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 10.4 CO-BRANDING AGREEMENT This Co-Branding Agreement (this "Agreement") dated September 30, 1999 (the "Effective Date") is entered into between VerticalNet, Inc., a Pennsylvania corporation having a principal place of business at 700 Dresher Road, Suite 100, Horsham, Pennsylvania, PA 19044 ("VerticalNet"), and PaperExchange.com, LLC, a Delaware limited liability company having a principal place of business at 545 Boylston Street, 8th Floor, Boston, MA 02116 ("PaperExchange"). In consideration of the mutual covenants herein, and intending to be legally bound hereby, the parties agree as follows: 1. DEFINITIONS 1.1. Affiliate shall mean, when used with reference to a party, any individual or entity directly or indirectly controlling, controlled by or under common control with such party. For purposes of this definition, "control" means the direct or indirect ownership of at least 50% of the outstanding voting securities of a party, or the right to control the policy decisions of such party. 1.2. Career Center Net Revenue shall have the meaning ascribed thereto in Section 7.1.1 [Co-Branded Career Center]. 1.3. Co-Branded Career Center shall mean the "Career Center" portion of Pulp and Paper Online located at: http://www.pulpandpaperonline.com/Content/CareerCenter/Home/JobScan_Home.asp (or a successor Site thereto). 1.4. Co-Branded Equipment Listings shall mean the "Auctions" portion of Pulp and Paper Online located at: http://www2.pulpandpaperonline.com/content/auctions/home.asp (or a successor Site thereto). 1.5. Co-Branded Sites shall mean the Co-Branded Career Center and the Co-Branded Equipment Listings. 1.6. Co-Branded URLs shall mean the mutually agreed-upon URLs which shall be registered jointly by VerticalNet and PaperExchange and shall route users through to the Co-Branded Sites. 1.7. Confidential Information shall mean all proprietary and confidential information of a party, including, without limitation, trade secrets, technical information, business information, sales information, customer and potential customer lists and identities, product sales plans, sublicense agreements, inventions, developments, discoveries, software, know-how, methods, techniques, formulae, data, processes and other trade secrets and proprietary ideas, whether or not protectable under patent, trademark, copyright or other areas of law, that the other party has access to or receives, but does not include information that (a) is or becomes publicly available through no fault of receiving party; (b) was already known to the receiving party at the time it was disclosed to the receiving party, as evidenced by written records of the receiving party; (c) is independently developed by employees of the receiving party who had no knowledge of or * Confidential Treatment Requested: material has been omitted and filed separately with the Commission. access to such information, as evidenced by written records of the receiving party; or (d) is received from a third party who is under no obligation of confidentiality to the disclosing party. 1.8. Equipment Listings Net Revenue shall have the meaning ascribed thereto in Section 7.1.2 [Co-Branded Equipment Listings]. 1.9. Initial Term shall mean the Effective Date through the day prior to the fourth anniversary of the Effective Date, unless earlier terminated pursuant to Section 8. 1.10. Intellectual Property shall mean any and all trade secrets, patents, copyrights, trademarks, URLs, trade dress, brand features, know-how and similar rights of any type under the laws of any applicable governmental authority, including, without limitation, all applications and registrations relating to any of the foregoing. 1.11. Intellectual Property Rights shall mean all rights in and to Intellectual Property. 1.12. Link shall mean a link (including, but not limited to, a hyperlink, button or banner) that connects two Sites in a manner so that when a user clicks on the link, the user is transferred directly from one Site to a second Site. A "Link from Site A to Site B" indicates that Site A is the Site of origin and Site B is the Site to which the user is linked. 1.13. Net Advertising Revenue shall mean the gross amount billed to an advertiser for the sale of advertising on the Third Party Advertising Allocation on the PaperExchange Site, less (a) credits for claims, allowances, retroactive price reductions or returned goods, and (b) sales, excise, use, value-added and other similar taxes (excluding income taxes) actually paid, if applicable. 1.14. Packaging Online shall mean the Site located at www.packagingonline.com (or a successor Site thereto). 1.15. PaperExchange Career Content shall have the meaning ascribed thereto in Section 2.2 [CO-BRANDED CAREER CENTER AND CO-BRANDED ...]. 1.16. PaperExchange Competitor shall mean any exchange, auction or reverse auction for the sale, purchase and/or exchange of pulp, paper and paper packaging. 1.17. PaperExchange Equipment Content shall have the meaning ascribed thereto in Section 2.2 [CO-BRANDED CAREER CENTER AND CO-BRANDED ...]. 1.18. PaperExchange Deliverable shall mean any
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Extract the exact clause related to "Parties" from the excerpt above.