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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EXHIBIT 10.15 CO-BRANDING AGREEMENT This Agreement is made this 21st day of January 2003 by and between Lucent Technologies Inc., a Delaware corporation having a principal place of business at 600 Mountain Avenue, Murray Hill, New Jersey 07974 ("Lucent") and mPhase Technologies Inc., a New Jersey corporation located at 587 Connecticut Avenue, Norwalk, Connecticut 068545 ("mPhase") (each individually, "a Party" and, collectively, "the Parties"}. WHEREAS, mPhase wishes to use the Lucent Technologies name and Logo and the slogan TECHNOLOGY BY LUCENT TECHNOLOGIES on printed circuit boards, product packaging and in printed marketing materials ("Approved Uses") in connection with its multi-access product (the "Goods") and Lucent wishes to permit mPhase to do so. NOW THEREFORE, the Parties, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, agree as follows: 1. mPhase may apply only the exact logo shown on Schedule A of this Agreement (the "Lucent Co-Branding Logo"} in Approved Uses for mPhase's Goods. 2. mPhase agrees to abide by the guidelines appearing on Schedule B of this Agreement specifying the dimensions, requirements and specifications, and the review process related to use of the Lucent Co-Branding Logo. mPhase understands that these guidelines may be updated from time to time and agrees to abide by those updates as well as the guidelines provided herein. 3. In the event that mPhase's use of the Lucent Co-Branding Logo, in the sole judgment of Lucent, may adversely affect Lucent's rights to the mark shown on Schedule A or the marks and names LUCENT, LUCENT TECHNOLOGIES or LUCENT INNOVATION RING DESIGN, Lucent may upon written notification to mPhase, terminate this Agreement. 4. mPhase agrees that it acquires no rights to the Lucent Co-Branding Logo nor to the marks LUCENT, LUCENT TECHNOLOGIES or LUCENT INNOVATION RING DESIGN, by its use and that any use of the Lucent Co-Branding Logo by mPhase inures to the benefit of Lucent. 5. mPhase agrees not to adopt any designation which is confusingly similar to the Lucent Co-Branding Logo or Lucent's marks LUCENT, LUCENT TECHNOLOGIES or LUCENT INNOVATION RING DESIGN. Any attempt to do so shall be a breach of this Agreement and Lucent may terminate this Agreement without notice in the event of such a breach. 6. This Agreement shall terminate in the event of a significant change in the management or ownership of mPhase or in the event mPhase is the subject of any bankruptcy proceedings. 7. Lucent is generally aware of the current quality of mPhase's Goods. mPhase agrees to maintain the quality of its Goods associated with the Lucent Co-Branding Logo to a level of quality comparable to the current quality of their Goods. 8. If Lucent determines that mPhase's Goods are no longer maintained at the current level of quality, Lucent shall so notify mPhase, in writing, and Lucent shall have the right to terminate this Agreement. 9. mPhase agrees to allow Lucent to inspect the Approved Uses bearing the Lucent Co-Branding Logo, to ensure that those uses reviewed and approved pursuant to the procedure set forth in Schedule B continue to be in compliance with the terms of this Agreement. 10. In the event that mPhase becomes aware of any unauthorized use of the Lucent Co-Branding Logo or other Lucent marks by third parties, mPhase agrees to promptly notify Lucent and to cooperate fully, at Lucent's expense, in any enforcement of Lucent's rights against such third Source: MPHASE TECHNOLOGIES INC, 10-K, 9/11/2003 parties. Nothing contained in this paragraph shall be construed to require Lucent to enforce any rights against third parties or to restrict Lucent's rights to license or consent to such third parties' use of the Lucent Co-Branding Logo or any other Lucent marks. 11. The Term of this Agreement will commence on the date above, and shall continue for a term of one (1) year. mPhase shall have the right to annually renew this agreement for a period of one year upon each annual expiration with the written consent of Lucent, which written consent shall not be unreasonably withheld. Either party wishing to terminate the Agreement must give written notice to the other party at least thirty (30) days prior to the desired date of termination. 12. Upon termination of this Agreement, mPhase shall immediately cease use of the Lucent Co-Branding Logo, provided, however, that mPhase shall have no obligation to remove such Co-Branding Logo from any Goods sold prior to the date of such termination. -2- 13. Neither Party shall be liable to the other for special, incidental,
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Extract the exact clause related to "Source Code Escrow" from the excerpt above.