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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promptly notify VerticalNet of any changes to the Neoforma Advertising Policies. 7.1.3 VerticalNet shall provide notice to Neoforma of each advertiser that agrees to place an advertisement on a Neoforma Site on the terms and conditions contained in the then current Neoforma Advertising Policies. Neoforma shall then have three business days after receipt of such notice to (a) accept or reject such advertiser, in its reasonable business discretion, and (b) notify VerticalNet of its decision. If, at the end of such three-day period, Neoforma has not responded to such notice, Neoforma shall be deemed to have accepted such advertiser. Neoforma shall then work with the advertiser to facilitate the placement of the advertisement and maintain such advertisement on the agreed-upon page of a Neoforma Site. Neoforma shall have the right to terminate its agreement with any such advertiser in its reasonable business discretion. Neoforma shall be responsible for, and shall have sole control of, all credit, billing and collection with the advertisements on the Neoforma Sites. VerticalNet shall have no authority to make collections on behalf of Neoforma. 7.1.4 During the Term, Neoforma shall not place any advertisements on a Neoforma Site for any VerticalNet Competitor. 7.2 ADVERTISEMENTS ON THE CO-BRANDED SITES. 11 12 7.2.1 During the Term, VerticalNet shall have the exclusive right to arrange for the sale of all advertising on the Co-Branded Sites, subject to reasonable approval of each such advertiser by Neoforma. Neoforma shall have two days to consider each VerticalNet request for approval of the sale of advertising on a Co-Branded Site. If, at then end of such two-day period, Neoforma has neither approved nor denied a request, VerticalNet's request shall be deemed approved. Source: NEOFORMA INC, S-1/A, 12/2/1999 7.2.2 VerticalNet will use reasonable efforts to sell advertisements on the Co-Branded Sites subject to VerticalNet's then current advertising policies (including rates and procedures). 8. CO-MARKETING ACTIVITIES 8.1 ADVERTISING CAMPAIGNS. VerticalNet and Neoforma shall use commercially reasonable efforts to co-promote the VerticalNet Medical Online Communities, the Co-Branded Sites, the VerticalNet Buyer's Guide, Neoforma Plan, Neoforma Shop and Neoforma Auction in mutually agreeable advertising, collateral marketing material and sales force activities. All co-promotion advertising materials produced by or on behalf of either Party (the "Originating Party") shall be subject to the written approval of the other Party (the "Receiving Party"), which approval shall not to be unreasonably withheld, delayed or conditioned. The Receiving Party shall notify the Originating Party of its approval or disapproval of such advertising materials as soon as practicable, but in any event within five business days after Receiving Party's receipt thereof. Any failure of the Receiving Party to respond within such five business day period shall be deemed disapproval of the advertising materials in question. 8.2 REGISTRATION. The parties shall use commercially reasonable efforts to coordinate their registration systems to create a "pass-through" registration system for users first accessing the other's Sites. If a user first accesses a Neoforma Site from a VerticalNet Site, such user shall be considered a VerticalNet user for the purposes of this Agreement, to the extent such user identifies him/her/itself, or Neoforma can reasonably identify such user, as a VerticalNet user. If a user first accesses a VerticalNet Site from a Neoforma Site, such user shall be considered a Neoforma user for the purposes of this Agreement, to the extent such user identifies him/her/itself, or VerticalNet can reasonably identify such user, as a Neoforma user. 8.3 CROSS-PROMOTION. The Parties shall place Links to each other's Sites in mutually agreeable locations and sizes on their respective Sites as soon as practicable, and in no event more than 15 days after the Effective Date. The Links shall remain on the Sites during the Term; provided, however, that such Links may be removed or relocated if the Parties mutually agree thereto. 8.4 NEWSLETTERS. 8.4.1 NEOFORMA NEWSLETTERS. If Neoforma distributes a newsletter to its users or customers, Neoforma shall promote the VerticalNet Auction, the Co-Branded Career Center and the Co-Branded Training and Education Center in each such newsletter, in a manner consistent with the manner in which other third party promotions are set forth in such newsletters. 12 13 8.4.2 VERTICALNET NEWSLETTERS. VerticalNet shall allow Neoforma to place sponsorships at no additional charge for Neoforma Shop, Neoforma Plan or Neoforma Auction in the VerticalNet newsletter distributed to its subscriber base two times during each calendar month, in a manner consistent with the manner in which other third party sponsorships are set forth in such newsletters. 8.5 LINKS. 8.5.1 Throughout the first six
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Extract the exact clause related to "Exclusivity" from the excerpt above.

assistant: During the Term, VerticalNet shall have the exclusive right to arrange for the sale of all advertising on the Co-Branded Sites, subject to reasonable approval of each such advertiser by Neoforma.