AMENDED AND RESTATED LICENSE AGREEMENT

Exhibit 10.18 (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 this Agreement ”), is entered into by and between XOMA Ireland Limited, a company with limited liability organized under the laws of the Republic of Ireland having offices at Shannon Airport House, Shannon, County Clare, Ireland (with its Affiliates, “ XOMA ”) and DYAX Corp., a corporation organized under the 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 patent rights and know-how relating to bacterial cell expression, and DYAX wishes to acquire non-exclusive licenses under such patent rights and know-how; and

B.            DYAX is the owner or exclusive licensee of certain patent rights relating to phage display technologies (generally known as the Ladner and related patent rights), and XOMA wishes to acquire non-exclusive licenses under 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 Original Agreement ”), under which (i) XOMA granted to DYAX certain non-exclusive licenses to engage in certain research, development and commercial activities, and (ii) DYAX granted to XOMA certain non-exclusive licenses to engage in certain research, development and commercial activities (the “ Original Agreement ”); and

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

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

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

ARTICLE 1.    DEFINITIONS

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

Confidential materials omitted and filed separately with the Securities and Exchange
Commission. An asterisk in brackets [*] denotes such omission.

1.1           “ Affiliate ” means any corporation or other entity which is directly or indirectly controlling, controlled by or under common control 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 cause the direction of the management or policies of the subject corporation or other entity, whether through the ownership of voting securities, by agreement or otherwise.

1.2            “ Antibody Phage Display ” means the authorized use of Licensed Antibody Phage Display Materials to conduct Research and Development.

1.3            “ Change in Control ” means, with respect to Dyax Corp. or XOMA Ltd., any transaction or series of transactions as a result of which any person or group (as defined under the U.S. Securities Exchange Act of 1934, as amended) becomes, directly or indirectly, the beneficial owner of more than fifty percent (50%) of the total voting power of such entity’s equity securities 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 antibody phage display products or immunoglobulin or antibody phage display materials, the out-licensing, commercial manufacture, sale, offer for sale, import for sale or export for sale of such immunoglobulin or antibody phage display services, libraries, products and materials.

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

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

1.7            “ Dispose ” means to transfer, assign, lease, or in any other fashion dispose of control, ownership or possession, but shall not mean to license or sell. “ Disposition ” shall have the correlative meaning.

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

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

1.9           “ DYAX Patent Rights ” means the patent applications and patents listed on Schedule 1.9 hereto and, solely to the extent any Valid Claim would cover or be included in the license grants provided for herein, all divisions, continuations, continuations-in-part, applications claiming priority thereto, and substitutions thereof; all foreign patent applications corresponding to the preceding applications; all U.S. and foreign patents issuing on any of the preceding applications, including extensions, reissues and re-examinations; and any other patent rights owned or licensed by DYAX, whether now existing or obtained in the future, which DYAX has the right to license or sublicense and which would be infringed by the activities of XOMA contemplated 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 in the future, owned or controlled by DYAX containing a claim that is dominating over the foregoing patent rights (i.e., is necessarily infringed by the practicing of a claim in one of the foregoing applications).

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

1.11         “ Immunoglobulin ” means any molecule, including without limitation, full immunoglobulin molecules (e.g., IgG, IgM, IgE, IgA and IgD molecules) and ScFv, Fv and Fab molecules, that has an amino acid sequence by virtue of which it specifically interacts with an antigen and wherein that amino acid sequence consists essentially of a functionally operating region of an antibody variable region including, without limitation, any naturally occurring 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 the exclusive control of DYAX, which encodes at least one Immunoglobulin and which is contained in filamentous bacteriophage and/or bacteriophage or phagemid cloning vectors capable of propagation in bacteria; or (ii) any collection or library of bacteriophage, created by or under the exclusive control of DYAX, wherein an Immunoglobulin is expressed as a fusion protein comprising an Immunoglobulin or at least a functionally operating region of an antibody variable region and an outer surface polypeptide of a bacteriophage. For the avoidance of doubt, and without expanding the definition thereof, specifically excluded from the definition of Licensed Antibody Phage Display Materials are (x) any article of manufacture or composition of matter suitable for display, expression or secretion of an Immunoglobulin in or from any organism or system other than bacteria and (y) any materials or composition of matter otherwise meeting the definition of Licensed Antibody Phage

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Display Materials but created by or under the control of any entity, other than DYAX, engaged in a Commercial Antibody Phage Display Business; provided, that, notwithstanding the foregoing, any materials or composition of matter otherwise meeting the definition of Licensed Antibody Phage Display Materials but created by or under the exclusive control of a DYAX Collaborator shall constitute Licensed Antibody Phage Display Materials, but only to the extent derived by such DYAX Collaborator exclusively from Licensed Antibody Phage Display Materials created by or under the exclusive control of DYAX and properly transferred by DYAX to such DYAX Collaborator in accordance with the applicable provisions of this Agreement and such DYAX Collaborator acknowledges that the transfer restrictions and other provisions hereof apply thereto.

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

1.14          “ Licensed Immunoglobulin Information ” means any data, know-how or other information relating, concerning or pertaining to a Licensed Immunoglobulin, including, without limitation, data, know-how or other information characterizing or constituting such Licensed Immunoglobulin’s polynucleotide or amino acid sequence, purported function or utility, antigen binding affinity, or physical or biochemical property.

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

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

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

(c)                                   Amounts repaid or credited by reason of rejections, defects, recalls or returns or because of rebates or retroactive price reduction; and

(d)                                  Freight, transportation and insurance.

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

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

1.17         “ Research and Development ” means the identification, selection, isolation, purification, characterization, study and/or testing of an Immunoglobulin for any purpose, including, without limitation, any activities relating to the discovery and development of human therapeutic or diagnostic products. Included within the definition of “Research and Development” shall be all in vitro screening or assays customarily performed in pre-clinical and clinical research and uses associated 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 or industrial manufacture or any activities solely directed to the creation of such capacities.

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

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

1.20         “ Valid Claim ” means (i) a claim of an issued and unexpired 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 a court of competent jurisdiction from which no appeal may be taken, and which has not been disclaimed or admitted to be invalid or unenforceable through reissue or otherwise, or (ii) a claim of a pending patent application within the 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 a functional Immunoglobulin in a prokaryote.

1.22         “ XOMA Field of Use ” means all fields.

1.23         “ XOMA Know-How ” means unpatented and/or unpatentable technical information, including ideas, concepts, inventions, discoveries, data, designs, formulas, specifications, procedures for experiments and tests and other protocols, results of experimentation and testing, fermentation and purification techniques, and assay protocols, whether now existing or obtained in the future, owned by XOMA which XOMA has the right to license or sublicense and which may be necessary for the practice of the applicable XOMA Patent Rights or which would be misappropriated by the activities of DYAX or the DYAX Collaborators contemplated hereunder but for this Agreement. XOMA Know-How shall not include the XOMA Patent Rights. All XOMA Know-How shall be confidential information of XOMA.

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

The above definitions are intended 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 the other terms and conditions of this Agreement, XOMA hereby grants to DYAX a worldwide, non-exclusive, non-transferable (other than as provided in Section 9.2) license, without any right to sublicense, under the XOMA Patent Rights and the XOMA Know-How to:

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

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

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

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

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

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(f)                                     on its own behalf and on behalf of a DYAX Development Partner, to make, have made, use, offer for sale, sell and have sold, 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 on behalf of any DYAX Collaborator or Development Partner of DYAX only in respect of or in connection with the activities that such DYAX Collaborator or Development Partner of DYAX is engaged in that are the basis for meeting the definition of DYAX Collaborator or Development Partner of DYAX, as the case may be, and not any other activities, and (ii) without limiting the foregoing, the license granted in Section 2.1(f) is not to be used on behalf of any DYAX Collaborator or any other Third Party that is not a Development Partner of DYAX.

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

2.3           Covenant Not To Sue . In partial consideration for the payments set forth in Sections 4.1 and 4.2, XOMA covenants that it shall not initiate or permit any Third Party over whom it has control to initiate or assist in any way in the initiation or prosecution of any action asserting a claim of infringement under the XOMA Patent Rights or misappropriation of the XOMA Know-How against DYAX, any Development Partner of DYAX or any DYAX Collaborator solely to the extent reasonably necessary to permit the authorized use of Licensed Antibody Phage Display Materials, Licensed Immunoglobulins or Licensed Immunoglobulin Information for activities or in a manner otherwise permitted under the provisions of this Agreement. The parties agree that the covenant not to sue provided by this Section 2.3 (i) is a covenant that transfers with any assignment or sale of, or grant of an exclusive license (with the right to enforce) under, the applicable XOMA Patent Rights by XOMA and (ii) without limiting or expanding the provisions of Section 9.2, shall be binding upon any permitted successors or assigns of XOMA. XOMA agrees to use commercially reasonable efforts to assist DYAX in recording in a form reasonably acceptable to 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 by this Section 2.3:

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

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

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

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

2.4           No Implied Rights . Only the rights and licenses granted pursuant to the express terms of this Agreement shall be of any legal force or effect. No license or other rights shall be deemed to have been granted to DYAX, a Development Partner of DYAX or a DYAX Collaborator other than 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, and expressly exclude, the following:

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

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

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

2.5           Transfer Restrictions .

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

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

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(ii)                                   to further Dispose of Transferred Materials only to a Third Party who otherwise meets the definition of a Development Partner or DYAX Collaborator and who executes a written agreement in which its undertakes all of the obligations applied to the transferring party, provided , however , that this Section 2.5(a)(ii) shall not apply to the Disposition of any Licensed Immunoglobulin where such Third Party is not a Dyax Development Partner and no royalty is or will otherwise be due under Section 4.1;

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

(iv)                               that the covenant not to sue provided by Section 2.3 does not constitute a release or waiver of past, present or future infringement of the XOMA Patent Rights or misappropriation of the XOMA Know-How by such Third Party;

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

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

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

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

(b)           Without expanding or limiting the scope of the licenses and covenants not to sue granted by this Agreement, the provisions of Section 2.5(a) requiring a written agreement prior to any Disposition of any Transferred Materials shall not apply to a transfer of (i) a Licensed Immunoglobulin discovered by Dyax to a Third Party who is not a Dyax Development Partner where the making, selling, offering for sale, importing or exporting of such Licensed Immunoglobulin will occur under conditions which will not give rise to any obligation to pay XOMA any royalties under Section 4.1, or (ii) a Licensed Immunoglobulin discovered exclusively by Dyax to any Third Party where such Disposition is made pursuant to a bona fide material transfer agreement that confers no commercial rights to such Third Party for the sole purpose of permitting such Third Party to evaluate the transferred Licensed Immunoglobulin; provided , howeve r, that upon the execution of any subsequent agreement relating to such Licensed Immunoglobulin, as applicable, the provisions of Section 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 Date of the Original Agreement, DYAX shall deliver to XOMA a written report which shall specify the name, address and contact person for each and every DYAX Collaborator and any person or entity receiving Licensed Antibody Phage Display Materials or a Licensed Immunoglobulin. The reports delivered by DYAX to XOMA pursuant to this Section 2.6(a) shall be Confidential Information of DYAX.

(b)           Not later than thirty (30) days after the end of each calendar year, commencing with the first calendar 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 materials pertaining to the current status of activities or compositions of matter as to which DYAX claims the right of license hereunder.

(c)           DYAX shall maintain records fully and properly reflecting those activities to be reported to XOMA pursuant to Sections 2.6(a) and (b) (the “ Records” ), in sufficient detail and in good scientific manner appropriate for patent, regulatory and manufacturing purposes for at least three (3) years. Upon the written request of XOMA and not more than once in each calendar year, DYAX shall permit an independent consultant appointed by XOMA, at XOMA’s expense, to have access during normal business hours to such of the records of DYAX as may be reasonably necessary to verify compliance with the terms of this Agreement, as well as the accuracy of the reports hereunder. DYAX shall certify any statements by DYAX personnel as to their accuracy and correctness. The consultant shall not be permitted to see or receive any specific information concerning targets or antibodies of either DYAX or any of its collaborators and shall disclose to XOMA only the results and conclusions of its review and the specific details concerning any discrepancies. No other information shall be shared by the consultant without the prior consent of DYAX unless disclosure is required by law, regulation or judicial order.

2.7           Ownership; Enforcement . At all times XOMA will retain ownership of the XOMA Patent Rights and may use and commercialize such XOMA Patent Rights itself or with any Third Party. XOMA retains the right, at its sole discretion, to enforce, maintain and otherwise protect the XOMA Know-How and the XOMA Patent Rights. In addition to the requirements of Section 2.6, DYAX shall give XOMA prompt notice of any infringement of any of the XOMA Patent Rights by a Third Party engaging in a Commercial Antibody Phage Display Business which comes to DYAX’s attention during the term of this Agreement. DYAX will reasonably cooperate with XOMA with respect to any actions XOMA may choose to take related to the enforcement, maintenance or protection of the XOMA Patent Rights.

2.8           Oppositions and/or Appeals to Oppositions . DYAX hereby agrees not to enter into any opposition to and/or appeal from any decision by the patent authorities of any country on the XOMA Patent Rights and shall not assist or otherwise cooperate with another party in any such opposition or appeal.

2.9          Release From Past Infringement . XOMA releases DYAX from any claims, demands, and rights of action arising out of and/or based upon any act or omission committed by 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 those