system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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written agreement of the Parties, a provision which will be as similar as possible, in economic and business objectives as intended by the Parties to such invalid, illegal or unenforceable provision, but will be valid, legal and enforceable. 17.3 Waiver. No failure or delay by either Party in exercising any right or remedy under this Agreement will waive any provision of this Agreement. Nor will any single or partial exercise by either Party of any right or remedy under this Agreement preclude it from otherwise or further exercising any rights or remedies which it may have, or any other rights or remedies granted by any law or any related document. 17.4 Enforcement. In the event an action is commenced by either Party against the other to enforce any of the provisions of this Agreement, the prevailing Party shall be entitled to recover from the other Party reasonable attorneys' fees, court costs and necessary disbursements incurred in connection with such action. CERES-IGER Collaboration Agreement Page 27 of 75 17.5 Assignablility. This Agreement binds and enures to the benefit of the Parties, their successor or assigns, but may not be assigned by either Party without the prior written consent of the other Party; provided however, CERES shall have the right to assign its rights and obligations under this Agreement to any Affiliated Company without such prior consent. Each Party shall have the right to assign its rights and obligations under this Agreement to a third party in conjunction with the transfer to such third party of substantially all of the assets of such Party associated with performance under this Agreement without such prior consent. "Affiliated Company" defined as any company owned or controlled by, under common control with or controlling CERES, "control" meaning in this context the direct or indirect ownership of fifty percent (50%) or more of the voting stock/shares of a company, or the power to nominate at least half of the directors. 17.6 Force Majeure. No Party shall be responsible to the other Party for delay or failure in performance of any the obligations imposed by this Agreement, provided such failure shall be occasioned by fire, flood, explosion, lightning, wind storm, hailstorm, earthquake, subsidence of soil, failure of machinery or equipment or supply of materials, discontinuity in the supply of power, court order or governmental interference, terrorist attacks, civil commotion, riot, war, strikes, labor disturbances, transportation difficulties, labor shortage, natural genetic variation of any living matter or by any other cause of like or unlike nature beyond the reasonable control and without fault or negligence of such Party. 18. SPECIAL CONDITIONS IN CONNECTION WITH DEFRA AGREEMENT NF 0426. The Parties acknowledge that Defra is expected to assign or license exclusively to IGER any rights in Intellectual Property which would vest in Defra or the Crown or the Secretary of State pursuant to the DEFRA agreement NF 0426. If IGER receives an exclusive license from Defra rather than an assignment of rights, the following will apply. 18.1 To the extent the license grant to CERES on IGER BACKGROUND INTELLECTUAL PROPERTY in Article 5.3.2 relates to IGER BACKGROUND INTELLECTUAL PROPERTY that constitutes Intellectual Property to which rights vest in Defra or the Crown or the Secretary of State, the word "license" will be read as "sublicense" and all other terms of such Article will remain unchanged. 18.2 To the extent that IGER INTELLECTUAL PROPERTY or JOINT INTELLECTUAL PROPERTY created in a RESEARCH PROJECT constitutes or includes Intellectual Property to which rights vest in Defra or the Crown or the Secretary of State, any conveyance or grant of rights or licenses by IGER to CERES in this Agreement with respect to such IGER INTELLECTUAL PROPERTY or JOINT INTELLECTUAL PROPERTY, will be read as the grant of an exclusive sublicense under IGER's exclusive license from Defra. CERES-IGER Collaboration Agreement Page 28 of 75 IN WITNESS WHEREOF, IGER and CERES have caused this Agreement to be duly executed as indicated below. INSTITUTE OF GRASSLAND AND ENVIRONMENTAL RESEARCH CERES, INC. By: /s/ MERVYN HUMPHREYS By: /s/ RICHARD FLAVELL Name: Professor Mervyn Humphreys Name: Richard Flavell, CBE, FRS Title: Director Title: Chief Scientific Officer By: /s/ RICHARD HAMILTON Name: Richard Hamilton Title: President and Chief Executive Officer CERES-IGER Collaboration Agreement Page 29 of 75 EXHIBIT A to the Collaboration Agreement between IGER and CERES DEFINITION OF COLLABORATION CROPS Miscanthus and interbreeding species, including without limitation Saccharum and Erianthus species. CERES-IGER Collaboration Agreement Page 30 of 75 EXHIBIT B to the Collaboration Agreement between IGER and CERES
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Extract the exact clause related to "Exclusivity" from the excerpt above.

assistant: If IGER receives an exclusive license from Defra rather than an assignment of rights, the following will apply. 18.1 To the extent the license grant to CERES on IGER BACKGROUND INTELLECTUAL PROPERTY in Article 5.3.2 relates to IGER BACKGROUND INTELLECTUAL PROPERTY that constitutes Intellectual Property to which rights vest in Defra or the Crown or the Secretary of State, the word "license" will be read as "sublicense" and all other terms of such Article will remain unchanged. 18.2 To the extent that IGER INTELLECTUAL PROPERTY or JOINT INTELLECTUAL PROPERTY created in a RESEARCH PROJECT constitutes or includes Intellectual Property to which rights vest in Defra or the Crown or the Secretary of State, any conveyance or grant of rights or licenses by IGER to CERES in this Agreement with respect to such IGER INTELLECTUAL PROPERTY or JOINT INTELLECTUAL PROPERTY, will be read as the grant of an exclusive sublicense under IGER's exclusive license from Defra.