**Exhibit10.18 (b)Execution Version**

**AMENDED AND RESTATED**

**LICENSE AGREEMENT**

This AMENDED AND RESTATED LICENSE AGREEMENT (this “Agreement”),dated effective as of October 27, 2006 (the “Effective Date of thisAgreement”), is entered into by and between XOMA Ireland Limited, a companywith limited liability organized under the laws of the Republic of Irelandhaving offices at Shannon Airport House, Shannon, County Clare, Ireland (withits Affiliates, “XOMA”) and DYAX Corp., a corporation organized underthe laws of the State of Delaware having offices at 300 Technology Square, Cambridge,Massachusetts 02139, U.S.A. (with its Affiliates, “DYAX”).

**BACKGROUND**

A.           XOMA is the owner or exclusive licensee of certain patentrights and know-how relating to bacterial cell expression, and DYAX wishes toacquire non-exclusive licenses under such patent rights and know-how; and

B.            DYAX is the owner or exclusive licensee of certain patentrights relating to phage display technologies (generally known as the Ladnerand related patent rights), and XOMA wishes to acquire non-exclusive licensesunder such patent rights; and

C.            XOMA and DYAX previously executed a License Agreement,dated effective as of October 16, 2002 (the “Effective Date of the OriginalAgreement”), under which (i) XOMA granted to DYAX certain non-exclusivelicenses to engage in certain research, development and commercial activities,and (ii) DYAX granted to XOMA certain non-exclusive licenses to engage incertain research, development and commercial activities (the “OriginalAgreement”); and

D.            XOMA has requested that DYAX provide XOMA with certainquantities of its most recently developed antibody phage display libraries touse in connection with the license granted herein by DYAX to XOMA;  and

E.            DYAX is willing to provide such libraries to XOMA if theterms of the Original Agreement are amended and restated as set forth herein.

NOW, THEREFORE, in consideration of the promises and the mutualcovenants hereinafter recited, the parties agree that, from and after the datehereof, the Original Agreement shall be amended and restated as follows:

**ARTICLE 1.    DEFINITIONS**

In this Agreement, thefollowing terms shall have the meanings set forth in this Article.

**Confidentialmaterials omitted and filed separately with the Securities and ExchangeCommission. An asterisk in brackets [*] denotes such omission.**

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1.1           “Affiliate” means any corporation or other entitywhich is directly or indirectly controlling, controlled by or under commoncontrol with a party hereto. For purposes of this Agreement, “control”(including, with correlative meanings, the terms “controlled” and “controlling”)means the possession, directly or indirectly, of the power to direct or causethe direction of the management or policies of the subject corporation or otherentity, whether through the ownership of voting securities, by agreement or otherwise.

1.2            “Antibody Phage Display” means the authorized useof Licensed Antibody Phage Display Materials to conduct Research andDevelopment.

1.3            “Change in Control” means, with respect to DyaxCorp. or XOMA Ltd., any transaction or series of transactions as a result ofwhich any person or group (as defined under the U.S. Securities Exchange Act of1934, as amended) becomes, directly or indirectly, the beneficial owner of morethan fifty percent (50%) of the total voting power of such entity’s equitysecurities or otherwise gains control of such entity.

1.4            “Commercial Antibody Phage Display Business”means, with respect to immunoglobulin or antibody phage display services,immunoglobulin or antibody phage display libraries, immunoglobulin or antibodyphage display products or immunoglobulin or antibody phage display materials,the out-licensing, commercial manufacture, sale, offer for sale, import forsale or export for sale of such immunoglobulin or antibody phage displayservices, libraries, products and materials.

1.5            “Confidential Information” means any proprietaryor confidential information or material disclosed by a party to the other partypursuant to this Agreement, which is (i) disclosed in tangible form hereunderand is designated thereon as “Confidential” at the time it is delivered to thereceiving party, or (ii) disclosed orally hereunder and identified asconfidential or proprietary when disclosed and such disclosure of confidentialinformation is confirmed in writing within thirty (30) days by the disclosingparty.

1.6            “Development Partner” means a Third Party fromwhom a party either in- licenses a target for development and/orcommercialization by the in-licensing party or with whom a party shares theeconomic risk of development or commercialization of a target or product beingdeveloped or commercialized on behalf of the applicable party.

1.7            “Dispose” means to transfer, assign, lease, or inany other fashion dispose of control, ownership or possession, but shall notmean to license or sell. “Disposition” shall have the correlativemeaning.

1.8            “DYAX Collaborator” means any person or entity whois an authorized end-user of Licensed Antibody Phage Display Materials, theintended recipient of Licensed Immunoglobulins or Licensed ImmunoglobulinInformation transferred from DYAX and/or a person or entity on whose behalfDYAX knowingly engages in Antibody Phage Display. Except as expressly set forthon Schedule 2.9(i). no person or entity shall be deemed to be a DYAXCollaborator if such person or entity is engaged in a Commercial Antibody PhageDisplay Business unless, pursuant to a written agreement (other than this 

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Agreement), executed afterthe Effective Date of the Original Agreement, XOMA has granted to such personor entity a valid license or covenant not to sue under the XOMA Patent Rightswhich explicitly extends to the activities identified in this third to lastsentence of Section 1.8. XOMA shall provide DYAX prompt written notice of thosewritten agreements or covenants not to sue which satisfy the requirements ofthe prior sentence. No person or entity may claim the status of DYAXCollaborator with respect to any acts or activities which are unrelated to theuse of Licensed Antibody Phage Display Materials provided by DYAX.

1.9           “DYAX Patent Rights” means the patent applicationsand patents listed on Schedule 1.9 hereto and, solely to the extent anyValid Claim would cover or be included in the license grants provided forherein, all divisions, continuations, continuations-in-part, applicationsclaiming priority thereto, and substitutions thereof; all foreign patentapplications corresponding to the preceding applications; all U.S. and foreignpatents issuing on any of the preceding applications, including extensions,reissues and re-examinations; and any other patent rights owned or licensed byDYAX, whether now existing or obtained in the future, which DYAX has the rightto license or sublicense and which would be infringed by the activities of XOMAcontemplated hereunder but for this Agreement. DYAX Patent Rights shall also include(i) any improvements of the foregoing that are owned or controlled by DYAX and(ii) any patents or patent applications, whether now existing or obtained inthe future, owned or controlled by DYAX containing a claim that is dominatingover the foregoing patent rights (i.e., is necessarily infringed by thepracticing of a claim in one of the foregoing applications).

1.10         “First Commercial Sale” means the initial transfer byDYAX (either directly or through a Third Party, including without limitationany joint venture or similar arrangement in which DYAX and/or a DevelopmentPartner of DYAX is a participant) of a Product for value and not fordemonstration, testing or promotional purposes.

1.11         “Immunoglobulin” means any molecule, includingwithout limitation, full immunoglobulin molecules (e.g., IgG, IgM, IgE, IgA andIgD molecules) and ScFv, Fv and Fab molecules, that has an amino acid sequenceby virtue of which it specifically interacts with an antigen and wherein thatamino acid sequence consists essentially of a functionally operating region ofan antibody variable region including, without limitation, any naturallyoccurring or recombinant form of such a molecule.

1.12         “Licensed Antibody Phage Display Materials” means (i)any collection or library of polynucleotide sequences, created by and under theexclusive control of DYAX, which encodes at least one Immunoglobulin and whichis contained in filamentous bacteriophage and/or bacteriophage or phagemidcloning vectors capable of propagation in bacteria; or (ii) any collection or libraryof bacteriophage, created by or under the exclusive control of DYAX, wherein anImmunoglobulin is expressed as a fusion protein comprising an Immunoglobulin orat least a functionally operating region of an antibody variable region and anouter surface polypeptide of a bacteriophage. For the avoidance of doubt, andwithout expanding the definition thereof, specifically excluded from thedefinition of Licensed Antibody Phage Display Materials are (x) any article ofmanufacture or composition of matter suitable for display, expression orsecretion of an Immunoglobulin in or from any organism or system other thanbacteria and (y) any materials or composition of matter otherwise meeting thedefinition of Licensed Antibody Phage

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Display Materials but createdby or under the control of any entity, other than DYAX, engaged in a CommercialAntibody Phage Display Business; *provided,*that,notwithstanding the foregoing, any materials or composition of matter otherwisemeeting the definition of Licensed Antibody Phage Display Materials but createdby or under the exclusive control of a DYAX Collaborator shall constituteLicensed Antibody Phage Display Materials, but only to the extent derived bysuch DYAX Collaborator exclusively from Licensed Antibody Phage DisplayMaterials created by or under the exclusive control of DYAX and properlytransferred by DYAX to such DYAX Collaborator in accordance with the applicableprovisions of this Agreement and such DYAX Collaborator acknowledges that thetransfer restrictions and other provisions hereof apply thereto.

1.13          “Licensed Immunoglobulin” means any Immunoglobulindiscovered, isolated or characterized by DYAX or a DYAX Collaborator (asdefined above) through the use of Licensed Antibody Phage Display Materials.

1.14          “Licensed Immunoglobulin Information” means anydata, know-how or other information relating, concerning or pertaining to aLicensed Immunoglobulin, including, without limitation, data, know-how or otherinformation characterizing or constituting such Licensed Immunoglobulin’s polynucleotideor amino acid sequence, purported function or utility, antigen bindingaffinity, or physical or biochemical property.

1.15          “Net Sales” means, solely with respect to sales byDYAX (either directly or through a Third Party, including without limitationany joint venture or similar arrangement in which DYAX and/or a DevelopmentPartner of DYAX is a participant), the gross amount invoiced by DYAX (or suchjoint venture or similar arrangement) to an independent Third Party less thefollowing items:

(a)                                  Trade, cash and quantity discounts actuallyallowed and taken directly with respect to such sales;

(b)                                 Excises, sales taxes or other taxes imposedupon and paid directly with respect to such sales (excluding national, state orlocal taxes based income);

(c)                                  Amounts repaid or credited by reason ofrejections, defects, recalls or returns or because of rebates or retroactiveprice reduction; and

(d)                                 Freight, transportation and insurance.

Net Sales shall not include any considerationreceived by DYAX (or any such joint venture or similar arrangement) in respectof the sale, use or other disposition of such Product in a country as part of aclinical trial prior to the receipt of all regulatory approvals required tocommerce full commercial sales of such Product in such country, except salesunder “treatment INDs,” “named patient sales,” “compassionate use sales,” ortheir equivalents pursuant to which DYAX (or any such joint venture or similararrangement) is entitled, under applicable laws, regulations and regulatorypolicies, to recover costs incurred in providing such Product to patients.

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1.16         “Product” means any composition of matter or articleof manufacture, including without limitation any diagnostic, prophylactic ortherapeutic product, which (a) contains a Licensed Immunoglobulin; or (b) wasdiscovered or created by, arose out of or is related to use of LicensedAntibody Phage Display Materials or the conduct of Antibody Phage Display byDYAX or a DYAX Collaborator; or (c) is sold by or on behalf of DYAX or a DYAXCollaborator under conditions which, if unlicensed, would constituteinfringement of the XOMA Patent Rights.

1.17         “Research and Development” means the identification,selection, isolation, purification, characterization, study and/or testing ofan Immunoglobulin for any purpose, including, without limitation, anyactivities relating to the discovery and development of human therapeutic ordiagnostic products. Included within the definition of “Research andDevelopment” shall be all *in vitro*screeningor assays customarily performed in pre-clinical and clinical research and usesassociated with obtaining FDA or equivalent agency regulatory approval.Notwithstanding anything to the contrary contained herein, “Research and Development”shall not include use of the XOMA Expression Technology in commercial orindustrial manufacture or any activities solely directed to the creation ofsuch capacities.

1.18         “Research Quantities” means those quantities of anImmunoglobulin reasonably required for Research and Development purposes.

1.19         “Third Party” means any person or entity other thanDYAX or XOMA.

1.20         “Valid Claim” means (i) a claim of an issued andunexpired patent included within the DYAX Patent Rights or the XOMA Patent Rights,as the case may be, which has not been held invalid in a final decision of acourt of competent jurisdiction from which no appeal may be taken, and whichhas not been disclaimed or admitted to be invalid or unenforceable throughreissue or otherwise, or (ii) a claim of a pending patent application withinthe DYAX Patent Rights or the XOMA Patent Rights, as the case may be.

1.21         “XOMA Expression Technology” means any method,composition of matter or article of manufacture suitable for the expression of afunctional Immunoglobulin in a prokaryote.

1.22         “XOMA Field of Use” means all fields.

1.23         “XOMA Know-How” means unpatented and/or unpatentabletechnical information, including ideas, concepts, inventions, discoveries,data, designs, formulas, specifications, procedures for experiments and testsand other protocols, results of experimentation and testing, fermentation andpurification techniques, and assay protocols, whether now existing or obtainedin the future, owned by XOMA which XOMA has the right to license or sublicenseand which may be necessary for the practice of the applicable XOMA PatentRights or which would be misappropriated by the activities of DYAX or the DYAXCollaborators contemplated hereunder but for this Agreement. XOMA Know-Howshall not include the XOMA Patent Rights. All XOMA Know-How shall beconfidential information of XOMA.

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1.24         “XOMA Patent Rights” means the patent applicationsand patents listed on Schedule 1.24 hereto and, solely to the extent anyValid Claim would cover or be included in the license grants provided forherein, all divisions, continuations, continuations-in-part, applicationsclaiming priority thereto, and substitutions thereof; all foreign patentapplications corresponding to the preceding applications; all U.S. and foreignpatents issuing on any of the preceding applications, including extensions,reissues and re-examinations; and any other patent rights owned by XOMA whichXOMA has the right to license or sublicense and which would be infringed by theactivities contemplated hereunder but for this Agreement. XOMA Patent Rightsshall also include (i) any improvements of the foregoing that are owned or controlledby XOMA and (ii) any patents or patent applications, whether now existing orobtained in the future, owned or controlled by XOMA containing a claim that isdominating over the foregoing patent rights (i.e., is necessarily infringed bythe practicing of a claim in one of the foregoing applications).

The above definitions areintended to encompass the defined terms in both the singular and plural forms.

**ARTICLE 2.    XOMA GRANT OF RIGHTS TO DYAX**

2.1      License Grants. Subject to theother terms and conditions of this Agreement, XOMA hereby grants to DYAX aworldwide, non-exclusive, non-transferable (other than as provided in Section9.2) license, without any right to sublicense, under the XOMA Patent Rights andthe XOMA Know-How to:

(a)                                  on its own behalf and on behalf of a DYAXDevelopment Partner or DYAX Collaborator, make or have made Licensed Antibody PhageDisplay Materials;

(b)                                 on its own behalf and on behalf of a DYAXCollaborator, transfer Licensed Antibody Phage Display Materials;

(c)                                  on its own behalf and on behalf of a DYAXDevelopment Partner or DYAX Collaborator, conduct Antibody Phage Display toidentify and isolate Licensed Immunoglobulin;

(d)                                 on its own behalf and on behalf of a DYAXDevelopment Partner or DYAX Collaborator, use the XOMA Expression Technology inconnection with the use of Licensed Antibody Phage Display Materials to make orhave made Research Quantities of Licensed Immunoglobulin;

(e)                                  on its own behalf and on behalf of a DYAXDevelopment Partner or DYAX Collaborator, use Licensed Immunoglobulin orLicensed Immunoglobulin Information to research and develop, make, have made,use, offer for sale, sell and have sold, import and have imported Products foruse in the treatment, prophylaxis, diagnosis or monitoring of a human diseasestate or condition; and

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(f)                                    on its own behalf and on behalf of a DYAXDevelopment Partner, to make, have made, use, offer for sale, sell and havesold, import and have imported Products for use in the treatment, prophylaxis,diagnosis or monitoring of a human disease state or condition.

For the sake of clarity, (i)the licenses granted in Section 2.1 are personal to DYAX and are to be used onbehalf of any DYAX Collaborator or Development Partner of DYAX only in respectof or in connection with the activities that such DYAX Collaborator orDevelopment Partner of DYAX is engaged in that are the basis for meeting thedefinition of DYAX Collaborator or Development Partner of DYAX, as the case maybe, and not any other activities, and (ii) without limiting the foregoing, thelicense granted in Section 2.1(f) is not to be used on behalf of any DYAXCollaborator or any other Third Party that is not a Development Partner ofDYAX.

2.2           XOMA Transfer to DYAX. Within thirty (30) days ofthe Effective Date of this Agreement, XOMA shall transfer to DYAX, at areasonable place and time of DYAX’s direction, the materials identified on Schedule2.2.

2.3           Covenant Not To Sue. In partial consideration forthe payments set forth in Sections 4.1 and 4.2, XOMA covenants that it shallnot initiate or permit any Third Party over whom it has control to initiate orassist in any way in the initiation or prosecution of any action asserting aclaim of infringement under the XOMA Patent Rights or misappropriation of theXOMA Know-How against DYAX, any Development Partner of DYAX or any DYAXCollaborator solely to the extent reasonably necessary to permit the authorizeduse of Licensed Antibody Phage Display Materials, Licensed Immunoglobulins or LicensedImmunoglobulin Information for activities or in a manner otherwise permittedunder the provisions of this Agreement. The parties agree that the covenant notto sue provided by this Section 2.3 (i) is a covenant that transfers with anyassignment or sale of, or grant of an exclusive license (with the right toenforce) under, the applicable XOMA Patent Rights by XOMA and (ii) withoutlimiting or expanding the provisions of Section 9.2, shall be binding upon anypermitted successors or assigns of XOMA. XOMA agrees to use commerciallyreasonable efforts to assist DYAX in recording in a form reasonably acceptableto XOMA the covenant not to sue provided by this Section 2.3, as permitted,with the U.S. Patent and Trademark Office. The covenant not to sue provided bythis Section 2.3:

(a)                                  shall not extend to the use of the XOMAExpression Technology to make any amount of a Licensed Immunoglobulin orProduct other than Research Quantities; *provided, however,*thatthis limitation shall not preclude the manufacture, in commercial quantities,of a Licensed Immunoglobulin discovered using the XOMA Expression Technology inaccordance with this Agreement when produced in a production system other thana prokaryote;

(b)                                 is personal to DYAX, such Development Partnerof DYAX and such DYAX Collaborator and cannot be assigned or transferred;

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(c)                                  does not constitute a release or waiver ofpast, present or future infringement of the XOMA Patent Rights ormisappropriation of the XOMA Know-How by DYAX or any Third Party, including,without limitation, any DYAX Collaborator acting outside of the scope of thewritten agreement with DYAX provided for in Section 2.5; and

(d)                                 shall become void and without effect as toany entity or person who claims its benefit but fails to materially dischargeor comply with any term of its written agreement with DYAX provided for inSection 2.5.

2.4           No Implied Rights. Only the rights and licensesgranted pursuant to the express terms of this Agreement shall be of any legalforce or effect. No license or other rights shall be deemed to have beengranted to DYAX, a Development Partner of DYAX or a DYAX Collaborator otherthan as expressly provided for in this Agreement. For the avoidance of doubt,the grants of rights made pursuant to Sections 2.1 and 2.3 do not include, andexpressly exclude, the following:

(a)                                 any right or license under the XOMA PatentRights and the XOMA Know-How to engage in any activities on behalf of or incollaboration with any Third Party, other than a Development Partner of DYAX ora DYAX Collaborator;

(b)                                any right or license under the XOMA Patent Rights and the XOMA Know-Howto use the XOMA Expression Technology to make or have made any amount of aLicensed Immunoglobulin or Product other than Research Quantities*; provided, however,*that DYAX or, asapplicable, a DYAX Collaborator shall be permitted to make or have made anyLicensed Immunoglobulin by any means of its selection other than those whichotherwise infringe a Valid Claim of the XOMA Patent Rights or utilize the XOMAKnow-How; and/or

(c)                                 any right to release any Third Party,including a Development Partner of DYAX or a DYAX Collaborator, from any claimof infringement under the XOMA Patent Rights.

2.5           Transfer Restrictions.

(a)  DYAX shall not undertake any Antibody PhageDisplay activities on behalf of a Third Party or Dispose of Licensed AntibodyPhage Display Materials or the product of the practice of any method within thescope of the XOMA Patents (“Transferred Materials”) to any Third Partyuntil such time as such Third Party has entered into a written agreement withDYAX pursuant to which such Third Party acknowledges and expressly agrees:

(i)                                   that the “first sale” doctrine does not applyto any such Disposition;

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(ii)                                  to further Dispose of Transferred Materialsonly to a Third Party who otherwise meets the definition of a DevelopmentPartner or DYAX Collaborator and who executes a written agreement in which itsundertakes all of the obligations applied to the transferring party, *provided*, *however*, thatthis Section 2.5(a)(ii) shall not apply to the Disposition of any LicensedImmunoglobulin where such Third Party is not a Dyax Development Partner and noroyalty is or will otherwise be due under Section 4.1;

(iii)                               that the covenant not to sue provided bySection 2.3 does not extend use of the XOMA Expression Technology to make anyamount of a Licensed Immunoglobulin or Product other than Research Quantities;

(iv)                              that the covenant not to sue provided bySection 2.3 does not constitute a release or waiver of past, present or futureinfringement of the XOMA Patent Rights or misappropriation of the XOMA Know-Howby such Third Party;

(v)                                 that the covenant not to sue provided bySection 2.3 shall be subject to such Third Party’s compliance with Section 8.4;

(vi)                              that the covenant not to sue provided bySection 2.3 is personal to such Third Party (as a DYAX Collaborator or DYAXDevelopment Partner) and cannot be assigned or transferred;

(vii)                           that the covenant not to sue provided bySection 2.3 shall become void and without effect as to any entity or person whoclaims its benefit but fails to materially discharge or comply with theforegoing provisions; and

(viii)                        that XOMA shall be an intended third partybeneficiary with respect to the foregoing provisions.

(b)           Without expanding or limiting the scope of the licensesand covenants not to sue granted by this Agreement, the provisions of Section2.5(a) requiring a written agreement prior to any Disposition of anyTransferred Materials shall not apply to a transfer of (i) a LicensedImmunoglobulin discovered by Dyax to a Third Party who is not a DyaxDevelopment Partner where the making, selling, offering for sale, importing orexporting of such Licensed Immunoglobulin will occur under conditions whichwill not give rise to any obligation to pay XOMA any royalties under Section4.1, or (ii) a Licensed Immunoglobulin discovered exclusively by Dyax to anyThird Party where such Disposition is made pursuant to a bona fide materialtransfer agreement that confers no commercial rights to such Third Party forthe sole purpose of permitting such Third Party to evaluate the transferredLicensed Immunoglobulin; *provided*, *howeve*r, that upon the execution of any subsequent agreementrelating to such Licensed Immunoglobulin, as applicable, the provisions ofSection 2.5(a) shall be incorporated therein.

2.6           Reports, Records and Audits.

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(a)           Thirty (30) days after the end of each calendar quarter,commencing with the first calendar quarter commencing after the Effective Dateof the Original Agreement, DYAX shall deliver to XOMA a written report whichshall specify the name, address and contact person for each and every DYAXCollaborator and any person or entity receiving Licensed Antibody Phage DisplayMaterials or a Licensed Immunoglobulin. The reports delivered by DYAX to XOMApursuant to this Section 2.6(a) shall be Confidential Information of DYAX.

(b)           Not later thanthirty (30) days after the end of each calendar year, commencing with the firstcalendar year to commence after the Effective Date of the Original Agreement,as and to the extent publicly disclosed by DYAX (whether in press releases,government filings or otherwise), DYAX shall deliver to XOMA written materialspertaining to the current status of activities or compositions of matter as towhich DYAX claims the right of license hereunder.

(c)           DYAX shall maintainrecords fully and properly reflecting those activities to be reported to XOMApursuant to Sections 2.6(a) and (b) (the “Records”), in sufficientdetail and in good scientific manner appropriate for patent, regulatory andmanufacturing purposes for at least three (3) years. Upon the written requestof XOMA and not more than once in each calendar year, DYAX shall permit anindependent consultant appointed by XOMA, at XOMA’s expense, to have accessduring normal business hours to such of the records of DYAX as may bereasonably necessary to verify compliance with the terms of this Agreement, aswell as the accuracy of the reports hereunder. DYAX shall certify anystatements by DYAX personnel as to their accuracy and correctness. Theconsultant shall not be permitted to see or receive any specific informationconcerning targets or antibodies of either DYAX or any of its collaborators andshall disclose to XOMA only the results and conclusions of its review and thespecific details concerning any discrepancies. No other information shall beshared by the consultant without the prior consent of DYAX unless disclosure isrequired by law, regulation or judicial order.

2.7           Ownership; Enforcement. At all times XOMA willretain ownership of the XOMA Patent Rights and may use and commercialize suchXOMA Patent Rights itself or with any Third Party. XOMA retains the right, atits sole discretion, to enforce, maintain and otherwise protect the XOMAKnow-How and the XOMA Patent Rights. In addition to the requirements of Section2.6, DYAX shall give XOMA prompt notice of any infringement of any of the XOMAPatent Rights by a Third Party engaging in a Commercial Antibody Phage DisplayBusiness which comes to DYAX’s attention during the term of this Agreement.DYAX will reasonably cooperate with XOMA with respect to any actions XOMA maychoose to take related to the enforcement, maintenance or protection of theXOMA Patent Rights.

2.8           Oppositions and/or Appeals to Oppositions. DYAXhereby agrees not to enter into any opposition to and/or appeal from anydecision by the patent authorities of any country on the XOMA Patent Rights andshall not assist or otherwise cooperate with another party in any suchopposition or appeal.

2.9          ReleaseFrom Past Infringement. XOMA releases DYAX from any claims, demands, andrights of action arising out of and/or based upon any act or omission committedby DYAX prior to the Effective Date of the Original Agreement, including,without limitation, claims of infringement under

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the XOMA Patent Rights (the “Release”) and XOMA releases thoseThird Parties identified upon Schedule 2.9(i) from any claims, demands,and rights of action arising out of and based upon any infringement of the XOMAPatent Rights (the “Third Party Release”): *provided, however,*that the Release and Third Party Releaseprovided for in this Section 2.9 shall extend only to claims, demands or rightsof action existing as of the Effective Date of the Original Agreement and whicharose solely out of those activities specified in Schedule 2.9(ii).Nothing in this Section 2.9 shall be deemed to be a release of any claim,demand or right of action XOMA may now or in the future have against [*] or anyother entity or person engaged in a Commercial Antibody Phage Display Businessor any of their collaborators (except, in the case of any such collaboratorthat is also a collaborator of DYAX, to the extent such collaborator’s activitieswith DYAX are directly and exclusively within the scope of the Third PartyRelease). The Release and the Third Party Release shall become irrevocable onlyupon receipt by XOMA of payment in full by DYAX of all installments of theamounts set forth in Section 4.1 and shall be revoked in their entirety andnull and void *ab initio,*immediatelyand without further action of the parties, in the event any installment of suchamounts is not received by XOMA on or prior to the fifteenth day followingwritten notice to DYAX from XOMA of DYAX’s breach in the payment of the fullamount of such installment on or prior to the payment date for such installmentas set forth in Section 4.1, regardless of any payment received thereafter.

**ARTICLE 3.   DYAX GRANT OF RIGHTS TO XOMA**

3.1           License Grants. Subject to the other terms andconditions of this Agreement, DYAX hereby grants to XOMA, on its own behalf andon behalf of its Development Partners, a fully paid up, non-exclusive,royalty-free, worldwide license under the DYAX Patent Rights, to discover,isolate, optimize, develop, offer to use, use, offer for sale, sell, make, havemade, export and import Immunoglobulins or products containing or comprising anImmunoglobulin in the XOMA Field of Use, including without limitation the rightto conduct phage display under the DYAX Patent Rights but excluding the conductof phage display as a Commercial Antibody Phage Display Business. XOMA shallnot have the right to sublicense its license rights under the DYAX PatentRights to any Third Party. XOMA may not transfer to any Third Party any phagedisplay library the use of which by XOMA is otherwise licensed hereunder if theuse thereof by such Third Party would infringe a Valid Claim of the DYAX PatentRights. For the avoidance of doubt, nothing herein is intended to prevent XOMAfrom transferring any Immunoglobulin or any product containing or comprising anImmunoglobulin to a Development Partner of XOMA or a Third Party working onbehalf of XOMA or a Development Partner of XOMA to make, have made, use, sell,have sold and import products, *provided*that the use of such Immunoglobulinor product by the Development Partner or Third Party does not infringe a ValidClaim of the DYAX Patent Rights. XOMA is licensed hereby to use phage displaymaterials, including without limitation phage display libraries, received fromany Third Party, free from any contractual obligations or limitations otherwiseapplicable thereto, so long as XOMA otherwise abides by the terms andconditions of this Agreement. Any use of such phage display materials by XOMAshall be governed in all respects by the provisions of this Agreement and notthe provisions of any agreements between DYAX and any Third Party providingphage display materials to XOMA. Furthermore, for the avoidance of doubt,solely within the XOMA Field of Use, DYAX grants to XOMA, consistent with theother terms and conditions of this Agreement, a fully paid-

**Confidentialmaterials omitted and filed separately with the Securities and ExchangeCommission. An asterisk in brackets [*] denotes such omission.**

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up, non-exclusive,royalty-free worldwide right and license to use the DYAX Materials (as definedbelow).

3.2           CovenantNot To Sue. DYAX covenants that it shall not initiate or permit any ThirdParty over whom it has control to initiate or assist in any way in theinitiation or prosecution of any action asserting a claim of infringement underthe DYAX Patent Rights against XOMA or any Development Partner of XOMA ormisappropriation of the DYAX Materials against XOMA solely to the extent suchclaims arise out of (a) use of the DYAX Materials by XOMA as permitted underthe provisions of this Agreement or (b) the discovery, isolation, optimizationor development by XOMA, or the manufacture, use, offer for use, sale, offer forsale, importation and exportation, of any Immunoglobulin or product containingor comprising an Immunoglobulin which were discovered under conditions whichbut for this license would constitute misappropriation or infringement of theDYAX Patent Rights.

3.3           DYAX Transfer to XOMA.

(a)            DYAX has previously transferred to XOMA, under the termsof the Original Agreement, all of the materials, including without limitationthe Licensed Antibody Phage Display Materials, specified on Schedule 3.3of the Original Agreement.  Within thirty(30) days after the Effective Date of this Agreement, DYAX shall transfer toXOMA those additional Licensed Antibody Phage Display Materials specified on Schedule3.3 hereof.  Collectively, theLicensed Antibody Phage Display Materials delivered to XOMA under the OriginalAgreement and those additional Licensed Antibody Phage Display Materialsdelivered hereunder, are referred to herein as the “DYAX Materials.”XOMA will be able to consult with DYAX scientific staff at $2,500/person-day(based on an eight hour day) in the use of the DYAX Materials. The cost of allreasonable travel-related expenses will be fully reimbursed to DYAX by XOMA.The DYAX Materials shall be Confidential Information subject to Article 5.  For the avoidance of doubt, all activities ofXOMA using the DYAX Materials on or after the Effective Date of this Agreementshall be subject to the provisions of this Agreement and not the OriginalAgreement.

(b)      DYAX represents and warrants that theDYAX Materials comprise the Licensed Antibody Phage Display Materials,including the know-how and protocols for using such Licensed Antibody PhageDisplay Materials, that DYAX customarily provides to licensees of antibodyphage display libraries for screening purposes.

3.4           Ownership: Enforcement. At all times DYAX willretain ownership or control of the DYAX Patent Rights and may use andcommercialize such DYAX Patent Rights itself or with any Third Party. DYAXretains the right, at its sole discretion, to enforce, maintain and otherwiseprotect the DYAX Patent Rights. XOMA will reasonably cooperate with DYAX withrespect to any actions DYAX may choose to take related to the enforcement,maintenance or protection of the DYAX Patent Rights.

3.5           Oppositions and/or Appeals to Oppositions. XOMAhereby agrees not to enter into any oppositions to and/or appeal from anydecision by the patent authorities of any country on the DYAX Patent Rights andshall not assist or otherwise cooperate with another party in any suchopposition or appeal.

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**ARTICLE 4.          PAYMENTS**

4.1           Technology Access and Release Fee. In considerationfor the rights granted to DYAX and DYAX Collaborators pursuant to Sections 2.1,2.2, 2.3 and 2.9, DYAX has previously paid to XOMA, under the terms of theOriginal Agreement, a fee of Three Million Five Hundred Thousand United StatesDollars (US$3,500,000). XOMA hereby acknowledges receipt of such amount. To theextent that DYAX requires any further assistance in connection with thetransfer of XOMA Expression Technology hereunder, DYAX will be able to consultwith XOMA scientific staff at $2,500/person-day (based on an eight hour day).The cost of all reasonable travel-related expenses will be fully reimbursed toXOMA by DYAX.

4.2           Royalties.

(a)           During the term of this Agreement, DYAX shall pay to XOMA aroyalty in cash equal to [*] percent ([*]%) of the Net Sales of any Product(s)in each calendar quarter, commencing with the first calendar quarter endingafter the Effective Date of the Original Agreement. Notwithstanding the foregoing,no royalty shall be payable on Net Sales by or on behalf of a DYAX Collaboratorthat is not a Development Partner of DYAX where neither DYAX nor anyDevelopment Partner of DYAX directly or indirectly sells the Product.

(b)           Royalties due underthis Article 4 shall be payable on a country-by-country and Product-by-Productbasis from the First Commercial Sale of such Product until the expiration ofthe last-to-expire XOMA Patent Right in such country with respect to which aValid Claim covers the manufacture, use, sale, offer for sale, import or exportof such Product or the tenth anniversary of such First Commercial Sale,whichever is later.

4.3           Commercially Reasonable Efforts. DYAX will use itscommercially reasonable efforts to exploit the XOMA Patent Rights, generate anduse Licensed Antibody Phage Display Materials, conduct Antibody Phage Display,discover, identify, characterize, develop and commercially launch LicensedImmunoglobulins and Products and/or maximize the amounts available to be sharedwith XOMA pursuant to this Article 4. DYAX shall also use commerciallyreasonable efforts to collect or receive any payments or other considerationdue to it relating to any activities that would give rise to an obligationunder Section 4.2.

4.4           Payments; Currency. All payments due hereundershall be paid by wire transfer in United States dollars in immediatelyavailable funds to an account designated by XOMA. Payments required pursuant toSection 4.2 hereof shall be due and payable to XOMA when the corresponding NetSales are received by DYAX (or any joint venture or similar arrangement inwhich DYAX is a participant) and shall be paid within thirty (30) days of theend of each calendar quarter. If any currency conversion shall be required inconnection with the payment of any royalties hereunder, such conversion shallbe made by using the exchange rate for the purchase of U.S. dollars quoted inthe U.S. version of the Wall Street Journal on the last business day of thecalendar quarter to which such payments relate.

**Confidentialmaterials omitted and filed separately with the Securities and ExchangeCommission. An asterisk in brackets [*] denotes such omission.**

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4.5           Payment Reports. After the First Commercial Sale ofa Product on which royalties are required to be paid hereunder, DYAX shall makequarterly written reports to XOMA within thirty (30) days after the end of eachcalendar quarter, stating in each such report, by country, the number,description, and aggregate Net Sales of each Product sold during the calendarquarter. XOMA shall treat all such reports as Confidential Information of DYAX.Concurrently with the making of such reports, DYAX shall pay XOMA the amountsspecified in Section 4.2 hereof.

4.6          PaymentRecords and Inspection. DYAX shall keep complete, true and accurate booksof account and records for the purpose of determining the amounts payable underthis Agreement. Such books and records shall be kept at the principal place ofbusiness of DYAX for at least three (3) years following the end of the calendarquarter to which they pertain. Upon the written request of XOMA and not morethan once in each calendar year, DYAX shall permit an independent consultantappointed by XOMA and reasonably acceptable to DYAX to have access duringnormal business hours to such of the records of DYAX as may be reasonablynecessary to verify the accuracy of the royalty reports hereunder for any yearending not more than thirty-six (36) months prior to the date of such request,unless a discrepancy is found. The consultant shall disclose to XOMA only theresults and conclusions of its review and the specific details concerning anydiscrepancies. No other information shall be shared by the consultant withoutthe prior consent of DYAX unless disclosure is required by law, regulation orjudicial order. The consultant may be obliged to execute a reasonableconfidentiality agreement prior to commencing any such inspection. Inspectionsconducted under this Section 4.6 shall be at the expense of XOMA, unless anunderpayment exceeding five percent (5%) of the amount stated for the fullperiod covered by the inspection is identified, in which case all out-of-pocketcosts relating to the inspection will be paid promptly by DYAX. Anyunderpayments or unpaid amounts discovered by such inspections or otherwisewill be paid promptly by DYAX, with interest from the date(s) such amount(s)were due at a rate equal to the lesser of the prime rate reported by the Bankof America plus two percent (2%) or the highest interest rate permitted underapplicable law.

**ARTICLE 5.          CONFIDENTIALITY**

5.1           Confidential Information. Except as expresslyprovided herein, the parties agree that, for the term of this Agreement and forfive (5) years thereafter, the receiving party shall keep completely confidentialand shall not publish or otherwise disclose and shall not use for any purposeexcept for the purposes contemplated by this Agreement any ConfidentialInformation furnished to it by the disclosing party hereto, except to theextent that it can be established by the receiving party by written proof thatsuch Confidential Information:

(a)                                  was already known to the receiving party,other than under an obligation of confidentiality, at the time of disclosure;

(b)                                 was generally available to the public or otherwisepart of the public domain at the time of its disclosure to the receiving party;

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(c)                                  became generally available to the public orotherwise part of the public domain after its disclosure other than through anyact or omission of the receiving party in breach of this Agreement; or

(d)                                 was subsequently lawfully disclosed to thereceiving party by a person other than a party hereto.

5.2           Permitted Use and Disclosures. Each party heretomay use or disclose information disclosed to it by the other party to theextent such use or disclosure is reasonably necessary in complying withapplicable law or government regulations or conducting clinical trials; *provided, however,*that if a party isrequired to make any such disclosure of another party’s ConfidentialInformation, other than pursuant to a confidentiality agreement, it will givereasonable advance notice to the latter party of such disclosure and, will useits reasonable efforts to secure confidential treatment of such informationprior to its disclosure (whether through protective orders or otherwise).Attached hereto as Schedule 5.2 is a redacted copy of this Agreementwhich DYAX shall be free, without obtaining any consent from XOMA, to provideto Third Parties who indicate an interest in becoming a DYAX Collaborator or aDevelopment Partner of DYAX.

5.3           ConfidentialTerms. Except as expressly provided herein, each party agrees not to discloseany terms of this Agreement to any Third Party without the consent of the otherparty; *provided,*that disclosuresmay be made as required by securities or other applicable laws, or to a party’saccountants, attorneys and other professional advisors.

**ARTICLE 6.          REPRESENTATIONS AND WARRANTIES**

6.1           Representations and Warranties.

(a)           XOMA represents and warrants to DYAX that: (i) it is thesole and exclusive owner or exclusive licensee of all right, title and interestin the XOMA Patent Rights; (ii) XOMA has the legal right, authority and powerto enter into this Agreement; (iii) this Agreement shall constitute a valid andbinding obligation of XOMA enforceable in accordance with its terms; and (iv)the performance of obligations under this Agreement by XOMA shall not result ina breach of any agreements, contracts or other arrangements to which it is aparty.

(b)      DYAX represents and warrants to XOMA that: (i)it is the sole and exclusive owner or exclusive licensee of all right, titleand interest in the DYAX Patent Rights, (ii) DYAX has the legal right,authority and power to enter into this Agreement; (iii) this Agreement shallconstitute a valid and binding obligation of DYAX enforceable in accordancewith its terms; and (iv) the performance of obligations under this Agreement byDYAX shall not result in a breach of any agreements, contracts or otherarrangements to which it is a party.

6.2           Disclaimer.Nothing in this Agreement is or shall be construed as:

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(a)                                 A warranty or representation by XOMA or DYAXas to the validity or scope of any claim or patent within the XOMA PatentRights or the DYAX Patent Rights, as the case may be;

(b)                                A warranty or representation that anythingmade, used, sold, or otherwise disposed of under any license granted in thisAgreement is or will be free from infringement of any patent rights or otherintellectual property right of any Third Party;

(c)                                 An obligation to bring or prosecute actionsor suits against Third Parties for infringement of any of the XOMA PatentRights or the DYAX Patent Rights;

(d)                                An obligation to maintain any patent or tocontinue to prosecute any patent application included within the XOMA PatentRights or the DYAX Patent Rights in any country; or

(e)                                 Granting by implication, estoppel, orotherwise any licenses or rights under patents or other rights of XOMA, DYAX orThird Parties, regardless of whether such patents or other rights are dominantor subordinate to any patent within the XOMA Patent Rights or the DYAX PatentRights, as the case may be.

6.3           No Other Warranties. EXCEPT AS OTHERWISE SET FORTHIN SECTION 6.1 ABOVE, NEITHER PARTY HERETO MAKES ANY WARRANTIES WITH RESPECT TOANY OF THE PATENT RIGHTS, MATERIALS OR KNOW-HOW LICENSED HEREUNDER, EXPRESS ORIMPLIED, EITHER IN FACT OR BY OPERATION OF LAW, BY STATUTE OR OTHERWISE, ANDEACH PARTY SPECIFICALLY DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY OFMERCHANTABILITY, OF FITNESS FOR A PARTICULAR PURPOSE, OF VALIDITY OF SUCHPATENT RIGHTS, MATERIALS OR KNOW-HOW, ARISING FROM COURSE OF DEALING OR OFNON-INFRINGEMENT OF THE INTELLECTUAL PROPERTY RIGHTS OF ANY THIRD PARTY.

6.4           Certain Agreements.   DYAX represents and warrants that it has inits possession, and agrees that throughout the term of this Agreement it willmaintain in an accessible location, true, complete and legible copies of eachof the agreements set forth on Schedule 2.9 as in effect on the Effective Dateof the Original Agreement, including all schedules, exhibits and other similardocuments necessary for the correct interpretation of the provisions thereof.

**ARTICLE 7.          [RESERVED]**

**ARTICLE 8.          TERM AND TERMINATION**

8.1           Term. Subject to Sections 8.5 and 8.6 hereof, theterm of this Agreement will commence on the Effective Date and (a) with regardto the license rights granted to XOMA by DYAX pursuant to

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Article 3, this Agreementshall remain in full force and effect until the last to expire of the DYAXPatent Rights, unless earlier terminated by DYAX pursuant to Section 8.2, 8.3or 8.4;*provided, however,*thatupon such expiration and absent any earlier termination pursuant to Section8.2, 8.3 or 8.4, XOMA shall have a royalty-free, fully paid up right and licenseto continue to use the DYAX Materials as permitted by Article 3; and (b) withregard to the license and other rights granted to DYAX and any DYAX Collaboratorsor Development Partners of DYAX by XOMA pursuant to Article 2, this Agreementshall remain in full force and effect until the last to expire of the XOMAPatent Rights or the tenth anniversary of the First Commercial Sale of the lastProduct to be launched, whichever is later, unless earlier terminated by XOMApursuant to Section 8.2, 8.3 or 8.4; *provided,however,*that, to the extent any of the XOMA Know-How is notincluded in the XOMA Patent Rights, upon such expiration and absent any earliertermination pursuant to Section 8.2, 8.3 or 8.4, DYAX shall have aroyalty-free, fully paid up right and license to continue to use the XOMAKnow-How as permitted by Article 2 .

8.2           Terminationfor Material Breach. With regard to (a) the license rights granted to XOMAby DYAX pursuant to Article 3, or (b) the license and other rights granted toDYAX and any DYAX Collaborators or Development Partners of DYAX by XOMApursuant to Article 2, this Agreement may be terminated by either DYAX or XOMAupon any material breach by XOMA or DYAX, as the case may be, of any materialobligation or condition of the Agreement, in either case effective fifteen (15)days after giving notice to the breaching party of such termination in the caseof a payment breach and sixty (60) days after giving written notice to thebreaching party of such termination in the case of any other breach, whichnotice shall describe such breach in reasonable detail. The foregoingnotwithstanding, if such breach is cured or shown to be non-existent within theaforesaid fifteen (15) or sixty (60) day period, the notice shall be deemedautomatically withdrawn and of no effect and the notifying party shall providewritten notice to the breaching party of the withdrawal. A termination of thebreaching party’s rights and licenses pursuant to this Section 8.2 shall noteffect the non-breaching party’s rights and licenses, which shall continueuntil otherwise terminated in accordance with this Agreement.

8.3           Termination for Insolvency.  If voluntary or involuntary proceedings by oragainst either party are instituted in bankruptcy under any insolvency law, ora receiver or custodian is appointed for either party, or proceedings areinstituted by or against either party for corporate reorganization or thedissolution of such party, which proceedings, if involuntary, shall not havebeen dismissed within sixty (60) days after the date of filing, or if eitherparty makes an assignment for the benefit of creditors, or substantially all ofthe assets of either party are seized or attached and not released within sixty(60) days thereafter, the other party may immediately terminate this Agreementeffective upon notice of such termination.

8.4           Contested Validity. If DYAX, a DYAX Collaborator orany person or entity controlled by any of the foregoing contests the validityor enforceability of any of the XOMA Patent Rights licensed hereunder, XOMAshall have the right to terminate all of the rights and licenses hereby grantedto DYAX and any DYAX Collaborator under the XOMA Patent Rights; *provided, however,*that in the event aDYAX Collaborator contests the validity or enforceability of any of the XOMAPatent Rights licensed hereunder other than at the direction, and without theassistance or other involvement, of DYAX, then the foregoing termination rightof XOMA shall apply only to the rights hereby granted to such DYAX 

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Collaborator. If XOMA or anyperson or entity controlled by XOMA contests the validity or enforceability ofany of the DYAX Patent Rights licensed hereunder, DYAX shall have the right toterminate all of the rights and licenses hereby granted to XOMA under the DYAXPatent Rights.

8.5           Effect of Termination.

(a)            Termination of this Agreement shall not release any partyhereto from any liability which, at the time of such termination, has alreadyaccrued to the other party or which is attributable to a period prior to suchtermination nor preclude either party from pursuing any rights and remedies itmay have hereunder or at law or in equity with respect to any breach of thisAgreement. It is understood and agreed that monetary damages may not be asufficient remedy for any breach of this Agreement and that the non-breachingparty may be entitled to injunctive relief as a remedy for any such breach.Such remedy shall not be deemed to be the exclusive remedy for any such breachof this Agreement, but shall be in addition to all other remedies available atlaw or in equity.

(b)           Upon any terminationof this Agreement, DYAX and XOMA shall promptly return to the other party allConfidential Information received from the other party (except that each partymay retain one copy for its files solely for the purpose of determining itsrights and obligations hereunder).

(c)           Except as expresslyprovided in Sections 8.1 and 8.2, all licenses granted under Article 2 hereofshall terminate and be of no further effect upon the termination of thisAgreement.

8.6           Survival.Sections 2.6(c), 2.7, 2.8, 2.9, 3.3, 3.4, 3.5, 4.2, 4.4, 4.5, 4.6, 8.2, 8.5 and8.6, and Articles 1, 5, 6 and 9 of this Agreement shall survive any terminationhereof. Without limiting the foregoing, Article 2 of this Agreement shallsurvive any termination hereof by DYAX, and Article 3 of this Agreement shallsurvive any termination hereof by XOMA.

**ARTICLE 9.          MISCELLANEOUS PROVISIONS**

9.1           Governing Laws. This Agreement and any dispute,including without limitation any arbitration, arising from the performance orbreach hereof shall be governed by and construed and enforced in accordancewith the laws of the state of New York, without reference to conflicts of lawsprinciples.

9.2           Assignment. Neither party may transfer or assignthis Agreement, directly or indirectly, or any of its rights hereunder withoutthe prior written consent of the other party, other than (a) to one or moreAffiliates, (b) to a successor of XOMA Ltd. under a Change in Control of XOMALtd. or to a successor of DYAX Corp. under a Change in Control of DYAX Corp. towhich Section 9.3 does not apply, or (c) to a Third Party in connection withthe transfer or sale of all or substantially all or its business relating toantibody selection, development and production and the provision of relatedservices (other than (i) with respect to such a transfer or sale by DYAX, sucha transfer or sale to any Person listed or described in Section 9.3 and (ii)with respect to such a transfer or sale by XOMA, such a transfer or sale to[*]. Any such attempted transfer or assignment in violation of this Section 9.2shall be void; *provided,*that inthe event of a permitted Change in Control, the original party’s (or itssuccessor’s) obligations hereunder shall 

**Confidentialmaterials omitted and filed separately with the Securities and ExchangeCommission. An asterisk in brackets [*] denotes such omission.**

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continue. This Agreementshall be binding upon and inure to the benefit of the parties and theirpermitted successors and assigns.

9.3           Certain Changes in Control. Notwithstanding anyother provision of this Agreement to the contrary, the license and other rightsgranted pursuant to Article 2 shall automatically terminate, without furtheraction by the parties, in the event of (a) a transaction or series of relatedtransactions in which [*] is a party and which results in a Change of Controlof DYAX, or (b) a transaction or series of related transactions in which DYAXis a party and which results in a Change in Control of a person or entity describedin clause (a) above.

9.4           Waiver. No waiver of any rights shall be effectiveunless consented to in writing by the party to be charged and the waiver of anybreach or default shall not constitute a waiver of any other right hereunder orany subsequent breach or default.

9.5           Severability. In the event that any provisions ofthis Agreement are determined to be invalid or unenforceable by a court ofcompetent jurisdiction, the remainder of the Agreement shall remain in fullforce and effect without said provision.

9.6           Notices. All notices, requests and othercommunications hereunder shall be in writing and shall be delivered or sent ineach case to the respective address specified below, or such other address asmay be specified in writing to the other party hereto, and shall be effectiveon receipt:
| DYAX:                                                |   | DYAX Corp.                       |
|------------------------------------------------------|--------|----------------------------------|
|                                                 |   | 300 Technology  Square           |
|                                                 |   | Cambridge, MA  02139             |
|                                                 |   | U.S.A.                           |
|                                                 |   | Attn: General  Counsel           |
|                                                 |   |                             |
| XOMA:                                                |   | XOMA Ireland Limited             |
|                                                 |   | Shannon Airport  House           |
|                                                 |   | Shannon, County  Clare           |
|                                                 |   | Ireland                          |
|                                                 |   | Attn: Company  Secretary         |
|                                                 |   |                             |
| with a copy  (which shall not constitute notice) to: |
|                                                 |   |                             |
|                                                 |   | Cahill Gordon  & Reindel LLP |
|                                                 |   | 80 Pine Street                   |
|                                                 |   | New York, NY  10005              |
|                                                 |   | U.S.A.                           |
|                                                 |   | Attn: Geoffrey  E. Liebmann      |

 

**Confidentialmaterials omitted and filed separately with the Securities and ExchangeCommission. An asterisk in brackets [*] denotes such omission.**

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9.7           Independent Contractors. Both parties areindependent contractors under this Agreement. Nothing contained in thisAgreement is intended nor is to be construed so as to constitute XOMA or DYAX as partners or joint venturers with respectto this Agreement.  Except as expresslyprovided herein, neither party shall have any express or implied right orauthority to assume or create any obligations on behalf of or in the name ofthe other party or to bind the other party to any other contract, agreement, orundertaking with any third party.

9.8           Compliance with Laws. In exercising their rightsunder this license, the parties shall comply in all material respects with therequirements of any and all applicable laws, regulations, rules and orders ofany governmental body having jurisdiction over the exercise of rights underthis Agreement.

9.9           Bankruptcy. All rights and licenses granted underor pursuant to this Agreement by one party to the other are, for all purposesof Section 365(n) of Title XI of the United States Code (“Title XI”),licenses of rights to “intellectual property” as defined in Title XI. Duringthe term of this Agreement each party shall create and maintain current copiesto the extent practicable of all such intellectual property. If a bankruptcyproceeding is commenced by or against one party under Title XI, the other partyshall be entitled to a copy of any and all such intellectual property and allembodiments of such intellectual property, and the same, if not in thepossession of such other party, shall be promptly delivered to it (a) upon suchparty’s written request following the commencement of such bankruptcy proceeding,unless the party subject to such bankruptcy proceeding, or its trustee orreceiver, elects within thirty (30) days to continue to perform all of itsobligations under this Agreement, or (b) if not delivered as provided underclause (a) above, upon such other party’s request following the rejection ofthis Agreement by or on behalf of the party subject to such bankruptcyproceeding.  If a party has takenpossession of all applicable embodiments of the intellectual property of theother party pursuant to this Section 9.9 and the trustee in bankruptcy of theother party does not reject this Agreement, the party in possession of suchintellectual property shall return such embodiments upon request. If a partyseeks or involuntarily is placed under Title XI and the trustee rejects thisAgreement as contemplated under 11 U.S.C. 365(n)(1), the other party herebyelects, pursuant to Section 365(n) of Title XI, to retain all rights granted toit under this Agreement to the extent permitted by law.

9.10         Useof Name. Neither party shall use the name or trademarks of the other party,except to the extent that a party is permitted to use the ConfidentialInformation of the other party pursuant to Article 5, without the prior writtenconsent of such other party.

9.11         FurtherActions. Each party agrees to execute, acknowledge and deliver such furtherinstruments, and do such other acts, as may be necessary and appropriate inorder to carry out the purposes and intent of this Agreement.

9.12         EntireAgreement: Amendment. This Agreement, together with the agreement of XOMAcontained in that certain letter agreement, dated July 24, 2006 (whichagreement shall also have effect with respect to this Agreement), constitutesthe entire and exclusive Agreement between the parties with respect to thesubject matter hereof and supersedes and cancels all previous discussions,agreements, 

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commitments and writings in respect thereof. No amendment or additionto this Agreement shall be effective unless reduced to writing and executed bythe authorized representatives of the parties.

9.13         Arbitration.

(a)            Solelywith respect to any dispute between the parties to this Agreement (other thanany dispute which arises out of or relates to infringement, validity and/orenforceability of the XOMA Patent Rights or the DYAX Patent Rights) upon ten(10) days written notice, any party involved in the dispute may initiatearbitration by giving notice to that effect to the other party or partiesinvolved in the dispute and by filing the notice with the American ArbitrationAssociation or its successor organization (“AAA”) in accordance with itsCommercial Arbitration Rules. Such dispute shall then be settled by arbitrationin New York, New York, in accordance with the Commercial Arbitration Rules ofthe AAA or other rules agreed to by the parties involved in the dispute, by apanel of three neutral arbitrators, who shall be selected by the partiesinvolved in the dispute using the procedures for arbitrator selection of theAAA.

(b)           The parties acknowledge that this Agreement evidences atransaction involving interstate commerce. Insofar as it applies, the UnitedStates Arbitration Act shall govern the interpretation of, enforcement of, andproceedings pursuant to the arbitration clause in this Agreement. Exceptinsofar as the United States Arbitration Act applies to such matters, theagreement to arbitrate set forth in this Section 9.13 shall be construed, andthe legal relations among the parties shall be determined in accordance with,the substantive laws of the State of New York.

(c)           The panel shall render its decision and award, including astatement of reasons upon which such award is based, within thirty (30) daysafter the arbitration hearing. The decision of the panel shall be determined bymajority vote among the arbitrators, shall be in writing and shall be bindingupon the parties involved in the dispute, final and non-appealable.  Judgment upon the award rendered by the panelmay be entered in any court having jurisdiction thereof in accordance withSection 9.14(a).

(d)           Except as provided under the United States Arbitration Actand with respect to the infringement, validity and/or enforceability of theXOMA Patent Rights or the DYAX Patent Rights, no action at law or in equitybased upon any dispute that is subject to arbitration under this Section 9.13shall be instituted.

(e)           All expenses of any arbitration pursuant to this Section9.13, including fees and expenses of the parties’ attorneys, fees and expensesof the arbitrators, and fees and expenses of any witness or the cost of anyproof produced at the request of the arbitrators, shall be paid by thenon-prevailing party.

9.14         Venue;Jurisdiction.

(a)           Any action orproceeding brought by either party seeking to enforce any provision of, orbased on any right arising out of, this Agreement must be brought against anyof the parties in 

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thecourts of the State of New York. Each party (i) hereby irrevocably submits tothe jurisdiction of the state courts of the State of New York and to the jurisdictionof any United States District Court in the State of New York, for the purposeof any suit, action, or other proceeding arising out of or based upon thisAgreement or the subject matter hereof brought by any party or its successorsor assigns, (ii) hereby waives, and agrees not to assert, by way of motion, asa defense, or otherwise, in any such suit, action, or proceeding, any claimthat it is not subject personally to the jurisdiction of the above-namedcourts, that its property is exempt or immune from attachment or execution,that the suit, action or proceeding is brought in an inconvenient forum, thatthe venue of the suit, action, or proceeding is improper or that this Agreementor the subject matter hereof may not be enforced in or by such court, and (iii)hereby waives and agrees not to seek any review by any court of any otherjurisdiction that may be called upon to grant an enforcement of the judgment ofany such New York state or federal court.

(b)           Process in any action or proceeding seeking to enforce anyprovision of, or based on any right arising out of, this Agreement may beserved on any party anywhere in the world. Each party consents to service ofprocess by registered mail at the address to which notices are to be givenpursuant to Section 9.6. Nothing herein shall affect the right of a party toserve process in any other manner permitted by applicable law. Each partyfurther agrees that final judgment against it in any such action or proceedingarising out of or relating to this Agreement shall be conclusive and may beenforced in any other jurisdiction within or outside the United States ofAmerica by suit on the judgment, a certified or exemplified copy of which shallbe conclusive evidence of the fact and of the amount of its liability.

(c)           Each party agrees that it shall not, and that it shallinstruct those in its control not to, take any action to frustrate or preventthe enforcement of any writ, decree, final judgment, award (arbitral orotherwise) or order entered against it with respect to this Agreement, the XOMAPatent Rights or the DYAX Patent Rights and shall agree to be bound thereby asif issued or executed by a competent judicial tribunal having personaljurisdiction situated in its country of residence or domicile.

9.15         Counterparts.This Agreement may be executed in two or more counterparts, each of which shallbe deemed an original, but all of which together shall constitute one and thesame instrument.

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IN WITNESS WHEREOF, XOMA andDYAX have executed this Agreement in duplicate originals by duly authorizedofficers.
| **DYAX CORP.** |                                             | **XOMA IRELAND LIMITED** |
|----------------|--------------------------------------------------|--------------------------|
| ** **     |                                             | ** **               |
| ** **     |                                             | ** **               |
| ** **     |                                             | ** **               |
| By:            | /s/ Ivana Magovcevic-Liebisch                    |                     | By: | /s/ Alan Kane |   |
| Name:          | Ivana Magovcevic-Liebisch                        |                     | Alan Kane, Director |
| Title:         | General Counsel and Executive Vice               |                     | duly authorized for and on behalf of XOMA |
|           |    President, Corporate Communications |                     | Ireland Limited in the presence of: |
|           |                                             |                     |   |
|           |                                             |                     | /s/ Niamh Coghlan |   |
|                |                                                  |                          |  |  |  |  |

 

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SCHEDULE 1.9

Dyax Patent Rights

 
| Country       | ** ** | **Application/  Publication No.**    | ** ** | **Filing Date**  | ** ** | **Patent No.**  | ** ** | **Issue Date**         | ** ** | **Expiration  Date** |
|---------------|------------|--------------------------------------|------------|------------------|------------|-----------------|------------|------------------------|------------|----------------------|
| US            |       | 07/664,989                           |       | 03/01/91         |       | 5,223,409       |       | 06/29/93               |       | 06/29/10             |
| US            |       | 08/009,319                           |       | 01/26/93         |       | 5,403,484       |       | 04/04/95               |       | 04/04/12             |
| US            |       | 08/057,667                           |       | 06/18/93         |       | 5,571,698       |       | 11/05/96               |       | 06/29/10             |
| US            |       | 08/415,922                           |       | 04/03/95         |       | 5,837,500       |       | 11/17/98               |       | 06/29/10             |
| US            |       | 09/781,988                           |       | 02/14/01         |       | 6,979,538       |       | 12/27/05               |       | 06/29/10             |
| US            |       | 09/893,878                           |       | 06/29/01         |       |            |       |                   |       |                 |
| US            |       | 10/126,544                           |       | 04/22/02         |       |            |       |                   |       |                 |
| US            |       | 10/207,797                           |       | 07/31/02         |       |            |       |                   |       |                 |
| US            |       | 08/821,498                           |       | 03/21/97         |       | 6,326,155       |       | 12/04/01               |       |                 |
|  

PCT   |       | PCT/US89/03731   W090/02809 (pub)    |       |  

09/01/89 |       |            |       |  

National Phase |       |                 |
| EP            |       | 89910702.3                           |       | 09/01/89         |       | EP 436,597      |       | 04//02/97              |       | Revoked              |
|  

EP    |       | Divisional 96/112867.5  768377 (pub) |       |  

09/01/89 |       |            |       |                   |       |  

Abandoned    |
| EP            |       | Divisional 00106289.2                |       | 09/01/89         |       |            |       |                   |       | Abandoned            |
|  

EP    |       | Divisional 05000796.2   EP1541682    |       |  

09/01/89 |       |            |       |                   |       |  

Published    |
|  

Japan |       | 510087/1989   JP4502700 (pub)        |       |  

09/01/89 |       |  

3771253 |       |  

02/17/06       |       |  

09/01/09     |
| Canada        |       | 610,176                              |       | 09/01/89         |       | 1,340,288       |       | 01/27/99               |       | 09/01/09             |
| Canada        |       | 2105300                              |       | 02/27/92         |       | 2105300         |       | 09/02/1992             |       | 02/27/12             |
| Ireland       |       | IR89/2834                            |       | 09/04/89         |       |            |       |                   |       |                 |
| Israel        |       | 91501                                |       | 09/01/89         |       | 91501           |       | 06/11/98               |       | 09/01/09             |
| Israel        |       | Divisional 120,941                   |       | 09/01/89         |       | 120,941         |       | 09/20/2005             |       | 09/01/09             |
| Israel        |       | Divisional 120,940                   |       | 09/01/89         |       | 120,940         |       | 09/20/2005             |       | 09/01/09             |
| Israel        |       | Divisional 120,939                   |       | 09/01/89         |       | 120,939         |       | 10/25/2001             |       | 09/01/09             |
|  

PCT   |       | US92/01539   W092/15679 (pub)        |       |  

02/28/92 |       |            |       |  

National Phase |       |                 |
| EP            |       | 92/908799.7                          |       | 02/28/92         |       | 0 573 611       |       | 03/17/04               |       | 02/28/12             |
| EP            |       | 04/006079.0                          |       | 02/28/92         |       |            |       |                   |       |                 |
| Japan         |       | 508216/1992                          |       | 02/28/92         |       | 3447731         |       | 07/04/03               |       | 02/28/12             |
| Japan         |       | 130929                               |       | 05/09/03         |       |            |       |                   |       |                 |
| Japan         |       | 507558                               |       | 02/27/92         |       |            |       |                   |       |                 |

 

24

----

SCHEDULE 1.24

XOMAPatent Rights

**Title**: **Modular Assembly ofAntibody Genes, Antibodies Prepared Thereby and Use**

Inventors**:**             Robinson,Liu, Horwitz, Wall, Better

1)                                      Based onPCT/US86/02269, which is a continuation-in-part of U.S. Application No.06/793,980 filed November 1, 1985 (abandoned).
| COUNTRY        |   | APPLICATION NO.                       |   | PATENT NO.          |
|----------------|--------|---------------------------------------|--------|---------------------|
| Australia      |   | 65981/86                              |   | Issued 606,320      |
| Denmark        |   | 3385/87                               |   | Issued PR 175680 B1 |
| Taiwan         |   | 75105650                              |   | Expired             |
| *United States |   | 06/793,980                            |   |                |
| *United States |   | U.S. National Phase of PCT/US86/02269 |   |                |

----

*Cases abandoned in favor of a continuing application.

2)             Based on PCT/US88/02514, whichcorresponds to U.S. Application No. 07/077,528, which is a continuation-in-partPCT/US86/02269 (abandoned), which is a continuation-in-part of U.S. ApplicationNo. 06/793,980 (abandoned).
| COUNTRY                     | ** ** | **APPLICATION NO.** | ** ** | **PATENT NO.**       |
|-----------------------------|------------|---------------------|------------|----------------------|
| Australia                   |       | 23244/88            |       | Issued 632,462       |
| Canada                      |       | 572,398             |       | Granted 1,341,235    |
| Denmark                     |       | 192/90              |       | Granted 174824       |
| Denmark                     |       | 200301155           |       | Granted PR 175654 B1 |
| Denmark                     |       | 200301156           |       | Granted PR 175581 B1 |
| Europe                      |       | EP 88907510.7       |       | Granted EP 0371998   |
| Austria                     |       | EP 88907510.7       |       | Granted EP 0371998   |
| Belgium                     |       | EP 88907510.7       |       | Granted EP 0371998   |
| France                      |       | EP 88907510.7       |       | Granted EP 0371998   |
| Germany                     |       | EP 88907510.7       |       | Granted P 3888186.1  |
| Italy                       |       | EP 88907510.7       |       | Granted EP 0371998   |
| Luxembourg                  |       | EP 88907510.7       |       | Granted EP 0371998   |
| Netherlands                 |       | EP 88907510.7       |       | Granted EP 0371998   |
| Sweden                      |       | EP 88907510.7       |       | Granted EP 0371998   |
| Switzerland/  Liechtenstein |       | EP 88907510.7       |       | Granted EP 0371998   |
| United Kingdom              |       | EP 88907510.7       |       | Granted EP 0371998   |
| Europe                      |       | EP 93100041.8       |       | Granted EP 0550400   |
| Austria                     |       | EP 93100041.8       |       | Granted EP 0550400   |
| Belgium                     |       | EP 93100041.8       |       | Granted EP 0550400   |
| France                      |       | EP 93100041.8       |       | Granted EP 0550400   |
| Germany                     |       | EP 93100041.8       |       | Granted P 3855421.6  |
| Italy                       |       | EP 93100041.8       |       | Granted EP 0550400   |
| Luxembourg                  |       | EP 93100041.8       |       | Granted EP 0550400   |
| Netherlands                 |       | EP 93100041.8       |       | Granted EP 0550400   |
| Sweden                      |       | EP 93100041.8       |       | Granted EP 0550400   |
| Switzerland/  Liechtenstein |       | EP 93100041.8       |       | Granted EP 0550400   |
| United Kingdom              |       | EP 93100041.8       |       | Granted EP 0550400   |
| Europe                      |       | EP 95119798.7       |       | Granted EP 0731167   |
| Austria                     |       | EP 95119798.7       |       | Granted EP 0731167   |
| Belgium                     |       | EP 95119798.7       |       | Granted EP 0731167   |
| France                      |       | EP 95119798.7       |       | Granted EP 0731167   |
| Germany                     |       | EP 95119798.7       |       | Granted P 3856440.12 |
| Italy                       |       | EP 95119798.7       |       | Granted EP 0731167   |
| Luxembourg                  |       | EP 95119798.7       |       | Granted EP 0731167   |
| Netherlands                 |       | EP 95119798.7       |       | Granted EP 0731167   |
| Sweden                      |       | EP 95119798.7       |       | Granted EP 0731167   |
| Switzerland/  Liechtenstein |       | EP 95119798.7       |       | Granted EP 0731167   |
| United Kingdom              |       | EP 95119798.7       |       | Granted EP 0731167   |
| Japan                       |       | 506481/88           |       | Granted 2991720      |
| *United States              |       | 07/077,528          |       |                 |

----

*Cases abandoned in favor of a continuing application.

25

----

3)                                      Basedon U.S. Application No. 07/501,092 filed March 29, 1990, which is a continuation-in-partof U.S. Application No. 07/077,528 (Modular Assembly of Antibody Genes,Antibodies Prepared Thereby and Use; Robinson, Liu, Horwitz, Wall, Better) andof U.S. Application No. 07/142,039 (Novel Plasmid Vector with Pectate LyaseSignal Sequence; Lei, Wilcox).
| COUNTRY        | ** ** | **APPLICATION NO.** | ** ** | **PATENT NO.** |
|----------------|------------|---------------------|------------|----------------|
| *United States |       | 07/501,092          |       |           |
| *United States |       | 07/987,555          |       |           |
| *United States |       | 07/870,404          |       |           |
| *United States |       | 08/020,671          |       |           |
| *United States |       | 09/722,425          |       | Abandoned      |
| *United States |       | 09/722,315          |       | Abandoned      |
| United States  |       | 08/235,225          |       | 5,618,920      |
| United States  |       | 08/299,085          |       | 5,595,898      |
| United States  |       | 08/472,691          |       | 6,204,023      |
| United States  |       | 08/467,140          |       | 5,698,435      |
| United States  |       | 08/450,731          |       | 5,693,493      |
| United States  |       | 08/466,203          |       | 5,698,417      |
| United States  |       | 10/040,945          |       | Pending        |

----

*Cases abandoned in favor of a continuing application.

**Title****:**      **AraB Promoters and Method of Producing Polypeptides, IncludingCecropins, by Microbiological Techniques**

26

----

Inventors:              Lai,Lee, Lin, Ray, Wilcox

Based on PCT/US86/00131, whichis a continuation-in-part of U.S. Application No. 06/695,309 filed January 28,1985 (abandoned).
| COUNTRY                     | ** ** | **APPLICATION NO.** | ** ** | **PATENT NO.**        |
|-----------------------------|------------|---------------------|------------|-----------------------|
| Europe                      |       | EP 86900983.7       |       | Granted EP 0211047    |
| Austria                     |       | EP 86900983.7       |       | Granted EP 0211047    |
| Belgium                     |       | EP 86900983.7       |       | Granted EP 0211047    |
| France                      |       | EP 86900983.7       |       | Granted EP 0211047    |
| Germany                     |       | EP 86900983.7       |       | Granted P3689598.9-08 |
| Italy                       |       | EP 86900983.7       |       | Granted EP 0211047    |
| Luxembourg                  |       | EP 86900983.7       |       | Granted EP 0211047    |
| Netherlands                 |       | EP 86900983.7       |       | Granted EP 0211047    |
| Sweden                      |       | EP 86900983.7       |       | Granted EP 0211047    |
| Switzerland/  Liechtenstein |       | EP 86900983.7       |       | Granted EP 0211047    |
| United Kingdom              |       | EP 86900983.7       |       | Granted EP 0211047    |
| Finland                     |       | 863891              |       | Granted 94774         |
| Japan                       |       | 500818/86           |       | Granted 2095930       |
| Japan                       |       | 094753/94           |       | Granted 2121896       |
| Norway                      |       | 863806              |       | Granted 175870        |
| *United States              |       | 06/695,309          |       |                  |
| *United States              |       | 06/797,472          |       |                  |
| United States               |       | 07/474,304          |       | Granted 5,028,530     |

----

*Casesabandoned in favor of a continuing application.

**Title:**      **Novel Plasmid Vector with Pectate Lyase Signal Sequence**

Inventors:              Lei,Wilcox

Based on U.S.Application  No. 07/142,039 filed January11, 1988 and PCT/US89/00077.
| COUNTRY                     | ** ** | **APPLICATION NO.** | ** ** | **PATENT NO.**        |
|-----------------------------|------------|---------------------|------------|-----------------------|
| Australia                   |       | 29377/89            |       | Issued/627443         |
| Canada                      |       | 587,885             |       | 1,338,807             |
| Europe                      |       | EP 89901763.6       |       | Granted EP 0396612    |
| Austria                     |       | EP 89901763.6       |       | Granted EP 0396612    |
| Belgium                     |       | EP 89901763.6       |       | Granted EP 0396612    |
| France                      |       | EP 89901763.6       |       | Granted EP 0396612    |
| Germany                     |       | EP 89901763.6       |       | Granted 689 26 882 T2 |
| Italy                       |       | EP 89901763.6       |       | Granted EP 0396612    |
| Luxembourg                  |       | EP 89901763.6       |       | Granted EP 0396612    |
| Netherlands                 |       | EP 89901763.6       |       | Granted EP 0396612    |
| Sweden                      |       | EP 89901763.6       |       | Granted EP 0396612    |
| Switzerland/  Liechtenstein |       | EP 89901763.6       |       | Granted EP 0396612    |
| United Kingdom              |       | EP 89901763.6       |       | Granted EP 0396612    |
| Japan                       |       | 501661/89           |       | Granted 2980626       |
| *United States              |       | 07/142,039          |       |                  |
| United States               |       | 08/472,696          |       | 5,846,818             |
| United States               |       | 08/357,234          |       | 5,576,195             |

----

*Casesabandoned in favor of a continuing application.

27

----

SCHEDULE 2.2

Transfer of XOMA Materials

[*]

28

----

SCHEDULE 2.9

Third Parties and Activities

[*]

29

----

SCHEDULE 3.3

Dyax Materials

[*]

30

----

SCHEDULE 5.2

Redacted Agreement

31

----