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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Licensed Intellectual Property, which right and license shall be limited to that which is necessary for LEA to (i) develop and create Educational Materials and (ii) develop, promote and conduct the Business worldwide , unless the license is earlier terminated as provided herein. 2.2 LEA has the right to modify the Licensed Intellectual Property and to create derivative works (the "Derivative Works"); provided that such Derivative Works may be used, copied, distributed, performed and/or displayed only in connection with the Business; and provided further that LEA will not distribute Products embodying the Derivative Works other than to end users for personal use only in connection with the Business, and not for sale, distribution or re-licensing by such end users. For the avoidance of doubt, T&B shall remain the owner of all right, title and interest in and to the Derivative Works from inception. 2.3 T&B and LEA shall promptly notify one another in writing of any alleged infringement of the Licensed Intellectual Property by a third party. Within fifteen (15) days of the receipt of such notice or such other period as may be agreed to by the parties, T&B and LEA shall meet and confer to formulate a strategy for resolving the alleged infringement. T&B and LEA (to the extent permitted by law) each shall have the right to institute an action against such third party based upon such infringement of the Licensed Intellectual Property. 2.4 Should either T&B or LEA commence a suit under the provisions of this Section 15, and thereafter elect to abandon the same, it shall give timely notice of the other party who may, if it so desires, continue to prosecute such suit. 2.5 T&B and LEA shall cooperate in any legal proceeding concerning an alleged infringement of the Licensed Intellectual Property. Each party shall, to the fullest extent reasonable, make its employees, records, and information available to the other party as relevant to the legal process. 3 Source: LEGACY EDUCATION ALLIANCE, INC., 10-K, 3/30/2020 Certain identified information has been excluded from this exhibit because it is both (i) not material and (ii) would be competitively harmful if publicly disclosed. 3. Limitations, Restrictions and Covenants 3.1. During the Term, the LEA shall not use the Licensed Intellectual Property other than as permitted by this Agreement. 3.2. During the Term, T&B shall promptly disclose to LEA on an ongoing basis all additions, improvements, changes, replacements, or enhancements to T&B's Proprietary Rights not previously disclosed. 3.3 T&B shall not, during the Term, grant any third party a license to use the Licensed Intellectual Property within the Exclusive Field of Use. Further, during the Term, except as otherwise provided herein, neither T&B nor any of its Affiliates may (1) offer to sell or sell any product or service that is the same or similar to the Products in the Exclusive Field of Use, or (2) contact, solicit, or direct any person or entity to contact or solicit, any of the customers of (or customers set forth in the Customer Data) for the purpose of providing any products or services that are the same or similar to the Products; provided, however, that T&B, in its sole and absolute discretion, shall have the right to terminate this Agreement, including all rights and licenses granted to LEA herein, if and as of the date that any monthly Royalty Payment (as defined in 9.3, below) payable to T&B does not exceed the Minimum Guaranteed Royalty for six (6) consecutive months. 3.4. LEA may distribute goods and services embodying the Licensed Intellectual Property to end users for personal use only in connect with the Business, and for resale, distribution or re-licensing by such end users. 3.5 LEA acknowledges and agrees that, except as otherwise specifically provided for herein, this Agreement grants LEA no title or right of ownership in or to the Licensed Intellectual Property. LEA shall not at any time do or cause to be done any act, omission, or thing contesting or in any way impairing or tending to impair any part of T&B's right, title and interest in the Licensed Intellectual Property. 3.6 In the event LEA shall be deemed to have acquired any ownership rights in the Licensed Intellectual Property, the LEA shall assign, and agrees to execute all documents reasonably requested by T&B to assign, all such rights in the Licensed Intellectual Property to T&B or its nominee. 4. Conduct of the Business 4.1 LEA shall provide administrative and operational services for the conduct of the Business,
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Extract the exact clause related to "Covenant Not To Sue" from the excerpt above.

assistant: LEA shall not at any time do or cause to be done any act, omission, or thing contesting or in any way impairing or tending to impair any part of T&B's right, title and interest in the Licensed Intellectual Property.