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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excise, state, and local transaction taxes imposed upon the sale of Material, Delivery of Deliverables, and provision of Services under this Agreement. All such taxes must be stated as separate items on the applicable Material, Deliverable, or Services invoice listing the taxing jurisdiction imposing the tax. Installation, labor and other non-taxable charges must be separately stated. AT&T shall pay all applicable taxes to Vendor that are stated on and at the time the Material, Deliverables, or Services invoice is submitted by Vendor. Vendor shall remit taxes to the appropriate taxing authorities. Vendor shall honor tax exemption certificates, and other appropriate documents, which AT&T provides to Vendor, pursuant to relevant tax provisions of the taxing jurisdiction providing the exemption. Proprietary and Confidential This Agreement and information contained therein is not for use or disclosure outside of AT&T, its Affiliates, and third party representatives, and Vendor except under written agreement by the contracting parties. 37 Source: ATN INTERNATIONAL, INC., 10-Q, 11/8/2019 (b) Vendor will pay any penalty, interest, additional tax, or other charge that may be levied or assessed as a result of the delay or failure of Vendor, for any reason other than AT&T's failure to reimburse Vendor in a timely manner for such amounts, to pay any tax or file any return or information required by law, rule, or regulation or by this Agreement to be paid or filed by Vendor. (c) Upon AT&T's request, the Parties shall consult with respect to the basis and rates upon which Vendor shall pay any taxes or fees for which AT&T is obligated to reimburse Vendor under this Agreement. If AT&T determines that, in good faith and pursuant to applicable Law, any such taxes or fees are not payable or should be paid on a basis less than the full price or at rates less than the full tax rate, AT&T shall notify Vendor in writing of such determinations, Vendor shall make payment in accordance with such determinations, and AT&T shall be responsible for such determinations. If collection is sought by the taxing authority for a greater amount of taxes than that so determined by AT&T, Vendor shall promptly notify AT&T. If AT&T desires to contest such collection, AT&T shall promptly notify Vendor. Vendor shall cooperate with AT&T in contesting such determination, but AT&T shall be responsible and shall reimburse Vendor for any tax, interest, or penalty in excess of AT&T's determination and shall reimburse Vendor for Litigation Expense incurred by Vendor in connection with contesting such determination. (d) If the parties agree, where such agreement shall not be unreasonably withheld, conditioned, or delayed, that AT&T has paid Vendor for any taxes in excess of the amount that AT&T is obligated to pay Vendor under this Agreement, AT&T and Vendor shall consult in good faith to determine the appropriate method(s) to seek recovery of such excess payments, which method(s) may include, but are not limited to, (i) Vendor crediting any excess payments against tax amounts or other payments due from AT&T solely to the extent Vendor has successfully made corresponding adjustments to its payments to the relevant tax authority, (ii) Vendor timely filing claims for refund and any other documents required to recover any excess payments and Vendor promptly remitting to AT&T all such refunds and interest received, and (iii) Vendor immediately refunding to AT&T such excess payments. (e) If any taxing authority advises Vendor that it intends to audit Vendor with respect to any taxes for which AT&T is obligated to reimburse Vendor under this Agreement, Vendor shall (i) promptly so notify AT&T, (ii) afford AT&T an opportunity to participate with Vendor in such audit with respect to such taxes, and (iii) keep AT&T fully informed as to the progress of such audit. Except as set forth in Subsection (c) above, each Party shall bear its own expenses with respect to any such audit, and the responsibility for any additional tax, interest, or penalty resulting from such audit is to be determined in accordance with the applicable provisions of this Section 3.36. Vendor's failure to comply with the notification requirements of this Section 3.36 will relieve AT&T of its responsibility to reimburse Vendor for taxes only to the extent that Vendor's failure actually and materially prejudiced AT&T's ability to contest imposition or assessment of those taxes. (f) In addition to its rights under Subsections (c), (d), and (e) above with respect to any tax or tax controversy covered by this Section 3.36, AT&T is entitled to contest, pursuant to applicable Law and
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Extract the exact clause related to "Termination For Convenience" from the excerpt above.

assistant: Not found.