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 Shared Library Materials may contain design standards and design manuals related solely to nuclear content set forth on Schedule 4.4 (collectively, the "Nuclear Design Manuals"), and that such Nuclear Design Manuals are deemed to be owned by RemainCo, subject only to SpinCo's right to confirm that such Nuclear Design Manuals, including each page therein, are marked with the engineering standards series and numbering set forth on Schedule 4.4. SpinCo's right to such confirmation is expressly limited to confirmation of the engineering standards series and numbering system contained in or on such Nuclear Design Materials for purposes of confirmation of the document's identification and does not include the right to analyze, review, or approve any of the content contained in any such Nuclear Design Manual. Section 4.5 Confidentiality and Trade Secret Status of Shared Library Materials. The Parties acknowledge that the Research Documents contained within the Shared Library Materials likely contain proprietary trade secret information. Each Party will use reasonable efforts to maintain confidentiality of any trade secret or proprietary information contained within the Shared Library Materials in a manner materially consistent with the how the applicable Party protects its own trade secret or proprietary information. Section 4.6 Third Party Materials Contained in the Shared Library Materials. The Parties acknowledge that the Shared Library Materials contain Third Party-owned material, including, without limitation, the Reference Materials, and this Agreement does not include any license to utilize such Third Party-owned material or any representation, warranty or indemnity from or to SpinCo or RemainCo or any member of the SpinCo Group or RemainCo Group related to the use of such Third Party-owned material in connection with the Shared Library Materials. ARTICLE V INTELLECTUAL PROPERTY LICENSES AND COVENANTS Section 5.1 Cross-License of Shared Know-How. (a) SpinCo, for itself and as representative of all other members of the SpinCo Group, hereby grants to RemainCo (x) a perpetual, irrevocable, exclusive, royalty-free, worldwide right and license with the right to grant sublicenses (solely as set forth in Section 5.6) to use the SpinCo Know- How currently or previously used in connection with the RemainCo Business or otherwise in the possession of RemainCo or any member of the RemainCo Group as of Distribution Date (the "Licensed SpinCo Know-How"), for the continued operation of the RemainCo Business and any future extensions of the RemainCo Business in the RemainCo Core Field and (y) a perpetual, irrevocable, non-exclusive, royalty-free, worldwide right and license with the right to grant sublicenses (solely as set forth in Section 5.6) to use the Licensed SpinCo Know-How for the continued operation of the RemainCo Business and any future extensions of the RemainCo Business in any field other than the RemainCo Core Field or the SpinCo Core Field; provided, however, the foregoing licenses shall not extend to (i) SpinCo Know-How 13 licensed by SpinCo or any other member of the SpinCo Group if and to the extent the licensing of same to RemainCo would constitute a breach of an agreement with any Third Party executed prior to the Effective Date or result in any expense to SpinCo or any member of the SpinCo Group for payments to such Third Party or (ii) any intellectual property not owned by one or more members of the SpinCo Group, or as to which no member of the SpinCo Group has the right to grant sublicenses, as of the Effective Date. (b) RemainCo, for itself and as representative of all other members of the RemainCo Group, hereby grants to SpinCo (x) a perpetual, irrevocable, exclusive, royalty-free, worldwide right and license with the right to grant sublicenses (solely as set forth in Section 5.6) to use the RemainCo Know-How currently or previously used in connection with the SpinCo Business or otherwise in the possession of SpinCo or any member of the SpinCo Group as of the Distribution Date (the "Licensed RemainCo Know-How"), for the continued operation of the SpinCo Business and any future extensions of the SpinCo Business in the SpinCo Core Field and (y) a perpetual, irrevocable, non-exclusive, royalty-free, worldwide right and license with the right to grant sublicenses (solely as set forth in Section 5.6) to use the Licensed RemainCo Know-How for the continued operation of the SpinCo Business and any future extensions of the SpinCo Business in any field other than the RemainCo Core Field or the SpinCo Core Field; provided, however, the foregoing licenses shall not extend to (i) RemainCo Know-How licensed by RemainCo or any other member of the RemainCo Group if and to the extent the
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Extract the exact clause related to "Ip Ownership Assignment" from the excerpt above.