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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RARE ELEMENT RESOURCES LTD, SC 13D, 10/19/2017 Rare Element Resources Ltd. EXECUTION COPY IP Rights Agreement IX.Severability 9.00 The Parties agree that if any part, term or provision of this IP Agreement is found illegal or in conflict with any valid controlling law, the validity of the remaining provisions will not be affected thereby. 9.01 Should any provision of this IP Agreement be held by a court of law to be illegal, invalid or unenforceable, such provision shall be replaced by such provision as most closely reflects the intent of the invalid provision, and the legality, validity and enforceability of the remaining provisions of this Agreement will not be affected or impaired thereby. X. Waiver, Integration, Alteration 10.00 The waiver of a breach hereunder may be effected only by a writing signed by the waiving Party and will not constitute a waiver of any other breach. 10.01 This IP Agreement, together with the Investment Agreement and any other documents or agreements executed in connection with the transactions contemplated thereunder, represents the entire understanding between the Parties, and supersedes all other agreements, express or implied, between the Parties concerning the Patents and Technical Information. XI. Execution 11.00 This IP Agreement may be executed in counterparts, all of which when taken together shall be considered one and the same agreement and shall become effective when counterparts have been signed by each Party and delivered to each other Party, it being understood that the Parties need not sign the same counterpart. In the event that any signature is delivered by facsimile transmission or by e-mail delivery of a ".pdf" format data file, such signature shall create a valid and binding obligation of the Party executing (or on whose behalf such signature is executed) with the same force and effect as if such facsimile or ".pdf" signature page were an original thereof. Page 11 of 15 Source: RARE ELEMENT RESOURCES LTD, SC 13D, 10/19/2017 Rare Element Resources Ltd. EXECUTION COPY IP Rights Agreement XII. Cooperation 12.00 Each Party will execute any instruments reasonably believed by the other Party to be necessary to implement the provisions of this IP Agreement. XIII. Construction 13.00 This IP Agreement will be construed in accordance with the substantive laws of the state of New York and of the United States of America. XIV. Exportation of Technical Information 14.00 Investor agrees that it will not export the Technical Information furnished to Investor either directly or indirectly by Company, to any destination or Person prohibited by the U.S. Export Administration Regulations or other U.S. export control laws and regulations. 14.01 Company agrees that it will not export any information relating to Improvements or otherwise furnished to Investor either directly or indirectly by Investor Company, to any destination or Person prohibited by the U.S. Export Administration Regulations or other U.S. export control laws and regulations. XV. Notices Under this IP Agreement 15.00 All written communications and notices between the Parties relating to this IP Agreement shall be made in the manner set forth in the Investment Agreement. XVI. Term and Termination 16.00 Unless earlier terminated in accordance with the terms of this Article XVI, this IP Agreement and the licenses granted herein will continue in effect from the Effective Date until the expiration of the last to expire of the Patents and any additional period of time thereafter that any of the Patents remain enforceable such as in the United States where a party can sue for infringement after a patent expires and seek damages for any infringement of the patent during the six years immediately preceding the filing of a suit for infringement. Page 12 of 15 Source: RARE ELEMENT RESOURCES LTD, SC 13D, 10/19/2017 Rare Element Resources Ltd. EXECUTION COPY IP Rights Agreement 16.01 Investor at any time may provide written notice to Company of a material breach of this IP Agreement. If Company fails to cure the identified breach within thirty (30) days after the date of the notice, Investor may terminate this IP Agreement by written notice to Company. 16.02 If the Option is not exercised before the expiration of the Option Period, Company may provide written notice to Investor of a material breach of this IP Agreement. If Investor fails to cure the identified breach within thirty (30) days after the date of the notice, Company may terminate this IP Agreement by written notice to Investor. If the Option is exercised before the expiration of the Option Period, Company may not terminate this IP Agreement for material
"""

Extract the exact clause related to "Warranty Duration" from the excerpt above.

assistant: Not found.