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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works of authorship including copyrights, copyright applications, and copyright registrations; (c) rights relating to the protection of trade secrets, know-how or confidential information; and (d) rights in any trade names, trademarks, service marks, domain names, logos, trade dress and brand features. 1.15. Net Revenue is defined on Exhibit A. 1.16. Patent Rights means all patents, patent applications and inventions on which patent applications are filed and all patents issuing therefrom worldwide, together with any extensions, registrations, confirmations, reissues, continuations, divisionals, continuations- in-part, re-examination certificates, substitutions or renewals, supplemental protection certificates, term extensions (under applicable patent law or other law), provisional rights and certificates of inventions. 1.17. Potentially Serious Complaint shall mean any information coming to the notice of Qualigen or Sekisui which might relate to a Serious Incident (as hereinafter defined), or to a significant lapse in the quality of the Products, or might lead to significant adverse public or media comment, or otherwise significantly, adversely affect the reputation or business of Sekisui or Qualigen. 1.18. Products shall mean all of Qualigen's current and future products, including without limitation those listed on Exhibit D, for sale under the trade names listed with such products, including any improvements thereto. 1.19. Qualigen Retained Customers shall mean certain of Qualigen's existing direct sales customers, all as listed on Exhibit E. 1.20. Regulatory Approval shall mean the approval of the applicable Regulatory Authority required for the promotion, marketing, distribution and/or sale of the Products in any territory in which they are being sold, including any Product registration or license, and any supplement, amendment or variation thereto, required before the commencement of commercial sales of the Products in such territory, and export and import approvals for the Products. 2 Source: RITTER PHARMACEUTICALS INC, S-4/A, 3/13/2020 1.21. Regulatory Authorities shall mean the FDA, each Competent Authority, Health Canada and the Japanese Pharmaceuticals and Medical Devices Agency. 1.22. Revenue Affiliate shall mean any entity of which Sekisui has the direct or indirect power to vote more than fifty percent (50%) of the outstanding voting securities (or other ownership interest for a business organization other than a corporation) of that entity, or the direct or indirect ability to direct or cause the direction of the general management and policies of that entity. 1.23. Sale Transaction shall mean (i) any transaction in which Qualigen, Qualigen's business or control of Qualigen is acquired, (ii) any license, sale, lease, transfer, or other disposition, in a single transaction or series of related transactions, of all or substantially all of Qualigen's assets other than in the ordinary course of business, (iii) any sale of a majority of the outstanding shares of capital stock of Qualigen, (iv) any sale or license of any rights to any Qualigen products, now or hereafter existing, other than in the ordinary course of business, (v) any liquidation or dissolution of Qualigen, (vi) any similar transaction resulting in a change of control of Qualigen, or (vii) any of the foregoing with respect to any now or hereafter existing subsidiary of Qualigen which holds, on a consolidated basis, all or substantially all of Qualigen's assets (i.e., of the assets of Qualigen and all its Affiliates considered together). 1.24. Serious Incident shall mean an incident involving the Products, which is reportable to a Competent Authority and as defined in Section 5 of Annex III of the IVD Directive, and the European Commission Medical Devices Vigilance Guidelines 2.12-1 or such other Guidelines as may be issued from time to time. 1.25. Territory shall mean worldwide excluding Qualigen Retained Customers. 1.26. Third Party shall mean a party other than Sekisui or Qualigen or any Affiliate of Sekisui or Qualigen. 2. Appointment and Term 2.1. Appointment. Qualigen hereby appoints Sekisui, and Sekisui accepts the appointment to act on an exclusive basis pursuant to the terms and conditions of this Agreement, as a distributor for the sale of the Products in the Territory. Sekisui shall be permitted to appoint sub-distributors in the Territory (including any current Qualigen distributors) with the approval of Qualigen, not to be unreasonably withheld or delayed. Sekisui shall purchase the Products exclusively from Qualigen, and Qualigen shall supply the Products exclusively to Sekisui, in each case for the Territory. Qualigen shall assign to Sekisui Qualigen's agreements with Qualigen's current distributors (such that such current Qualigen distributors shall become Sekisui subdistributors), each of which is set forth on Schedule 2.1 hereto; if any of such agreements do not allow such assignment and the current distributor declines to consent to such an assignment
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.