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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consent is to be effective. No failure or delay by a party in exercising any right, power or privilege hereunder shall operate as a waiver thereof, nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any right, power or privilege hereunder. 12. Notices. All notices, consents, requests, instructions, approvals and other communications provided for herein and all legal process in regard hereto shall be in writing and shall be deemed validly given, made or served, when delivered in person or sent by overnight courier, when actually received during normal business hours at the address specified in this subsection: If to the Company: Allison Transmission Holdings, Inc. Mail Code L-25 One Allison Way Indianapolis, IN 46222-3271 Attention: General Counsel If to the ValueAct Group: ValueAct Capital Management, L.P. One Letterman Drive Building D, 4t h Floor San Francisco, CA 94129 Attention: General Counsel 13. Severability. If at any time subsequent to the date hereof, any provision of this Agreement shall be held by any court of competent jurisdiction to be illegal, void or unenforceable, such provision shall be of no force and effect, but the illegality or unenforceability of such provision shall have no effect upon the legality or enforceability of any other provision of this Agreement. 6 14. Counterparts. This Agreement may be executed in two or more counterparts either manually or by electronic or digital signature (including by facsimile or electronic mail transmission), each of which shall be deemed to be an original and all of which together shall constitute a single binding agreement on the parties, notwithstanding that not all parties are signatories to the same counterpart. 15. No Third Party Beneficiaries; Assignment. This Agreement is solely for the benefit of the parties hereto and is not binding upon or enforceable by any other persons. No party to this Agreement may assign its rights or delegate its obligations under this Agreement, whether by operation of law or otherwise, and any assignment in contravention hereof shall be null and void. Nothing in this Agreement, whether express or implied, is intended to or shall confer any rights, benefits or remedies under or by reason of this Agreement on any persons other than the parties hereto, nor is anything in this Agreement intended to relieve or discharge the obligation or liability of any third persons to any party. 16. Interpretation and Construction. When a reference is made in this Agreement to a Section, such reference shall be to a Section of this Agreement, unless otherwise indicated. The headings contained in this Agreement are for reference purposes only and shall not affect in any way the meaning or interpretation of this Agreement. Whenever the words "include," "includes" and "including" are used in this Agreement, they shall be deemed to be followed by the words "without limitation." The words "hereof, "herein" and "hereunder" and words of similar import when used in this Agreement shall refer to this Agreement as a whole and not to any particular provision of this Agreement. The word "will" shall be construed to have the same meaning as the word "shall." The words "dates hereof" will refer to the date of this Agreement. The word "or" is not exclusive. The definitions contained in this Agreement are applicable to the singular as well as the plural forms of such terms. Any agreement, instrument, law, rule or statute defined or referred to herein means, unless otherwise indicated, such agreement, instrument, law, rule or statute as from time to time amended, modified or supplemented. Each of the parties hereto acknowledges that it has been represented by counsel of its choice throughout all negotiations that have preceded the execution of this Agreement, and that it has executed the same with the advice of said independent counsel. Each party cooperated and participated in the drafting and preparation of this Agreement and the documents referred to herein, and any and all drafts relating thereto exchanged among the parties shall be deemed the work product of all of the parties and may not be construed against any party by reason of its drafting or preparation. Accordingly, any rule of law or any legal decision that would require interpretation of any ambiguities in this Agreement against any party that drafted or prepared it is of no application and is hereby expressly waived by each of the parties hereto, and any controversy over interpretations of this Agreement shall be decided without regards to events of drafting or preparation.
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Extract the exact clause related to "Covenant Not To Sue" from the excerpt above.

assistant: Not found.