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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the other party's Trademarks that a party intends to use shall be exact copies of those used by the other party and shall first be submitted to the originating party for approval of design, color and other details, which consent shall not be unreasonably withheld or delayed. To ensure trademark quality, each party shall fully comply with all written guidelines provided by the other party concerning the use of the originating party's Trademarks. Each party agrees to change or correct any material or activity that the originating party determines to be inaccurate, objectionable, misleading or a misuse of the originating party's Trademarks. [*] Certain information on this page has been omitted and filed separately with the Commission. Confidential treatment has been requested with respect to the omitted portions. 7 8 7 WARRANTIES AND DISCLAIMER. 7.1 No Conflict. Each party represents and warrants to the other party that it is under no current obligation or restriction, nor will it knowingly assume any such obligation or restriction that does or would in any way interfere or conflict with, or that does or would present a conflict of interest concerning the performance to be rendered hereunder or the rights and licenses granted herein. 7.2 Intellectual Property Warranty. Commerce One represents and warrants to Corio that (a) Commerce One is the sole and exclusive owner of the Software; (b) Commerce One has full and sufficient right, title and authority to grant the rights and/or licenses granted to Corio under this Agreement; (c) the Software does not contain any materials developed by a third party used by Commerce One except pursuant to a license agreement; and (d) the Software does not infringe any patent, copyright, trade secret, trademark or other intellectual property rights of a third party. 7.3 Product Warranty. Commerce One warrants that the Software and MarketSite.net Service will perform in substantial accordance with the Documentation, and the media on which the Software is distributed will be free from defects in materials and workmanship under normal use, for a period of sixty (60) days from the Effective Date, but in no event not later than December 31, 1999 (the "Warranty Period"). In addition, Commerce One warrants that during the Warranty Period the Software and MarketSite.net Service is free of any willfully introduced computer virus, or any other similar harmful, malicious or hidden program or data, which is designed to disable, erase, or alter the Software, or any other files, data, or software. If during the Warranty Period the Software and MarketSite.net Service does not perform in substantial compliance with the Documentation, Commerce One shall take all commercially reasonable efforts to correct the Software and MarketSite.net Service, or if correction of the Software and MarketSite.net Service is reasonably not possible, replace such Software and MarketSite.net Service free of charge. Commerce One will replace any defective media returned to Commerce One during the Warranty Period. In the event any such breach of warranty can not be reasonably corrected at Commerce One's sole expense, Corio has the right to terminate this Agreement and receive a refund of all prepaid fees. The foregoing are Corio's sole and exclusive remedies for breach of product warranty. The warranty set forth above is made to and for the benefit of Corio only. The warranty shall not apply only if: (a) the Software and MarketSite.net Service has been not properly installed and used at all times and in accordance with the Documentation; and (b) Corio has requested modifications, alterations or additions to the Software and MarketSite.net Service that cause it to deviate from the Documentation. 7.4 Product Warranty - Year 2000 Compliance. Commerce One warrants that the Software and MarketSite.net Service, when used in accordance with its associated documentation, is in all material respects capable upon installation of accurately processing, providing and/or receiving date data from, into and between the twentieth and twenty-first centuries, including the years 1999 and 2000, and leap year calculations; provided that all licensee and third party equipment, systems, hardware, software and firmware used in combination with the Software and MarketSite.net Service properly exchange date data with the Software and MarketSite.net Service 8 9 OTHERWISE, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A PARTICULAR PURPOSE. 8 INDEMNIFICATION. 8.1 By Commerce One. Commerce One shall indemnify, defend and hold harmless Corio and its Customers from any and all damages, liabilities, costs and expenses (including reasonable attorneys' fees) incurred by Corio or its Customers arising out of any claim that the Software infringes any patent,
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Extract the exact clause related to "Warranty Duration" from the excerpt above.

assistant: In addition, Commerce One warrants that during the Warranty Period the Software and MarketSite.net Service is free of any willfully introduced computer virus, or any other similar harmful, malicious or hidden program or data, which is designed to disable, erase, or alter the Software, or any other files, data, or software.