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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for their own use are NOT in violation of this Agreement. 14. Trademarks All Chase trademarks, trade names and service marks (collectively, the "Marks") are the exclusive property of Chase. Notwithstanding anything set forth in this Agreement, Chase reserves full ownership of the Marks and the Licensed Materials (as defined below). All use of the Marks by Affiliate is limited solely to the use contemplated by this Agreement. All use of Chase Marks by Affiliate is subject to the prior written approval of Chase. 15. Licenses and Use of the Chase Logos and Trademarks Chase grants Affiliate a non-exclusive, nontransferable, revocable right to (a) access the Chase site through the links solely in accordance with the terms of this Agreement and (b) solely in connection with such links, to use Chase's logos, trade names, trademarks, and similar identifying material relating to Chase (collectively, the "Licensed Materials"), for the sole purpose of booking Chase products. Prior to using any of the Licensed Materials, Affiliate will submit to Chase for approval a draft of all proposed material that incorporates the Licensed Materials, together with a brief statement setting forth the proposed use of such materials and any other background or supporting material reasonably requested by Chase to allow Chase to make an informed judgment. All such materials shall be submitted to Chase at least seven (7) days prior to the date of first intended use. Chase will notify Affiliate of its approval or disapproval of such materials within five (5) business days of its receipt of all information required to be submitted. The approval or disapproval of such materials will be in Chase's sole discretion. Any materials not receiving Chase's specific written preliminary approval will be deemed disapproved. Affiliate may not alter, modify, or change the Licensed Materials in any way. Affiliate is only entitled to use the licensed materials to the extent that it is a member in good standing of the Chase Affiliate Program. Affiliate agrees not to use the Licensed Materials in any manner that is disparaging or that otherwise portrays Chase in a negative light. Chase may revoke Affiliate's license at any time. 16. Service Interruption Certain technical difficulties may, from time to time, result in service interruptions. Affiliate agrees not to hold Chase responsible for the consequences of such interruptions. 17. Indemnification Source: CREDITCARDS.COM, INC., S-1, 8/10/2007 Affiliate hereby agrees to indemnify, defend, and hold harmless Chase, its shareholders, officers, directors, employees, agents, affiliates and their respective directors, officers, employees and agents, successors and assigns, from and against any and all claims, demands, losses, liabilities, damages or expenses (including attorneys' fees and costs) of any nature whatsoever incurred or suffered by Chase (collectively the "losses"), in so far as such losses (or actions in respect thereof) arise out of, are related to, or are based on (i) the breach of any representation, warranty, or covenant made by Affiliate herein; or (ii) any claim related to Affiliate's site. 18. Confidentiality Except as otherwise provided in this Agreement or with the consent of the other party hereto, each of the parties hereto agrees that all information including, without limitation, the terms of this Agreement, business and financial information, customer and vendor lists, and pricing and sales information, concerning Chase, Customer or Affiliate shall remain strictly confidential and secret and shall not be utilized, directly or indirectly, by such party for its own business purposes or for any other purpose except and solely to the extent necessary to exercise rights and perform obligations under this Agreement. The foregoing restrictions will not apply to information to the extent it (i) was known to the receiving party at the time of disclosure; (ii) has become publicly known through no wrongful act of the receiving party; (iii) has been rightfully received from a third party under no obligation to the disclosing party; (iv) has been disclosed by court order or as otherwise required by law if the receiving party has given the disclosing party a reasonable opportunity to contest or limit the scope of such required disclosure. 19. Modification Chase reserves the right to change any and all of the terms and conditions in this Agreement, at any time and in its sole discretion, by posting a new agreement on its Website. Without limiting the generality of the foregoing, the amount of Commissions, the definition of Approved Accounts, and all other provisions of this Agreement are subject to change without notice other than posting such information on the Chase Website. IF ANY MODIFICATION
"""

Extract the exact clause related to "Most Favored Nation" from the excerpt above.

assistant: Not found.