Date, the subject matter within the SubFields. It isunderstood and agreed that (i) as of the Reserved SubField Termination Date, one or more ofthe SubFields may become part of the Codexis Field pursuant to Section 2.1.6(d), and (ii) asof the Reserved SubField Termination Date, the Reserved SubFields (including each Categoryand SubField) shall be terminated, and shall have no content or force or effect for theremainder of the term of the Agreement.     1.57 **“Scheduled Product”**shall mean any chemical described on Exhibit F.     1.58 **“SubField”**shall mean each of the identified SubFields listed on Exhibit G.     1.59 **“Supplemental Product”**shall mean (a) any chemical within a Category with regardto which Category Codexis conducts a research project meeting the criteria set forth inSection 2.1.6(a) prior to the Reserved SubField Termination Date and (b) each chemical thatis within a SubField that becomes part of the Codexis Field as of the Reserved SubFieldTermination Date pursuant to Section 2.1.6(d).2. Section 1.10 is amended to provide in its entirety, as follows:     **1.10 “Bulk Production”**shall mean production by Codexis via enzymatic catalysis (usingan Enzyme Product or a Biocatalyst) or fermentation of:          (a) any Enzyme Product or Biocatalyst for sale to a Third Party (other than anAffiliate of Codexis) for manufacture of Catalysis Products, or          (b) any Catalysis Product or Fermentation Product for sale to a Third Party (other thanan Affiliate of Codexis) for further processing or formulation, or
 

 
          (c) any Catalysis Product or Fermentation Product that will be formulated by Codexisfor sale to a Third Party, which Product contains one or more Functional Compounds approvedby a Regulatory Authority for human or veterinary pharmaceutical use, where such FunctionalCompound(s) (i) is (are) no longer covered by issued patents in the country where suchproduction will occur, or (ii) is (are) covered by issued patents owned or Controlled by aThird Party (other than an Affiliate of Codexis) that has contracted to have Codexisformulate such Product on behalf of such Third Party, or          (d) any Scheduled Product for sale to a Third Party (other than an Affiliate ofCodexis) for further processing or formulation, or          (e) any Supplemental Product for sale to a Third Party (other than an Affiliate ofCodexis) for further processing or formulation.3. Section 1.12 is amended to provide in its entirety, as follows:     1.12 **“Codexis Field”**shall mean:          (a) Biocatalyst Commercialization and Enzyme Commercialization, subject to thelimitations set forth in Section 2.2.2 and the rights of MUS and Third Parties described inSection 2.8;          (b) Building Block Development;          (c) Bulk Production of Products (except Supplemental Products), subject to thelimitations set forth in Section 2.2.2 and the rights of MUS and Third Parties described inSection 2.8;          (d) Bulk Production of Supplemental Products to which Codexis has acquired rightspursuant to Sections 2.1.6(c) or (d), subject to the limitations set forth in Section 2.2.2and the rights of MUS and Third Parties described in Section 2.8.4. Section 1.17 is amended to provide in its entirety, as follows:          1.17 **“Enabling Technology”**shall mean all Patent Applications and Patents Controlled byMUS that claim (i) methods of generating genetic diversity (including, without limitation,DNA Shuffling with tangible materials or insilico), or the use thereof,and/or (ii) generally applicable screening techniques, methodologies or processes foridentifying genetic variants of interest that: (a) are filed on or before the SeparationEvent, or (b) claim inventions conceived and reduced to practice or otherwise developed onor before the Separation Event, which Patent Application or Patent is filed on or before thethird anniversary of the Separation Event. Enabling Technology shall include MUS’ interestin Third Party Improvements, if any. A list of Patent Applications and Patents within theEnabling Technology existing as of the Effective Date is attached as **Exhibit B**hereto
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5. Section 1.40 is amended to provide in its entirety, as follows:     1.40 **“Product”**shall mean any Catalysis Product, Enzyme Product, Scheduled Product,Supplemental Product, Biocatalyst or Fermentation Product that:          (a) is made or developed with the use of Enabling Technology, whether by GeneExpression Manipulation and/or Metabolic Pathway Manipulation and/or Strain Improvement orotherwise (e.g., incorporates any variant gene made with Enabling Technology, and/or anyprotein or peptide expressed therefrom), and/or          (b) is developed with the use of Product Technology, or incorporates, or is made using,or is substantially derived from, Product Technology.6. Section 1.41 is amended to provide in its entirety, as follows:     1.41 **“Product Technology”**shall mean the Patent Applications and Patents Controlled byMUS on or before the Separation Event that are necessary or useful for use in the CodexisField, that are not included in Enabling Technology or the Assigned Patents. A list of thePatent Applications and Patents within the Product Technology existing as of the EffectiveDate is attached as **Exhibit D**hereto.7. Section 2.1.1 is amended to read in its entirety as follows:     2.1.1 Licenses. Subject to the terms and conditions herein, including withoutlimitation Sections 2.2, 2.4, 2.6, 2.7 and 2.8, MUS hereby grants to Codexis, and Codexishereby accepts, irrevocable (except as provided in Sections 9.4.1, 12.2, 12.3 and 12.4),worldwide, royalty-free (subject to Section 2.1.5(b)) licenses, as follows:          (a) with respect to the Enabling Technology and related Know-How:               (i) an exclusive license in Microbes to develop, make, have made, use, import, haveimported, offer for sale, sell or otherwise commercialize or distribute Products (includingthose Supplemental Products that Codexis has acquired rights to pursuant to Section 2.1.6(c), but excluding, until the Reserved SubField Termination Date, other SupplementalProducts) and corresponding Services in the Codexis Field; and               (ii) a non-exclusive license in Category II Plants to develop, make, have made, use,import, have imported, offer for sale, sell or otherwise commercialize or distributeProducts (including those Supplemental Products that Codexis has acquired rights to pursuantto Section 2.1.6 (c), but excluding, until the Reserved SubField Termination Date, otherSupplemental Products) and corresponding Services in the Codexis Field; and          (b) subject to the terms of Section 2.1.6(a), with respect to the Enabling Technologyand related Know-How, in the period from the Amendment Date until the Reserved SubFieldTermination Date:
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               (i) an exclusive license in Microbes to develop, make, have made, use, import, haveimported, offer for sale, sell or otherwise commercialize or distribute SupplementalProducts and corresponding Services; and               (ii) a non-exclusive license in Category II Plants to develop, make, have made, use,import, have imported, offer for sale, sell or otherwise commercialize or distributeSupplemental Products and corresponding Services; and          (c) with respect to the Enabling Technology and related Know-How, a non-exclusivelicense to develop, make and use Expression Hosts for Internal Research Use; and          (d) with respect to the Product Technology and related Know-How:               (i) an exclusive license in Microbes to develop, make, have made, use, import, haveimported, offer for sale, sell or otherwise commercialize or distribute Products (includingthose Supplemental Products that Codexis has acquired rights to pursuant to Section 2.1.6(c), but excluding, until the Reserved SubField Termination Date, other SupplementalProducts) and corresponding Services in the Codexis Field; and               (ii) a non-exclusive license in Category II Plants to develop, make, have made, use,import, have imported, offer for sale, sell or otherwise commercialize or distributeProducts (including those Supplemental Products that Codexis has acquired rights to pursuantto Section 2.1.6 (c), but excluding, until the Reserved SubField Termination Date, otherSupplemental Products) and corresponding Services in the Codexis Field; and          (e) subject to the terms of Section 2.1.6(a), with respect to the Product Technologyand related Know-How, in the period from the Amendment Date until the Reserved SubFieldTermination Date:               (i) an exclusive license in Microbes to develop, make, have made, use, import, haveimported, offer for sale, sell or otherwise commercialize or distribute SupplementalProducts and corresponding Services; and               (ii) a non-exclusive license in Category II Plants to develop, make, have made, use,import, have imported, offer for sale, sell or otherwise commercialize or distributeSupplemental Products and corresponding Services.8. Article 2.1 is revised by the addition of new Sections 2.1.6 and 2.1.7:          2.1.6 Reserved SubField. With regard to the Reserved SubFields set forth onExhibit G:               (a) Until the Reserved SubField Termination Date, Codexis may practice licenses asdescribed in Sections 2.1.1(b) and (e), on a Category-by-Category basis, if for suchCategory Codexis:
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                    (i) enters into a written contract (including any government grant) with a Third Partythat will provide Codexis with at least **[****]**over a continuous period of **[****]**months orless from such Third Party to (a) conduct research using the Enabling Technology in theapplicable Category, or (b) develop for commercial uses Products subject to Section 1.40(a)in the applicable Category; or                    (ii) expends its own funds, in an amount of at least **[****]**over a continuous periodof **[****]**months or less, to (a) conduct research using Enabling Technology in theapplicable Category, or (b) develop for commercial uses Products subject to Section 1.40(a)in the applicable Category; or                    (iii) expends its own funds and funds from a Third Party collaborator, which fundstotal at least **[****]**over a continuous period of **[****]** months or less, to conduct (a)research using Enabling Technology in the applicable Category, or (b) develop for commercialuses one or more Products in the applicable Category.The Codexis Board of Directors (with appropriate recusals for interested party transactions)must approve the transactions and/or Codexis expenditures described in this Section2.1.6(a).               (b) Commencing on the first anniversary of the Amendment Date and annually thereafteron the anniversary of the Amendment Date until the Reserved SubField Termination Date, andat Codexis’ option, at other times, Codexis shall provide MUS with a written report (i)identifying all Supplemental Products and Categories with regard to which Codexis hasconducted research subject to Section 2.1.6(a) above, and (ii) reporting, by Category, theamount of funds expended by Codexis to conduct research in each such Category in thepreceding twelve (12) month period.               (c) If Codexis has conducted activities subject to Section 2.1.6(a) as to a particularCategory, Codexis shall notify MUS in writing (the “Category Notice”) providing a detailedexplanation of why it believes the Section 2.1.6(a) criteria have been fulfilled with regardto the applicable Category. Within thirty (30) days following the date of such CategoryNotice, senior business representatives of MUS and Codexis shall jointly prepare and sign awritten summary (the “Category Summary”) identifying the Category and correspondingSupplemental Product(s) subject to Section 1.59(a). All Supplemental Products in suchagreed Category Summary shall be included in the Codexis Field (subject to the applicableSubField exclusions set forth on Exhibit G) for all purposes of this Agreement, as of thedate of the applicable agreed Category Summary. Any dispute regarding the subject matterthat will be added to the Codexis Field pursuant to this Section 2.1.6(c) shall be resolvedas set forth in Article 13.               (d) If Codexis has conducted activities that meet the criteria set forth in Section2.1.6(a) above with regard to at least one-half of the Categories of any * Certain information on this page has been omitted and filedseparately with the Securities and Exchange Commission. Confidential treatmenthas been requested with respect to the omitted portions.
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SubField, then, from and after the date of such occurrence (the “Subfield InclusionDate”), such entire SubField (including all its Categories) shall, subject to the applicableSubField exclusions set forth on Exhibit G, thereafter be included in the Codexis Field forall purposes of this Agreement. Within thirty (30) days following the SubField InclusionDate, senior business representatives of MUS and Codexis shall jointly prepare a writtensummary identifying (i) those Supplemental Product(s) subject to Section 1.59(a) withinCategories that have not become part of the Codexis Field, and (ii) those Categories andSubFields have become included in the Codexis Field. Any dispute regarding the subjectmatter that will be added to the Codexis Field shall be resolved as set forth in Article 13.               (e) After the Reserved SubField Termination Date, Codexis shall retain the right tocomplete research regarding a particular Supplemental Product that it commenced prior tosuch date pursuant to Section 2.1.6(a) if it has expended at least **[****]**on such researchwith respect to such Supplemental Product by the Reserved SubField Termination Date, and tocommercialize Supplemental Products resulting from such activities, but otherwise Codexisshall not have any other rights with regard to any Category(ies) or SubField(s) that are notwithin the Codexis Field after the Reserved SubField Termination Date.               (f) Until the date that Codexis acquires license rights under this Agreement to aparticular Supplemental Product pursuant to Sections 2.1.6 (c) or (d), Codexis may not grantany Third Party (i) a sublicense to the Enabling Technology for the development ormanufacture of any Supplemental Product, or (ii) an option to (1) obtain a sublicense to theEnabling Technology for use with regard to the development or manufacture of anySupplemental Product, or (2) use the Enabling Technology to develop or manufacture anySupplemental Product. It is understood and agreed that Codexis may grant such sublicensesand options to Supplemental Products which have become included in the Codexis Fieldpursuant to Section 2.1.6(c) above as a result of Codexis having satisfied the conditions of2.1.6(a).               (g) Until the Reserved SubField Termination Date, MUS will not (i) itself use theEnabling Technology to develop or manufacture any Supplemental Product, or (ii) grant aThird Party a license to use the Enabling Technology to develop or manufacture anySupplemental Product.               (h) It is understood and agreed that as of the Reserved SubField Termination Date, theReserved SubFields (including each Category and SubField) shall be terminated and shall haveno content or force or effect for the remainder of the term of the Agreement.          2.1.7 Rights to Negotiate for Rights Outside the Codexis Field. * Certain information on this page has been omitted and filedseparately with the Securities and Exchange Commission. Confidential treatmenthas been requested with respect to the omitted portions.
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               (a) Codexis Proposal. If Codexis wishes to use the Enabling Technology outsidethe then-current scope of the Codexis Field to make a particular commodity chemical or finechemical, then Codexis shall have a right of negotiation to obtain from MUS a license to usethe Enabling Technology to make such specific products via processes proposed by Codexis.In any such event, Codexis shall notify MUS in writing of the particular processes andspecific commodity chemical(s) or fine chemical(s). If Codexis notifies MUS that Codexiswishes to negotiate for an expanded license to the Enabling Technology as described in thisSection 2.1.7(a), Codexis and MUS shall for a period of one hundred twenty (120) days fromCodexis’ notice, or such longer period as the parties may agree in writing, negotiate termsand conditions for such license rights.               (b) MUS Notice. If MUS wishes to use or license a Third Party to use theEnabling Technology to make a particular commodity chemical or fine chemical for industrialmanufacturing applications outside the then-current scope of the Codexis Field, then untilthe Separation Event, MUS shall notify Codexis, and Codexis shall have a first right ofnegotiation to obtain from MUS a license to use the Enabling Technology to make suchspecific products. In any such event, MUS shall notify Codexis in writing of the particularprocesses and specific commodity chemical(s) or fine chemical(s), subject to any obligationsof confidentiality owed to a Third Party. If Codexis notifies MUS in writing within thirty(30) days of notice by MUS pursuant to this Section 2.1.7(b) that Codexis wishes tonegotiate for an expanded license to the Enabling Technology for the applicable processesand products, then for a period of one hundred twenty (120) days from MUS’ notice, or suchlonger period as the parties may agree in writing, MUS and Codexis shall negotiate terms andconditions for such license rights. For the avoidance of doubt, it is understood and agreedthat this Section 2.1.7(b) shall apply only to proposed uses of Enabling Technology formanufacturing of commodity chemicals or fine chemicals for industrial applications, andshall not apply to any other application outside the Codexis Field, including, withoutlimitation, to any proposed use for discovery, research, development or manufacturing ofpharmaceuticals, vaccines or Agrochemicals and/or for any application relating toagriculture, e.g., processing of food or feed.               (c) Agreement on Terms. If the Parties agree upon mutually acceptable termsand conditions pursuant to Section 2.1.7(a) or Section 2.1.7(b), the Parties shall enterinto a written amendment to this Agreement modifying the license granted to Codexis asappropriate to include the relevant rights and applicable chemicals. Neither Party shall beobligated to accept or agree to such terms or conditions, or to enter into any agreementregarding such expanded license rights. If MUS and Codexis do not agree upon mutuallyacceptable terms and conditions within the applicable time period above, Codexis shall haveno right or license to use the Enabling Technology outside the then-existing Codexis Field.9. Section 2.2.2(b)(i) is deleted, such that Section 2.2.2(b) provides in its entirety, asfollows:
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          (b) to make, have made, use, promote, market, distribute and/or sell any products(including, without limitation, any Products) intended for use in the Detection and ResearchReagent Field; or10. Section 2.2.2(c) is revised by the insertion of the word “itself” before the word “develop”. 11. Revise Sections 2.2.2(f)(ii) and 2.2.2(h) by changing each occurrence of “discovery” to“Discovery”, and revise Section 2.8.5 by changing “discover” to “conduct Discovery of”. 12. Section 2.3 is amended to read in its entirety as follows:     2.3 Right to Sublicense. Codexis (or its successor) may grant sublicenses tothe Enabling Technology, Product Technology and related Know-How to such Third Parties as itdeems appropriate, but such sublicenses may only grant rights to practice in the CodexisField; provided, Codexis may not (i) sublicense the rights granted in Section 2.1.1(c)except in connection with a grant of a sublicense of the rights granted it in Section2.1.1(a), or (ii) sublicense the rights granted it in Section 2.1.1(b) or 2.1.1(e). Codexis(or its successor) may grant licenses to the Assigned Patents as it deems appropriate.13. Section 2.7.1 is amended to provide in its entirety as follows:     2.7.1 MUS. Notwithstanding the license grants in Section 2.1, the Partiesagree that:          (a) MUS and its wholly-owned Affiliates shall, until the Separation Event, retain theright to conduct research with the Enabling Technology and related Know-How in the CodexisField and/or the Reserved SubFields for the purpose of (i) improving and expanding EnablingTechnology, and/or (ii) exploring applications of the Enabling Technology for areas outsidethe Codexis Field and/or the Reserved SubFields; provided, MUS and its wholly-ownedAffiliates shall not use the Enabling Technology for the primary intended purpose ofdeveloping any Products or Services for use in the Codexis Field and/or the ReservedSubFields, on its own behalf or on behalf of any Third Party.          (b) At all times during and after this Agreement, nothing herein shall restrict, or beconstrued to restrict, MUS’ right to practice and grant licenses to practice the EnablingTechnology and Product Technology and/or use related Know-How, outside the Codexis Fieldand/or the Reserved SubFields.          (c) It is understood and agreed that, at all times, MUS shall retain (i) the right(sublicensable to its Affiliates) to internally use the Enabling Technology, ProductTechnology and related Know-How to conduct Discovery and development of pharmaceuticaland/or Agrochemical products by any means (which may include, without limitation, thedevelopment of Building Blocks, the addition of Building Blocks to Templates and/oranaloging of Functional Compounds), and to conduct
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commercialization of such products; and(ii) the sublicensable right to make and/or have made, use, import, have imported, offer forsale and/or sell any such products.14. Section 2.7.2 is revised to provide in its entirety as follows:     2.7.2 Codexis. Except as expressly set forth in this Agreement, nothing hereinshall limit the ability of Codexis to use any intellectual property, tangible property ortechnology not subject to this Agreement, whether the foregoing is developed by it oracquired by it (by license, acquisition or otherwise) for any purpose, in or outside theCodexis Field.15. Section 3.2 is amended to provide in its entirety, as follows:     3.2 License to MUS. In partial consideration for the rights granted herein,Codexis shall grant and hereby grants, and MUS hereby accepts, the following licenses:          (a) with respect to Patent Applications and Patents within the scope of Section 1.4(a),an exclusive, worldwide, royalty-free, irrevocable license, with the right to grant andauthorize sublicenses; and          (b) with respect to Patent Applications and Patents within the scope of Section 1.4(b),subject to the terms of the applicable Third Party Agreement as described in Section 3.3.1,an exclusive (to the extent permitted by the applicable Third Party Agreement), worldwide(to the extent permitted by the applicable Third Party Agreement), royalty-free (subject toSection 3.3.2), irrevocable (to the extent permitted by the applicable Third PartyAgreement) license, with the right to grant and authorize sublicenses,     in each case, to develop, make, have made, use, import, have imported, offer for sale,sell or otherwise commercialize or distribute Products and Services solely outside theCodexis Field, and until the Reserved Termination Date, the Reserved SubFields.16. Article 4 is amended to read in its entirety as follows:**4. COVENANTS**     4.1 Use Within the Codexis Field. Codexis covenants that it will not knowinglypractice its licenses to the Enabling Technology and related Know-How, or its licenses tothe Product Technology and related Know-How, for the purpose of developing orcommercializing Products or Services for use outside the Codexis Field and/or the ReservedSubField. Codexis further covenants that it will not knowingly make or permit any of itsSublicensees or contractors to knowingly make any release into the environment of anyMicrobe or any Plant which has been modified with the use of Enabling Technology (e.g.,outside a container or containment vessel which precludes exit of any such Microbes orPlants from such container or vessel), without the prior written consent of MUS.     4.2 Use Outside the Codexis Field. MUS covenants that it will not knowinglyuse its retained rights with regard to the Enabling Technology or the Product Technology,
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orknowingly practice its license to Codexis Improvements (if any), for the purpose ofdeveloping or commercializing Products or Services for use in the Codexis Field and/or theReserved SubField; provided that such covenants shall be subject to Section 2.7.1 andfurther provided that such covenants shall terminate with regard to any Patent Applicationsand/or Patents for which Codexis’ license terminates pursuant to Sections 9.2.3(b), 12.2,12.3 and/or 12.4 below.17. Section 9.2.1 is amended to provide in its entirety, as follows:          9.2.1 Patent Prosecution.                    (a) With regard to Patent Applications and Patents within the Product Technology ownedby a Third Party, such Third Party shall have the sole right and discretion to conductPatent Prosecution of such Patent Applications and Patents.                    (b) With regard to Patent Applications and Patents within the Product Technology ownedby MUS, MUS shall have the initial right, but not the obligation, to conduct PatentProsecution of such Patent Applications and Patents, unless such Patent Applications andPatents claim only methods and/or compositions that have substantial, commercially valuableapplications solely within the Codexis Field and/or the Reserved SubFields, in which caseCodexis shall have the right, but not the obligation, to conduct Patent Prosecution of suchPatent Applications and Patents.18. Section 9.2.2 is amended to provide in its entirety, as follows:          9.2.2 Sharing of Prosecution Costs. Codexis shall be responsible forProsecution Costs in connection with Patent Prosecution activities described in Section9.2.1, as follows:                    (a) With regard to Patent Applications and Patents within the Product Technology ownedby a Third Party, the Third Party and Codexis shall agree on the amounts to be paid byCodexis to the Third Party with regard to the Patent Prosecution of such Patent Applicationand/or Patent. Unless otherwise agreed in writing, Codexis agrees it shall pay a pro ratashare of such Prosecution Costs based on the following formula: Codexis’ percentage shareof such Prosecution Costs = 100 (1/1+X), where X equals the number of sublicenses granted byMUS with regard to the applicable Patent Application and/or Patent.               (b) With regard to any Patent Applications and Patents within the Product Technologythat are owned by MUS, if MUS conducts the Patent Prosecution activities described inSection 9.2.1(b), Codexis shall pay to MUS a pro rata share of such Prosecution Costs basedon the number of sublicenses granted by MUS with regard to the applicable Patent Applicationand/or Patent.               (c) With regard to any Patent Applications and Patents within the Product Technologythat are owned by MUS, if Codexis conducts the Patent Prosecution activities described inSection 9.2.1(b), Codexis shall pay one hundred
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percent (100%) of the Prosecution Costsincurred after the Effective Date in connection with such activities.               (d) Any amounts for Prosecution Costs subject to this Section 9.2.2 for which Codexisis responsible will be paid by Codexis to the applicable Third Party (or its designee) or toMUS (or its designee), as applicable, within forty-five (45) days of an invoice therefor.19. Section 9.2 is amended by the addition of new Section 9.2.5:          9.2.5 Opt Out. Notwithstanding Sections 9.2.1 through 9.2.4 above, if Codexisdoes not wish to retain rights to any Patent Application or Patent within the ProductTechnology, Codexis may, with sixty (60) days written notice to MUS, relinquish its licenserights to such Patent Application and Patent. In such event, Codexis shall have no furtherlicense rights under this Agreement with regard to the applicable Patent Applications and/orPatents, (i) shall not be entitled to participate in further Patent Prosecution as describedin Section 9.2.2 with respect thereto, and/or further consultation and/or information rightsas described in Section 9.2.4, with regard to such Patent Applications and/or Patents, (ii)shall have no obligation to pay Prosecution Costs incurred after the effective date oftermination with respect to the applicable Patent Application and/or Patent; (iii) shallhave no further enforcement rights described in Section 10.3 with respect to such PatentApplication and/or Patent. Codexis shall remain obligated to pay its share of any PatentProsecution expenses incurred prior to the applicable effective date of termination.20. Section 10.3 is amended to provide in its entirety, as follows:     10.3 Product Technology.          10.3.1 Infringement in the Codexis Field.               (a) With regard to any Patent within the Product Technology that is owned by a ThirdParty, such Third Party shall have the first right, but not the obligation to enforce suchPatent within the Product Technology against any infringements by Third Parties in theCodexis Field and/or the Reserved SubFields and defend any declaratory judgment action.               (b) With regard to any Patent within the Product Technology that is owned by MUS:                    (i) So long as Codexis retains an exclusive license to the applicable Patent within theProduct Technology and such Patent has applications only in the Codexis Field, Codexis shallhave the first right, but not the obligation, to enforce Patents within the ProductTechnology against any infringements by Third Parties in the Codexis Field and defend anydeclaratory judgment action. If Codexis fails to initiate a suit to enforce such patent inany jurisdiction against a commercially significant infringement in the Codexis within one(1) year of a request by MUS to do so,
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MUS may initiate suit against such infringement, atits expense. In such event, Codexis agrees to join in such action, if required byapplicable law.                    (ii) If Codexis does not have an exclusive license to the applicable Patent and/or ifsuch Patent claims inventions having one or more applications outside the Codexis Field,then MUS shall have the first right, but not the obligation, to enforce such Patent againstany infringements by Third Parties in the Codexis Field and defend any declaratory judgmentaction with respect thereto. If MUS fails to initiate a suit to enforce such Patent in anyjurisdiction against a commercially significant infringement in the MUS Field within one (1)year of a request by Codexis to do so, Codexis may initiate suit against such infringement,at its expense. In such event, MUS agrees to join in such action, if required by applicablelaw.               (c) Notwithstanding Section 10.3.1(b) above, Codexis acknowledges that (i) certainpatents within the Product Technology are and will be owned by Third Parties and, that insome cases, such Third Parties may have retained or may retain the first right, or the soleright to enforce such patents, and (ii) prior to the Effective Date, MUS has granted toThird Parties rights to conduct or participate in the enforcement and/or defense of certainPatent Applications and/or Patents within the Product Technology that are owned by MUS.          10.3.2 Infringement Outside the Codexis Field.               (a) With regard to any Patent within the Product Technology that is owned by a ThirdParty, such Third Party shall have the first right, but not the obligation, at its soleexpense, to enforce such Patents against any infringements by Third Parties outside theCodexis Field and/or the Reserved SubFields and defend any declaratory judgment actionrelating thereto.               (b) With regard to any Patent within the Product Technology that is owned by MUS, MUS(or its designee) shall have the right, but not the obligation, to pursue infringement ofsuch Patents outside the Codexis Field and the Reserved SubFields, but shall consult withCodexis before commencing any such suit.          10.3.3 Recoveries. Any recovery received by a Party hereto as a result of anyclaim, suit or proceeding brought pursuant to this Section 10.3 shall be used first toreimburse the Party(ies), and any involved Third Party, for all expenses (includingattorneys and professional fees) incurred in connection with such claim, suit or proceeding.Any amounts recovered by a Third Party in a claim, suit or proceeding pursued solely bysuch Third Party may be retained by such Third Party. With regard to any other recovery,after reimbursement as described in the preceding sentence, the remainder shall be dividedas follows: (a) in any suit relating primarily to infringement in the Codexis Field and/orthe Reserved SubFields, seventy percent (70%) to the Party initiating the suit, and thirtypercent (30%) to the other Party, and (b) in any suit primarily relating to infringementoutside the Codexis Field and/or the Reserved SubFields, as MUS determines or as may beagreed by the Parties in writing.21. Section 10.7.3 is revised to read in its entirety, as follows:
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     10.7.3 Codexis Responsibility. If any claim, suit or proceeding subject tothis Section 10.7 is based on allegations relating to the conduct or activities of Codexisand/or its Sublicensees, unless such claim, suit or proceeding is based solely on anallegation that the practice of the Enabling Technology infringed a patent owned by a ThirdParty, then Codexis shall have the right and responsibility to conduct the defense of suchaction, and shall pay the costs of defense of any such action.22. Revise Sections 1.31 such that the phrase “within the Codexis Field’ shall be amended to read“within the Codexis Field, and until the Reserved SubField Termination Date, the ReservedSubFields”. 23. Revise Sections 1.32, 1.33, 1.41, 1.53, 2.2.1 and 7.1.3 by adding the phrase “and/or theReserved SubFields” after each occurrence of the phrase “in the Codexis Field”. 24. Revise Sections 2.2.2(f), 2.2.3, 2.5, 2.7.2, 2.8.2, 4.1, 8.1 and 9.2.1 by adding the phrase“and/or the Reserved SubFields” after each occurrence of the phrase “outside the CodexisField”. 25. Exhibits F and G attached to this Amendment No. 1 shall become exhibits to the Agreement. 26. Except as expressly provided herein, the terms of the Agreement shall remain in full forceand effect.[THE REMAINDER OF THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK]
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     IN WITNESS WHEREOF, MUS and Codexis have executed this Amendment No. 1 to License Agreement asof the first above written.           MAXYGEN, INC.   CODEXIS, INC.             By: /s/ Russell J. Howard   By: /s/ Alan Shaw  Name:  Russell J. Howard   Name:  Alan Shaw  Title: Chief Executive Officer   Title: President  
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**Exhibit F****Scheduled Products**1. Products for the following petrochemical applications:Crude Oil Applicationsenhancement of recovery of down-hole crude