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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EXHIBIT 10.1 ENDORSEMENT AGREEMENT This Endorsement Agreement ("Agreement") made October 30, 2017, between National Football League Alumni - Northern California Chapter ("NFLA-NC"), a charitable corporation organized under the laws of California, having its principal office at 1311 Madison Avenue, Redwood CA 94061; National Football League Alumni, Inc. ("NFLA"), a charitable corporation organized under the laws of Florida, having its principal office at 8000 Midlantic Drive, 130 S., Mount Laurel, NJ. 08054 and Food For Athletes, Inc. a corporation organized under the laws of California / Gridiron BioNutrients™, a corporation organized under the laws of Nevada having their principal office(s) at 1119 West 1st Ave., STE G, Spokane, WA 99201 (collectively the "Company"). RECITALS A. Whereas, NFLA is a nationwide group of former National Football League players, coaches, and other employees whose mission is to serve, assist and inform players and their families. The association offers a variety of medical, financial and social programs to help members lead healthy, productive and connected lives. B. Whereas, NFLA-NC is a local Chapter of the NFLA and supports the organizations "Caring for Kids" initiative through fundraising for youth-related charities. C. The Company desires to obtain the rights to use the Pro Football Legends Logo of the NFLA in connection with the advertisement and promotion of certain of its products. An image of the Pro Football Legends Logo is depicted in Exhibit A. D. The NFLA agrees to license such rights to the Company. In consideration of the matters described above, and of the mutual benefits and obligations set forth in this Agreement, the parties agree as follows: SECTION ONE. DEFINITIONS As used in this Agreement, the following terms shall be defined as follows: A. "Contract Period" shall mean that period of time of three (3) years commencing on November 1st, 2017 and concluding November 2nd, 2020, unless terminated sooner or extended as provided in this Agreement. B. "Contract Territory" shall mean worldwide. C. "Contract Year" shall mean each of the consecutive 12-month periods beginning on the effective date of the Agreement of the Contract Period. 1 Source: GRIDIRON BIONUTRIENTS, INC., 8-K, 12/6/2017 D. "Gross Sales" shall mean total revenues, under generally accepted accounting principles, from sales of the Licensed Products, but does not include any revenue from sales, use or other transaction taxes, duties, handling, graphics, embroidery or shipping. E. "Net Sales" shall mean Gross Sales less Product returns, trade discounts, samples, allowances, value added services, markdowns, customer charge backs and liquidation sales (substantially discounted and out of ordinary distribution channel) of Licensed Products. F. "Licensed Products" shall mean BlackMP Living Water, BlackMP Concentrate, Zezel Probiotic Water, Zayin Sports Water, Gridiron MVP™ and Gridiron MVP™ Concentrate using the Pro Football Legends Logo on the Licensed Products' affixed labels, hang-tags or packaging. Other products of the Company may be added to the list of Licensed Products during the Contract Period by written amendment to this Agreement. All amendments to this Agreement must be signed by all parties to this Agreement. G. "Products" shall mean goods manufactured, distributed or otherwise sold by the Company. H. "Licensed Marks" shall mean in connection with the rights and benefits granted to Company hereunder as set forth in General Terms. Company may utilize only the logo and other trademarks listed on Exhibit A (the "Licensed Marks") during the Term and within the Territory solely in connection with advertising and promotional materials that identify Company as a sponsor of the Pro Football Legends, provided that NFLA first approves all such uses in writing. Any use of the Licensed Marks will bear the trademark and/or copyright notices required by NFLA to facilitate its trademark protection program and will be a "work made for hire" for NFLA. All of Company's uses of the Licensed Marks shall inure to the benefit of the NFLA. After the expiration or termination of this Agreement, Company will refrain from further use of the Licensed Marks used pursuant to this Agreement. Company will not sublicense pass-through or otherwise grant to any third parties the rights granted to Company hereunder without the NFLA prior written consent, including but not limited to the right to use the Licensed Marks. Company acknowledges that this Agreement does not grant Company any rights with respect to any other NFLA Marks (defined below), the name, likeness, signature, or other attributes of any NFLA member or other individual, or any audio or video of any NFLA event. Company agrees that the quality of all services offered by Company under the Licensed Marks will conform to
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Extract the exact clause related to "Covenant Not To Sue" from the excerpt above.