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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paying the Gross Receipts Tax, equals the net amount of the payments you are required to pay us or the Entity had such Gross Receipts Tax not been imposed. You are not required to pay income taxes payable by us or any Entity as a result of our net income relating to fees collected under this Agreement. 8.5 Application of Fees. We may apply any amounts received from you to any amounts due under this Agreement. 9.0 PROPRIETARY RIGHTS 9.1 Our Proprietary Rights. 9.1.1 You will not contest, either directly or indirectly during or after the Term: 9.1.1.1 our (and/or any Entities') ownership of, rights to and interest in the System, Brand, Marks and any of their elements or components, including present and future distinguishing characteristics and agree that neither you nor any design or construction professional engaged by you may use our Standards, our Manual or your approved Plans and Designs for any hotel or lodging project other than the Hotel; 9.1.1.2 our sole right to grant licenses to use all or any elements or components of the System; 9.1.1.3 that we (and/or the Entities) are the owner of (or the licensee of, with the right to sub-license) all right, title and interest in and to the Brand and the Marks used in any form and in any design, alone or in any combination, together with the goodwill they symbolize; or 9,1.1.4 the validity or ownership of the Marks. 9.1.2 You acknowledge that these Marks have acquired a secondary meaning which indicates that the Hotel, Brand and System are operated by or with our approval. All improvements and additions to, or associated with, the System, all Marks, and all goodwill arising from your use of the System and the Marks, will inure to our benefit and become our property (or that of the applicable Entities), even if you develop them. 9.1.3 You will not apply for or obtain any trademark or service mark registration of any of the Marks or any confusingly similar marks in your name or on behalf of or for the benefit of anyone else. You acknowledge that you are not entitled to receive any payment or other value from us or from any of the Entities for any goodwill associated with your use of the System or the Marks, or any elements or components of the System. 9.2 Trade Name, Use of the Marks. 9,2.1 Trade Name. 9.2.1.1 The Hotel will be initially known by the Trade Name set forth in the Addendum. We may change the Trade Name, the Brand name and/or any of the Marks (but not the Principal Mark), or the way in which any of them (including the Principal Mark) are depicted, at any time at our sole option and at your expense. You may not change the Trade Name without our specific prior written consent. 15 9.2.1.2 You acknowledge and agree that you are not acquiring the right to use any service marks, copyrights, trademarks, trade dress, logos, designs, insignia, emblems, symbols, slogans, distinguishing characteristics, trade names, domain names or other marks or characteristics owned by us or licensed to us that we do not specifically designate to be used in the System. 9.3 Use of Trade Name and Marks. You will operate under the Marks, using the Trade Name, at the Hotel. You will not adopt any other names or marks in operating the Hotel without our approval. You will not, without our prior written consent, use any of the Marks, or the word "Hilton," or other Network trademarks, trade names or service marks, or any similar words or acronyms, in: 9.3.1 your corporate, partnership, business or trade name; 9.3.2 any Internet-related name (including a domain name); 9.3.3 or any business operated separately from the Hotel, including the name or identity of developments adjacent to or associated with the Hotel. 9.4 Trademark Disputes. 9.4.1 You will immediately notify us of any infringement or dilution of or challenge to your use of any of the Marks and will not, absent a court order or our prior written consent, communicate with any other person regarding any such infringement, dilution, challenge or claim. We will take the action we deem appropriate with respect to such challenges and claims and have the sole right to handle disputes concerning use of all or any part of the Marks or the System. You will fully cooperate with us and any applicable Entity in these matters. We will reimburse you for expenses incurred by you as
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Extract the exact clause related to "Covenant Not To Sue" from the excerpt above.

assistant: You will not contest, either directly or indirectly during or after the Term: 9.1.1.1 our (and/or any Entities') ownership of, rights to and interest in the System, Brand, Marks and any of their elements or components, including present and future distinguishing characteristics and agree that neither you nor any design or construction professional engaged by you may use our Standards, our Manual or your approved Plans and Designs for any hotel or lodging project other than the Hotel; 9.1.1.2 our sole right to grant licenses to use all or any elements or components of the System; 9.1.1.3 that we (and/or the Entities) are the owner of (or the licensee of, with the right to sub-license) all right, title and interest in and to the Brand and the Marks used in any form and in any design, alone or in any combination, together with the goodwill they symbolize; or 9,1.1.4 the validity or ownership of the Marks.