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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payments, and to revoke our approval of any service provider. You must comply with all our credit-card policies, including minimum purchase requirements for a customer's use of a credit card as prescribed in the Manual. 6.24 Conferences. We may conduct annual conferences or conventions, which may include training sessions. We may require your Operating Principal, Certified Managers, and other designated employees to attend the conferences. You will be solely responsible for all costs incurred by you and your employees in attending any conferences or conventions. 6.25 Pricing. We may, from time to time, but only to the extent permitted by law, establish and impose maximum and minimum prices for the goods and services that you are permitted to sell or offer to sell. If we do so, you must not set your prices below the minimum level that we have established, and not above the maximum level that we have established. 6.26 Certification of Performance. After we perform our preopening obligations under this Agreement, we may request that you execute a certification (the "Certification of Performance"), in a form we reasonably request, confirming such performance. If we make this request, you must execute and deliver the Certification of Performance to us within three-business days of our request. If, however, you do not reasonably believe that we have performed all our preopening obligations under this Agreement, you must, within said three-day period, provide us with written notice specifically describing the obligations that we have not performed. Not later than three-business days after we complete all the obligations specifically described in your notice, you must execute and deliver the Certification of Performance to us. You must do so even if we performed such obligations after the time performance was due under this Agreement. The term "preopening obligations" means such of our obligations to you under this Agreement that must be performed before the Opening Date for the Franchised Business. Page 17 of 39 Source: PF HOSPITALITY GROUP INC., 10-12G, 9/23/2015 7. PROPRIETARY MARKS 7.1. Your Right to Use the Proprietary Marks. Your right to use the Proprietary Marks applies only to the Franchised Business operated from the Premises as expressly provided in this Agreement. During the Term of this Agreement and after its expiration or termination, you agree not to directly or indirectly contest, or aid in contesting, the validity or ownership of the Proprietary Marks or take any action detrimental to our rights in the Proprietary Marks. 7.2. Your Acknowledgments. You acknowledge that: (a) the Proprietary Marks serve to identify our services and the businesses operating under the System; (b) your use of the Proprietary Marks under this Agreement does not give you any ownership interest in them; and (c) all goodwill associated with and identified by the Proprietary Marks inures exclusively to our benefit and is our property. Upon the expiration or termination of this Agreement, no monetary amount will be attributable to goodwill associated with your activities as a franchisee under this Agreement. 7.3. Limitations on Use of the Proprietary Marks. You agree: 7.3.1. To use only the Proprietary Marks we designate, and only in the manner we authorize; 7.3.2. To use the Proprietary Marks only for the operation of the Franchised Business and only at the Premises, or in advertising we have approved for the business conducted at the Premises; 7.3.3. To operate and advertise the Franchised Business only under the name "Pizza Fusion" without prefix or suffix; 7.3.4. To ensure that the Proprietary Marks are used together with the symbol (such as "®", "™", or "SM") that we require from time to time. 7.3.5. To permit us or our representatives to inspect your operations to assure that you are properly using the Proprietary Marks; 7.3.6. To use the Proprietary Marks to promote and to offer for sale only the products and services that we have approved, and not use any Proprietary Marks in association with the products, materials or services of others; 7.3.7. You agree not to use or permit the use or display of the Proprietary Marks as part of any Internet domain name or website, or any other electronic identifier (including but not limited to e-mail addresses, account names in a social media site, and the like) of you or the Franchised Business in any forum or medium; 7.3.8. Not to use the Proprietary Marks to incur any obligation or indebtedness on our behalf; 7.3.9. Not to use any of the Proprietary Marks as part of your corporate or legal name; Page 18 of 39
"""

Extract the exact clause related to "Covenant Not To Sue" from the excerpt above.

assistant: During the Term of this Agreement and after its expiration or termination, you agree not to directly or indirectly contest, or aid in contesting, the validity or ownership of the Proprietary Marks or take any action detrimental to our rights in the Proprietary Marks.