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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later than sixty (60) days before the end of each fiscal year, a budget and business plan for the next fiscal year, prepared on a monthly basis, including balance sheets and income statements. 8. Intellectual Property Rights 8.1. Background Intellectual Property Rights. Each Party shall own and retain all right, title and interest in and to all of its Intellectual Property Rights created before or independently from the Development Plan and this Agreement ("Qualigen Background IP" and "Sekisui Background IP," respectively). 8.2. Development Plan Intellectual Property Rights. Except as set forth in this Section, Qualigen shall own all right, title and interest in and to all Intellectual Property Rights (if any) resulting from Qualigen's activities under the Development Plan ("Development IP"), but excluding all Sekisui Background IP. In the event that any Development IP is jointly invented by the Parties in accordance with applicable intellectual property laws, then the ownership of such Development IP that has been jointly invented shall be co-owned by the Parties in accordance with such applicable intellectual property laws; provided, however, that neither Party shall have any duty or obligation to account to the other for any use or exploitation of such jointly invented Development IP and as between the Parties, each Party shall be entitled to retain any and all benefit, financial or otherwise, derived by such Party from such jointly invented Development IP. 8.3. Prosecution and Enforcement of Development IP. Except as set forth below, Qualigen shall have the sole right to prepare, file applications on and registrations for, prosecute, obtain, maintain, defend and enforce all Intellectual Property Rights in the Development IP in such manner as Qualigen deems appropriate in its sole discretion, including incurring and paying all expenses required for such purposes. Notwithstanding the foregoing, Qualigen shall use commercially reasonable efforts to preserve, obtain and maintain in the Applicable Markets all material Development IP and Qualigen Background IP related to or used in connection with the development and manufacturing of the Products as well as any improvements or alternative embodiments thereof, and shall consult Sekisui before determining not to pursue in any Applicable Market any particular Intellectual Property Rights related to any product development efforts covered by the Development Plan. In the event that Qualigen elects not to prosecute or maintain in a particular Applicable Market country any Patent Rights in the jointly developed Development IP (the "Abandoned Joint IP"), Sekisui may elect to prosecute such Abandoned Joint IP in such particular Applicable Market country, in which case the Patent Rights for such Abandoned Joint IP in such particular in Applicable Market country shall be owned solely by Sekisui. 12 Source: RITTER PHARMACEUTICALS INC, S-4/A, 3/13/2020 8.4. Marks. During and after the Term, neither Party shall register, use or claim ownership or other rights in any logo, trade name, brand name or trademark of the other Party in existence during the Term (nor any logo, trade name, brand name or trademark confusingly similar to any logo, trade name, brand name or trademark of the other Party in existence during the Term), nor assist anyone else to do so, nor make or assist in any challenge to any logo, trade name, brand name or trademark of the other Party in existence during the Term. 9. Sale Transaction 9.1. Exclusivity Period. The parties anticipate that they will entertain a potential acquisition of Qualigen by Sekisui during 2018 on terms to be mutually agreed. Accordingly, Qualigen hereby agrees that during the Exclusivity Period, Qualigen shall not, directly or indirectly, through its affiliates, agents, stockholders, officers, directors or otherwise solicit, initiate, participate in discussions or negotiations or otherwise cooperate in any way with, or provide any information to any person, entity or group other than Sekisui concerning a Sale Transaction. In the event that Qualigen nonetheless receives an unsolicited offer to engage in a Sale Transaction during such Exclusivity Period, Qualigen may engage with such party to the extent legally required to comply with its fiduciary duties, so long as Qualigen (i) promptly communicates to Sekisui the material terms of any proposal or offer or request for information which it may receive in respect of any such proposed Sale Transaction, including the purchase price, form and timing of consideration and the identity of the acquirer, and (ii) complies with Sekisui's Right of First Refusal (as defined below). 9.2. Negotiation Period. No later than July 1, 2018 (and sooner upon Sekisui's written request at any time before July 1, 2018), the parties shall engage in good faith
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.