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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3.5.4 Both parties are entitled to reports of sales and to conduct periodic audits to ensure accuracy of Payments as follows: a. Each party will provide to the other a quarterly report (in hard copy and electronic copy (if applicable)) showing the AMR Product Suite sales including the Gross Proceeds and the Production Costs. b. Each party shall have the right to conduct an audit after the end of each calendar year to verify the accuracy of the other party's quarterly reports for that year, provided the audit must be initiated no later than June 30th of each year, and that if no such audit is conducted, then the quarterly reports for that year will be deemed accurate. c. In the event a Payee's audit shows that the Gross Proceeds or Production Costs of the Payor resulted in an under-payment to the Payee, then the Payor shall have the right, at the Payor's cost, to have its own auditor verify the Payee's audit. If the Payor audit confirms the report of the Payee's auditor, then the Payor will pay the deficiency within fifteen (15) days from the time Payee invoices for the deficiency. d. In the event a Payee's audit shows that the Gross Proceeds or Production Costs of the Payor resulted in an under-payment of more than three percent (3.0%) to the Payee, then the Payor shall have the right, at the Payor's cost, to have its own auditor verify the audit. If the Payor audit confirms the report of the Payee's auditor, then the Payor will pay the deficiency and the cost of the Payee's audit within fifteen (15) days from the time Payee invoices for those fees and provides standard proof of the time and expenses incurred. 4. RELATIONSHIP OF THE PARTIES 4.1 The parties will be joint venturers only as to those activities that they jointly undertake for the AMR market as described in section 3 above; otherwise they shall be independent of each other, with full control over their respective activities without the need to account to the other, and independent contractors as to all work performed under separate agreements. Even though the parties will be joint ventureres as to the AMR market, neither party will have the right to bind the other in any way without the other party's express consent, and this Agreement shall not otherwise be construed to make any party the agent, assignee, employee, fiduciary, investor, joint venturer, partner, or representative of any other party. 5. TERM This Agreement will remain in force for perpetuity or until and unless otherwise mutually agreed or amended in writing by both parties. 6. NOTICES Source: LINK PLUS CORP, 8-K, 8/2/2005 All notices and communications required or permitted to be given under this Agreement will be deemed given after receipt when sent by United States Postal Service as registered or certified mail, postage prepaid, and addressed to the other party at the notice addresses set forth on the signature page (unless by such notice a different person or address shall have been designated) 7. ADDITIONAL PROVISIONS. 7.1 This Agreement may not be assigned in whole or in part by either party without prior written consent of the other. 7.2 All actions, cases, suits and proceedings in connection with this Agreement shall be brought in Maryland. All persons affected by this Agreement specifically consent to the personal jurisdiction of and venue in said courts. No action, case, suit or proceeding, regardless of form, arising out of or related to this Agreement, may be brought by either party more than one (1) year after the cause of action has arisen, or in the case of nonpayment, more than two (2) years from the date of the last payment. ALL ACTIONS, CASES, SUITS AND PROCEEDINGS SHALL BE HEARD WITHOUT A JURY. ALL PERSONS AFFECTED BY THIS AGREEMENT SPECIFICALLY WAIVE ALL RIGHT TO A TRIAL BY JURY AND SPECIFICALLY CONSENT TO THE PERSONAL JURISDICTION OF AND VENUE IN SAID COURTS. 7.3 If suit or action is instituted to enforce any of the terms of this Agreement, then the prevailing party shall be entitled to recover from the other party such sums as the Court may adjudge reasonable as attorney's fees at trial on or appeal of such suit or action, in addition to all other sums provided by law. 7.4 This Agreement shall be construed and governed in accordance with the laws of the State of Maryland regardless of the place or places of its physical execution and performance.
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Extract the exact clause related to "Expiration Date" from the excerpt above.

assistant: This Agreement will remain in force for perpetuity or until and unless otherwise mutually agreed or amended in writing by both parties.