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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of Control" means, with respect to either Party, [***]. "Claims" has the meaning set forth in Section 9.1. "Commercialize" means to Promote, distribute, obtain Pricing Approvals and Reimbursement Approvals, import, export and/or conduct other commercialization activities, and "Commercialization" means commercialization activities related to a product, including any and all activities relating to Promoting, distributing, obtaining Pricing Approvals and Reimbursement Approvals, importing and exporting. "Commercialize" or "Commercialization" shall expressly exclude "Develop" or "Development". "Commercially Reasonable Efforts" means, with respect to the efforts to be expended by any Person with respect to any objective, reasonable, diligent and good faith efforts to accomplish such objective. With respect to the Promotion or other exploitation of the Product, "Commercially Reasonable Efforts" means [***]. "Competing Product" means [***]. "Compliance Communications" has the meaning set forth in Section 8.2(x)(i). 2 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 "Confidential Information" of a Party means (a) any and all information of such Party or its Affiliates that is provided or disclosed by such Party or its Affiliates to the other Party or its Affiliates under this Agreement, whether in oral, written, graphic, or electronic form, and (b) the terms of this Agreement. "Control" means, with respect to any material, Know-How, or intellectual property right, that a Party (a) owns or (b) has a license (other than a license granted to such Party under this Agreement) or other right to such material, Know-How, or intellectual property right, and in each case, has the ability to grant to the other Party access, a license, sublicense or other rights (as applicable) to the foregoing on the terms and conditions set forth in this Agreement without violating the terms of any then-existing agreement or other arrangement with any Third Party. "Credit Amount" has the meaning set forth in Section 6.1(b). "Customer" means a Third Party that has entered into a Customer Contract with MMT. "Customer Contract Notice" has the meaning set forth in Section 4.3(b). "Customer Contract" has the meaning set forth in Section 4.3(a). "Delivery Date" shall mean the date set forth in each Purchase Order by which SIGA is to deliver the Product ordered thereunder, which date shall not be any earlier than the corresponding lead time set forth in the applicable Purchase Order. "Develop" or "Development" means any and all activities relating to researching or developing (including synthesizing, screening, testing or evaluating), preparing and conducting non-clinical studies, preparing and conducting clinical studies, and conducting certain regulatory activities (including preparation of regulatory applications) that are necessary or useful to obtain and maintain Regulatory Approval of the Product in any country in the Territory. "Develop" or "Development" may include "Manufacture" or "Manufacturing" but shall expressly exclude "Commercialize" or "Commercialization". "Discontinued Country" has the meaning set forth in Section 4.2. "Dollars" or "$" means U.S. dollars. "EMA" means the European Medicines Agency or any successor entity. [***] "EU" means the economic, scientific and political organization of member states of the European Union as it may be constituted from time to time, which as of the Effective Date consists of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, and the United Kingdom. For clarity, the EU will at all times be deemed to include the United Kingdom, whether or not the United Kingdom remains a member state of the EU. 3 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 "Executive Officers" has the meaning set forth in Section 3.1(e). "Expanded Field" has the meaning set forth in Section 2.1(c). "FD&C Act" means the U.S. Federal Food, Drug, and Cosmetic Act, as amended. "FDA" means the U.S. Food and Drug Administration or any successor entity. "Field" means [***]. "Final Audit Report" has the meaning set forth in Section 6.5. "Final Report" has the meaning set forth in Section 6.2(b). "First Commercial Sale" means the date of the first sale of the Product in the Field in a country in the Territory to a Third Party for monetary value and for end use, including stockpiling, administration, or other consumption of the Product in the Field in such country in the Territory. "GCP" means the then-current standards, practices and procedures promulgated or endorsed by the FDA as set forth in the guidelines entitled "Guidance for Industry E6 Good Clinical Practice: Consolidated Guidance," including related regulatory requirements imposed by the FDA and, as applicable, comparable regulatory standards, practices and procedures promulgated by the EMA or other Regulatory Authority, as
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.