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 10.16 DRAFT (Americas) 1/12/00 (Rev 1) SUPPORT AND MAINTENANCE AGREEMENT This Support and Maintenance Agreement ("Agreement") is entered into and is effective as of the ____ day of _______________2000 (the "Effective Date") by and between XACCT Technologies, Inc., a Delaware corporation ("XACCT") with its principal place of business at 2900 Lakeside Drive, Suite 100, Santa Clara, California 95054 and ________________________________, a _______________corporation ("Licensee") with its principal place of business at _________________________________. This Agreement sets forth the terms and conditions under which XACCT will provide Product Maintenance (as defined below) and Support Services (as defined below) for the Product which is licensed by Licensee pursuant to XACCT's End User Software License Agreement ("License Agreement"). Except where superseded by this Agreement, all other terms and conditions of the License Agreement are incorporated by reference. Capitalized terms that are not defined in Section 1. below or elsewhere in this Agreement have the same meaning as in the License Agreement. 1. DEFINITIONS 1.1 "Designated Support Contact " means Licensee's employee who is authorized to contact the XACCT support center. 1.2 "Incident" means a single, discrete, malfunction or other problem which may require more than one (1) response before it is closed. 1.3 "Major Release" means a version of the Product containing significant changes in functionality which usually will be designated with a whole number product version change such as 3.x to 4.x. 1.4 "Minor Release" means a version of the Product containing minor improvements which usually will be designated with a one (1) decimal version change such as 3.x to 3.x; also sometimes referred to as "dot releases." 1.5 "Product Maintenance" means the Product updates and revisions that are available from XACCT and selected by Licensee, as further referenced herein and the attachments hereto as may be amended from time to time. 1.6 "Support Services" means the software support services that are available from XACCT and selected by Licensee, as further referenced herein and the attachments hereto as may be amended from time to time. 2. COVERAGE AND PAYMENT OF FEES Licensee may purchase the level of Product Maintenance and Support Services set forth in Attachment 1 to this Agreement. XACCT will provide the Product Maintenance and Support Services purchased by Licensee subject to the terms and conditions of this Agreement and the License Agreement. Fees shall be payable within thirty (30) days of invoice which shall be exclusive of any applicable local, state, federal, use, excise, value added, GST or other taxes imposed on the fees payable for the Product Maintenance and Support Services which shall be the responsibility of Licensee. 3. SUPPORT SERVICES 3.1 XACCT will provide reasonable commercial efforts to provide the appropriate solutions for reported Incidents. Initial response times for reported Incidents are as set forth in Attachment 1. 3.2 In order for Licensee to receive the Support Services referenced above, Licensee must: (a) Appoint Designated Support Contact(s), trained and qualified, who will maintain the integrity of the&sbsp;Product and who will act as Licensee's liaison for all technical communications with XACCT. The number of Designated Support Contact(s) will be determined by the level of Support Services purchased by Licensee set forth in Attachment 1referenced in Section 2. Names of Designated Support Contact(s) must be provided to XACCT prior to initial contact with the XACCT support center. All technical communications by Licensee to XACCT shall only be made by the Designated Support Contact(s). All information and materials provided to Licensee by XACCT pursuant to this Agreement will be routed to the Designated Support Contact(s). Licensee may change the Designated Support Contact(s) upon written notice to XACCT; (b) Promptly obtain training on the use of the Product for the Designated Support Contact(s), and any other employee substituting or replacing the Designated Support Contact(s); (c) Subject to Licensee's applicable security requirements, provide XACCT with access to and use of all information and system facilities including but not limited to a modem connection to Licensee's systems determined necessary by XACCT to provide timely Support Services pursuant to this Agreement; (d) Follow operating instructions and procedures as specified in, but not limited to, XACCT's documentation and other correspondence related to the Product; (e) Follow procedures and recommendations provided by the XACCT support center in an effort to correct problems; or (f) Notify XACCT of a malfunction or other problem in accordance with XACCT's then current problem reporting procedures and as provided in Attachment 1. If XACCT determines that a problem reported by Licensee is not due to an error in the Product, XACCT will
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Extract the exact clause related to "Document Name" from the excerpt above.

assistant: Support and Maintenance Agreement