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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inventions, discoveries, methods, specifications, processes, practices, formulae, instructions, skills, techniques, procedures, experiences, ideas, technical assistance, designs, drawings, assembly procedures, computer programs, expertise, technology, other non-clinical, pre-clinical and clinical data, documentation and results (including pharmacological, toxicological, pharmaceutical, biological, chemical, physical, safety and manufacturing data and results), analytical, regulatory and quality control data and results, Regulatory Materials, study designs, protocols, assays, biological methodologies and other technical information, in each case, whether or not confidential, proprietary, patented or patentable. "Know-How" expressly excludes any Patents. 5 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 "Laws" means any law, statute, rule, regulation, standard, order, judgment or ordinance having the effect of law of any applicable national, federal, provincial, state, county, city, or other political subdivision, or foreign, supranational or multinational law, including any statute, standard, code, resolution, or promulgation, or any order, writ, judgment, injunction, decree, stipulation, ruling, determination, or award entered by or with any Governmental Authority, or any license, franchise, permit, or similar right granted under any of the foregoing, or any similar provision having the force or effect of law, including the Federal Food, Drug, and Cosmetic Act (21 U.S.C. § 301, et seq.), the Anti-Kickback Statute (42 U.S.C. § 1320a- 7b), the Civil Monetary Penalty Statute (42 U.S.C. § 1320a-7a), the False Claims Act (31 U.S.C. § 3729 et seq.), comparable state statutes, the regulations promulgated under all such statutes, and the regulations issued by the FDA, and all applicable Anti-Corruption Laws, accounting and recordkeeping laws, and laws relating to interactions with HCPs and Government Officials. For the avoidance of doubt, any specific references to any Law or applicable Law or any portion thereof shall be deemed to include all then-current amendments thereto or any replacement or successor law, statute, standard, ordinance, code, rule, regulation, resolution, promulgation, order, writ, judgment, injunction, decree, stipulation, ruling, or determination thereto. "Losses" has the meaning set forth in Section 9.1. "Manufacture" or "Manufacturing" means all activities related to the manufacturing of a compound or product, including test method development and stability testing, formulation, process development, manufacturing scale-up, manufacturing for use in non-clinical and clinical studies, manufacturing for commercial sale, packaging, release of product, quality assurance/quality control development, quality control testing (including in-process, in-process release and stability testing) and release of product or any component or ingredient thereof, and regulatory activities related to all of the foregoing. "Manufacture" or "Manufacturing" may be included as part of "Develop" or "Development" to the extent applicable, but is expressly exclude from "Commercialize" or "Commercialization". [***] [***] "MMT Indemnitees" has the meaning set forth in Section 9.1. "MMT Promotion Personnel" any employees of MMT or its Affiliates and other approved Third Party contractors, agents and personnel and Permitted Sublicensees, that MMT will assign to conduct Promotion pursuant to this Agreement. "Net Product Sales Amount" means [***] "Non-Compliance Action" has the meaning set forth in Section 8.2(x)(ii). "Non-Promotion Notice" has the meaning set forth in Section 4.2. "Notice of Disagreement" has the meaning set forth in Section 6.5. "Notice of Dispute" has the meaning set forth in Section 12.1(a). 6 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 "Patents" means (a) pending patent applications, issued patents, utility models and design patents anywhere in the world; (b) provisionals, non-provisionals, reissues, substitutions, confirmations, registrations, validations, re-examinations, additions, continuations, continued prosecution applications, continuations-in-part, or divisionals of or to any of the foregoing; (c) any other patent application claiming priority to any of the foregoing anywhere in the world; (d) extension, renewal or restoration of any of the foregoing by existing or future extension, renewal or restoration mechanisms, including supplementary protection certificates or the equivalent thereof; and (e) any foreign equivalents to any of the foregoing. "PDF" means Adobe™ Portable Document Format sent by electronic mail. "Permitted Sublicensee" has the meaning set forth in Section 2.1(b). "Person" means an individual, sole proprietorship, partnership, limited partnership, limited liability partnership, corporation, limited liability company, business trust, joint stock company, trust, incorporated association, joint venture or similar entity or organization, including a government or political subdivision or department or agency of a government or other Governmental Authority. "Pfizer" means Pfizer Inc., a Delaware corporation. "Potential New Field" has the meaning set forth in Section 2.1(c). "Pricing and Reimbursement Authority" means, as applicable, the body with the authority to control, approve, recommend, decide, or otherwise determine pricing and reimbursement of pharmaceutical products, including those with authority to enter into risk sharing schemes or to impose retroactive price reductions, discounts, or rebates (including the National Institute for Health and Care Excellence and the Scottish
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.