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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its own or together with other mobile terminal companies. 3.16 Party B shall mark the brand of "China Telecom Mobile Game" on the external promotion and advertisement of the cooperation contents of the Parties; the name of Party A may, but neither the logo of China Telecom nor the customer service number 10000 shall appear at such advertisements. The contents of the business described by Party B in any media (e.g. newspaper, radio, TV, leaflets, webpages, etc.) shall obtain the prior written consent of Party A, and Party B shall not post any business content description to which Party A objects. 3.17 When providing services to users, Party B shall not, in any manner including but not limited to coercion, cajole, fraud or cheat, in order to make users order tailored business and charge fees therefor, or otherwise increase any unnecessary costs to users. 3.18 Party B shall not advertise, or make any statement favorable for, any competitor having the same or similar business scope as Party A in the services it provides. Page 6 of 29 Jiangsu Telecom Contract No.: JSXCS1200166CC000 3.19 Party B may use its user name and passwords on the business management system to log in, and effect such functions as application for value-added business, company information maintenance, information exchange between the Parties regarding their cooperation in value-added business. Party B shall truthfully register/update in time its name, designated bank, account, contact person, customer service and such other information, and properly keep and maintain any contract information, settlement information, information on handling of complaints and breach of contract as generated by the business management system. Party B shall take proper care of, and shall not allow any third party to use, its user name and password for the business management system. Any losses incurred to either Party or users arising from other person's knowledge of Party B's user name and password for reasons attributable to Party B shall be borne by Party B on its own. 3.20 Party B shall have the right to obtain the information fee settled by Party A. 3.21 Except otherwise expressly agreed between the parties or agreed by Party A beforehand, Party B shall not transfer any cooperation business to a third party in any form whatsoever. Any transfer in violation hereof shall be deemed as a breach by Party B, for which Party B shall take relevant breaching liability and Party A may terminate this Agreement, suspend fee settlement and require Party B to undertake any direct or indirect loss thus caused. 3.22 In case of subject change of Party B (the change of holding entity of its business license or license for value-added telecommunications business (ISP Certificate)), Party B shall settle all fees payable to Party A and if there is no pending breach to be resolved, provide the approving notice on subject change issued by AIC, and may complete the relevant subject change procedures only after approved by Party A. 3.23 Party B shall pay performance deposit to Party A on time and in full amount as agreed herein. Article 4 Standard Business Practices 4.1 Party A shall provide Party B with the interface parameters of WAP gateway, SMS gateway and relevant platform, and assist Party B in business debugging, testing and opening. 4.2 The boundary to divide the respective areas of maintenance by the Parties shall be the gateway equipment and the interface from telecommunication business platform to Party B's equipment. The equipment on the inner side of the interface shall be maintained by Party A's maintenance department, and the equipment on the outer side of the interface shall be maintained by Party B. If Party B uses an exclusive line, then the interface cable and its connectivity shall be in the charge of the applicant for such exclusive line and the other Party shall provide assistance. 4.3 Party B shall be responsible for the building and maintenance of its systems, including all hardware equipment, system debugging, opening, and system maintenance work relating to the the wireless value-added business under this Agreement and the costs of each of the foregoing . 4.4 Party B shall be responsible for the interconnection of Party B's systems with the various gateways or servers of Party A and the application, renting and maintenance of relevant communication circuit, and bear the corresponding costs. Page 7 of 29 Jiangsu Telecom Contract No.: JSXCS1200166CC000 4.5 Party B guarantees that the debugging, connection and system maintenance work of its systems will not be carried out
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Extract the exact clause related to "Anti-Assignment" from the excerpt above.

assistant: Except otherwise expressly agreed between the parties or agreed by Party A beforehand, Party B shall not transfer any cooperation business to a third party in any form whatsoever.