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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VerticalNet and Impresse shall negotiate in good faith a compensation structure that seeks to provide VerticalNet with compensation equal to that set forth in Section 4.6 [REVENUE SHARING]. 4.7. TAXES. All payments required under this Agreement are exclusive of federal, state, local and foreign taxes, duties, tariffs, levies and similar assessments. When applicable, such taxes shall appear as separate items on a party's invoice or statement to the other party. Payment of such taxes or charges shall be the responsibility of the party whose obligation it is under this Agreement to make the payment in respect of which such taxes are assessed, excluding any taxes based upon the other party's net income. In lieu thereof, a party shall provide the other party with a tax or levy exemption certificate acceptable to the taxing or levying authority. Source: IMPRESSE CORP, S-1/A, 3/22/2000 4.8. AUDITS. During the term of this Agreement and for one year thereafter, VerticalNet shall have the right to appoint a certified public accountant to audit Impresse's financial records relating to such payment to verify the accuracy of Impresse's financial records in order to verify the amount of the payments owed and/or paid hereunder, but no more frequently than once per year. If the amount owed by Impresse to VerticalNet was underpaid, the additional amount owed shall be paid to VerticalNet within 15 days of notice of such underpayment to Impresse. If the amount owed by Impresse to VerticalNet was underpaid in excess of 10% of the amount owed, the fees of such audit shall also be paid to VerticalNet within 15 days of notice of such to Impresse. If the amount owed by Impresse to VerticalNet was overpaid, the excess amount paid shall be returned by VerticalNet within 15 days of notice of such overpayment. VerticalNet shall give reasonable advance notice to Impresse of such audit and each audit shall be conducted in a manner that does not cause unreasonable disruption to the conduct of business by Impresse. The results of any such audit shall be deemed to be Confidential Information and may not be disclosed by either party or its certified public accountants except as may be necessary to enforce such party's rights. 4.9. INTEREST. All payments not paid by the date such payments are due shall bear interest from the due date to the date payments are actually paid at the lower of (i) 1% per month or (ii) the maximum rate permitted by law. 5. TERMINATION AND RENEWAL 5.1. The Term of this Agreement shall begin on the Effective Date and shall end fifteen months therefrom. 6 5.2. Either party may terminate this Agreement immediately upon written notice to the other party in the event of any material breach of a term of this Agreement by such other party that remains uncured 30 days after written notice of such breach was received by such other party or, if the breach is not reasonably capable of cure within 30 days, such longer period, not to exceed 60 days, so long as the cure is commenced within the 30-day period and thereafter is diligently prosecuted to completion as soon as possible and in any event within 60 days. 5.3. Upon termination or expiration of this Agreement, (i) Impresse shall no longer have the right to use any VerticalNet Mark, (ii) VerticalNet shall no longer have the right to use any Impresse Mark; (iii) Impresse may no longer make any Co-Branded Content available for access and use through the Co-Branded Site; (iv) VerticalNet shall cease framing the Window in the Co-Branded Site; (v) VerticalNet shall remove the V-Solutions Link from the V-Solutions Area; and (vi) VerticalNet shall cease displaying or transmitting all Banners and Newsletters of Impresse. 5.4. Following expiration or termination of this Agreement, the terms and provisions of Article 4 [THE COMMERCIAL TERMS] above shall continue to govern Impresse's payment obligations for any payment obligations accruing during the term of this Agreement. Following termination, Impresse shall provide VerticalNet with a final accounting with respect to this Agreement and tender payment of amounts due under Article 4 [THE COMMERCIAL TERMS] at the next scheduled payment date. 6. DISPUTE RESOLUTION 6.1. NEGOTIATION AND ESCALATION. If any controversy or claim arises relating to this Agreement, the parties will attempt in good faith to negotiate a solution to their differences, including progressively escalating any controversy or claim through senior levels of management. If negotiation does not result in a resolution within 30 days of the date one party first notifies
"""

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

assistant: Not found.