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 European Union, as its membership may be altered from time to time, and any successor thereto. 1.59 "Existing Patents" has the meaning set forth in Section 10.2.1. 1.60 "Exploit," "Exploited" or "Exploitation" means to make, have made, import, export, use, sell, or offer for sale, including to Develop, Commercialize, register, modify, enhance, improve, Manufacture, have Manufactured, hold, or keep (whether for disposal or otherwise), formulate, optimize, have used, export, transport, distribute, promote, market, have sold or otherwise dispose of. 1.61 "FDA" means the United States Food and Drug Administration and any successor agency(ies) or authority having substantially the same function. 1.62 "FFDCA" means the United States Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 301 et seq., as amended from time to time, together with any rules, regulations and requirements promulgated thereunder (including all additions, supplements, extensions, and modifications thereto). 1.63 "Field" means all human and non-human diagnostic, prophylactic, and therapeutic uses. 1.64 "Final Development Report" means the final written data package delivered by Harpoon to AbbVie in accordance with Section 3.1.3, after the completion of all activities under the Initial Development Plan, including, for clarity, [***], and comprised of the [***]. The Final Development Report shall include [***]. - 7 - Source: HARPOON THERAPEUTICS, INC., 10-K, 3/12/2020 1.65 "First Commercial Sale" means, with respect to a Licensed Product and a country, the first sale for monetary value for use or consumption by the end user of such Licensed Product in such country after Regulatory Approval for such Licensed Product has been obtained in such country. [***] shall not be construed as a First Commercial Sale. 1.66 "Harpoon" has the meaning set forth in the preamble hereto. 1.67 "Harpoon In-License Agreement" means [***] agreement between Harpoon and a Third Party under which AbbVie is granted a sublicense or other right under this Agreement as provided in Section 5.9. 1.68 "Harpoon Indemnitees" has the meaning set forth in Section 11.1. 1.69 "Harpoon Know-How" means all Information that is (a) Controlled by Harpoon or any of its Affiliates as of the Effective Date or at any time during the Term, (b) not generally known and (c) necessary or reasonably useful for the Exploitation of any Licensed Compound or any Licensed Product, but excluding any Joint Know-How or Information published in any (i) Harpoon Patents or (ii) Joint Patents. 1.70 "Harpoon Patents" means all of the Patents that are (a) Controlled by Harpoon or any of its Affiliates as of the Effective Date or at any time during the Term and (b) necessary or reasonably useful (or, with respect to Patent applications, would be necessary or reasonably useful if such Patent applications were to issue as Patents) for the Exploitation of any Licensed Compound or any Licensed Product, but excluding Joint Patents. The Harpoon Patents include the Existing Patents. 1.71 [***] has the meaning set forth in [***]. 1.72 "Harpoon Reversion Products" has the meaning set forth in Section 12.6.1. 1.73 "HSR Act" means the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended. 1.74 "HSR Filing" has the meaning set forth in Section 3.2.4(b). 1.75 "In-Licensed Patents" has the meaning set forth in Section 10.2.3. 1.76 "IND" means an application filed with a Regulatory Authority for authorization to commence Clinical Studies, including (a) an Investigational New Drug Application as defined in the FFDCA or any successor application or procedure filed with the FDA, (b) any equivalent thereof in other countries or regulatory jurisdictions, (e.g., a Clinical Trial Application (CTA) in the European Union) and (c) all supplements, amendments, variations, extensions and renewals thereof that may be filed with respect to the foregoing. 1.77 "Indemnification Claim Notice" has the meaning set forth in Section 11.3. 1.78 "Indemnified Party" has the meaning set forth in Section 11.3. 1.79 "Indication" means, with respect to a Licensed Product, a use to which such Licensed Product is intended to be put for the treatment, prevention, mitigation, cure or diagnosis of a recognized disease - 8 - Source: HARPOON THERAPEUTICS, INC., 10-K, 3/12/2020 or condition, or of a manifestation of a recognized disease or condition, or for the relief of symptoms associated with a recognized disease or condition, in each case for any size patient population, which, if such Licensed Product is approved in the U.S., would be reflected in the "Indications and Usage" section of labeling pursuant to 21 C.F.R. §201.57(c)(2) or, to the extent applicable, any comparable labeling section outside the U.S., subject to the following: (a) subtypes of the same disease or condition are
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.