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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purpose of agreeing to the terms of this Section and Section 15.12. Section 15.12 OPTION TO PURCHASE. Skunkware and Licensor hereby grant to Licensee the exclusive and irrevocable right and option to purchase (the "Option"), at Licensee's election, either (i) all of the assets of Licensor or (ii) all of the issued and outstanding stock of Licensor. Such option shall be exercisable during a period (the "Option Period") commencing on and including the earlier of (i) the date upon which Licensee shall have paid to Licensor, in any single fiscal year of Licensee, royalty payments hereunder in the aggregate amount of $10,000,000 or (ii) January 1, 2002, and ending upon the expiration or sooner termination of this Agreement. Licensee's exercise of the Option is at its sole discretion. Licensee may exercise the Option by written notice to Licensor and Skunkware at any time during the Option Period. Upon any such exercise of the Option, Licensee and Licensor or Skunkware (as the case may be) shall proceed to diligently and in good faith negotiate and execute a definitive purchase and sale agreement for Licensor's acquisition of all of the assets of, or outstanding capital stock in, Licensor, as the case may be. In the event that Licensee and Licensor or Skunkware, as the case may be, are unable to agree on any terms or conditions for such acquisition, the same shall be submitted to arbitration in accordance with the rules and procedures of the American Arbitration Association, with the arbitrator(s) to be experienced in the mainframe software industry. Notwithstanding the foregoing provision for arbitration concerning the terms of any purchase and sale agreement, and without limiting any other 5 conditions that may be included in any such purchase and sale agreement, Licensee shall have no obligation to consummate the acquisition of the assets of, or stock in, Licensor pursuant to its exercise of the Option if Licensee's board of directors should determine, in its sole discretion, that such acquisition would not be accretive to the value of Licensee. The definitive purchase and sale agreement shall provide that License may pay the purchase price thereunder in cash, in shares of its Common Stock or in some combination thereof. So long as the Option shall be in existence (whether or not exercisable), Skunkware and Licensor agree that Licensor will conduct its business in the ordinary course and will not, without the prior written consent of Licensee, merge or consolidated with any other entity, sell all or substantially all of its assets, grant or permit to exist any lien or encumbrance on any material portion of its assets, issue any securities to any person other than Skunkware or engage in any other transaction or enter into any other agreement other than in the ordinary course of business. Skunkware further agrees that, so long as the Option shall be in existence (whether or not exercisable), it shall be and remain the sole Stockholder Licensor, and Licensor shall not issue to any other person or entity any stock, warrants or similar rights to acquire equity interests in Licensor. 9. MISCELLANEOUS. (a) Capitalized terms used in this Amendment that are not defined herein shall have the meanings provided therefor in the Distributor Agreement. (b) The captions used for the Sections in this Amendment are inserted only as a matter of convenience and for reference and in no way define, limit or describe the scope or the intent of this Amendment or any Section hereof. (c) This Amendment may be executed in one or more counterparts, each of which shall be deemed an original and all of which, taken together, shall be construed as a single instrument. (d) In the event any provision of this Amendment is declared or adjudged to be unenforceable or unlawful by any court, then such unenforceable or unlawful provision shall be excised herefrom, and the remainder of this Amendment, together with all rights and remedies granted thereby, shall continue and remain in full force and effect. 6 (e) The Distributor Agreement, as amended by this Amendment, constitutes the entire agreement between the parties hereto with respect to the matters covered hereby and thereby. All prior negotiations, representations and agreements with respect thereto not incorporated in this Amendment or the Distributor Agreement are hereby canceled. As modified hereby, the Distributor Agreement shall continue in full force and effect and be binding upon the parties hereto and their respective successors and permitted assigns. References to the Distributor Agreement after the date hereof shall mean the
"""

Extract the exact clause related to "Source Code Escrow" from the excerpt above.

assistant: Not found.