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:
"""
to the terms and conditions of this Agreement, WPT grants to Zynga a non-exclusive, non-assignable, non-sublicensable, royalty-free, paid up, limited license in the Territory to use and display WPT's Licensed Property solely as necessary to perform Zynga's obligations under this Agreement and as specifically described on Exhibit A, for the Term. d. Trademark Guidelines. In its use of the Licensed Property of the other party ("Licensee"), each party ("Licensor") will comply with any trademark usage guidelines that Licensor may communicate to Licensee from time to time. Each use of Licensor's marks by Licensee will be accompanied by the appropriate trademark symbol (either "™" or "®") and a legend specifying that such marks are trademarks of Licensor as specified on Exhibit B, and will be in accordance with Licensor's then-current trademark usage policies as provided in writing to Licensee from time to time. Licensee will provide Licensor with copies of any materials bearing any of Licensor's marks as requested by Licensor from time to time. If Licensee's use of any of Licensor's marks, or if any material bearing such marks, does not comply with the then-current trademark usage policies provided in writing by Licensor, Licensee will promptly remedy such deficiencies upon receipt of written notice of such deficiencies from Licensor. Other than the express licenses granted herein with respect to each Licensor's marks, nothing herein will grant to Licensee any other right, title or interest in Licensor's marks. All goodwill resulting from Licensee's use of Licensor's marks will inure solely to Licensor. Each party recognizes the great value of the publicity and good will associated with the Licensed Property and acknowledges that: (a) such good will is exclusively that of Licensor or Licensee, as applicable; and (b) the Licensed Property have acquired a secondary meaning as trademarks and/or identifications of Licensor or Licensee, as applicable, in the mind of the purchasing public. Licensee will not, at any time during or after this Agreement, register, attempt to register, claim any interest in, contest the use of, or otherwise adversely affect the validity of any of Licensor's marks (including, without limitation, any act or assistance to any act, which may infringe or lead to the infringement of any such marks). 4 Source: ALLIED ESPORTS ENTERTAINMENT, INC., 8-K, 8/15/2019 e. Approvals. The Licensed Property shall be displayed or used only in such form and in such manner as has been approved in writing (which may be by email) by Licensor pursuant to this Section 2 and Licensee shall ensure its usage of the Licensed Property solely as approved. Throughout the Term, including any renewals or extensions (if applicable), Licensee shall comply with reasonable quality standards, style guides and clear specifications communicated to Licensee and rights of approval of Licensor set forth in this Section 2 with respect to any and all of its usage of the Licensed Property. Subject to Licensor's prior written approval of any applicable Licensed Property (hereinafter the "Approved Content"), all Conforming Content will be deemed approved by Licensor. "Conforming Content" means any and all elements of the Approved Content which (i) do not represent deviations in quality, style, look-and-feel or other aspects of use from the Approved Content and (ii) are consistent with the aesthetic style or tone of the Approved Content. The parties will come to agreement with respect to Exhibit A as to whether prior written approval is needed in every instance or whether it is not needed after the first instance has been approved in writing (e.g., given exigencies in television production business, it is reasonable that Zynga would approve the use of its brand conceptually in elements of an episode but not need to re-approve the use in a similar manner for every episode the brand is used in; and similarly, given exigencies in the social gaming business, it is reasonable that WPT would approve use of its brand conceptually in elements of the Zynga platform but not need to re-approve the use in a similar manner for every poker tournament the brand is used in). i. Licensee may use textual and/or pictorial matter pertaining to the Licensed Property on such promotional, display and advertising material as may, in Licensee's reasonable judgment, promote the awareness, consumption and sale of the Licensed Property. All final advertising and promotional material using the Licensed Property must be submitted to Licensor for its prior written approval. All press releases respecting this Agreement or the relationship of the parties herein shall require prior written approval by the other party. ii. Licensor
"""

Extract the exact clause related to "Covenant Not To Sue" from the excerpt above.

assistant: Licensee will not, at any time during or after this Agreement, register, attempt to register, claim any interest in, contest the use of, or otherwise adversely affect the validity of any of Licensor's marks (including, without limitation, any act or assistance to any act, which may infringe or lead to the infringement of any such marks).