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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the following (collectively referred to herein as the "Restricted Party Lists"): the list of sanctioned entities maintained by the UN; the Specially Designated Nationals List and the Sectoral Sanctions Identifications List, as administered by the U.S. Department of the Treasury Office of Foreign Assets Control; the U.S. Denied Persons List, the U.S. Entity List, and the U.S. Unverified List, all administered by the U.S. Department of Commerce; the entities subject to restrictive measures and the Consolidated List of Persons, Groups and Entities Subject to E.U. Financial Sanctions, as implemented by the E.U. Common Foreign & Security Policy; the List of Excluded Individuals / Entities, as published by the U.S. Health and Human Services - Office of Inspector General; any lists of prohibited or debarred parties established under the U.S. Federal Food Drug and Cosmetic Act; the list of Persons and entities suspended or debarred from contracting with the U.S. government; and similar lists of restricted parties maintained by the Governmental Authorities of the countries that have jurisdiction over the activities conducted under this Agreement. 8 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 "Restricted Party Lists" has the meaning set forth in the definition of Restricted Party. [***] [***] [***] "Rolling Forecast" has the meaning set forth in Section 5.1(a). "SEC" has the meaning set forth in Section 10.4(d). "Sell or Offer to Sell" means actual negotiation of terms of purchase and contracting for sale of Product in the Field in the Territory. "Selling Party" has the meaning set forth in the definition of Net Product Sales Amounts. "SIGA Indemnitees" has the meaning set forth in Section 9.2. "SIGA Intellectual Property" means the SIGA Know-How, SIGA Trademarks, SIGA Patents and SIGA Inventions. "SIGA Know-How" means all Know-How that (a) is necessary or useful for the Development, Manufacture or Commercialization of the Product in the Field in the Territory and (b) (i) is Controlled by SIGA or its Affiliates as of the Effective Date or (ii) is or becomes Controlled by SIGA or its Affiliates during the Term. "SIGA Patent" means any Patent that (a) claims, generically or specifically, the Product, or the Manufacture or use of the Product in the Field (including its intermediates and relevant compounds) and (b)(i) is Controlled by SIGA or its Affiliates as of the Effective Date, which such Patents are set forth in Schedule 1 hereto, (ii) is Controlled by SIGA or its Affiliates during the Term and claims priority to the Patents Controlled by SIGA or its Affiliates as of the Effective Date, or (iii) is or becomes Controlled by SIGA or its Affiliates during the Term. "SIGA Trademark" means any Trademark that (a) is necessary for the Development, Manufacture or Commercialization of a Product in the Field in the Territory and (b) (i) is Controlled by SIGA or its Affiliates as of the Effective Date (which such Trademarks are set forth in Schedule 2 hereto) or (ii) is or becomes Controlled by SIGA or its Affiliates during the Term. 9 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 "SIGA's Auditor" has the meaning set forth in Section 6.5. "South Korea" means South Korea, including all of its territories and possessions. "Special Access Approval" has the meaning set forth in Section 4.4(b). "Supply Limitation" has the meaning set forth in Section 5.4. "Supply Terms" means [***]. "Term" has the meaning set forth in Section 11.1. "Territory" means all countries and territories in the world other than (a) the U.S., (b) South Korea, (c) any Restricted Market, and (d) any Discontinued Country and, in the case of (a)-(c), each of their respective territories and possessions. "Third Party" means any Person other than SIGA or MMT or an Affiliate of either of them. "Tier 1 Countries" mean [***]. "Tier 2 Countries" mean [***]. "Tier 3 Countries" mean [***]. "Tier Period" has the meaning set forth in Section 4.2. "Trademark" means any trademark, service mark, trade name, brand name, sub-brand name, trade dress, product configuration, program name, product name, delivery form name, certification mark, collective mark, logo, tagline, slogan, design or business symbol, that functions as an identifier of source or origin, whether or not registered and all statutory and common law rights therein and all registrations and applications therefor, together with all goodwill associated with, or symbolized by, any of the foregoing. "U.S." means the United States of America, including all of its territories and possessions. "VAT" has the meaning set forth in Section 6.8(c). "Yearly Collected Revenue" means Net Product Sales Amount that is collected during the applicable Calendar
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.