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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payments made under this Agreement, such recovery to be for the benefit of the Party bearing such withholding tax or value added tax. 4.9.1. Medical Device Tax. The party responsible for paying any applicable medical device excise tax pursuant to Section 4191 of the U.S. Internal Revenue Code or any successor thereto will be as determined under such tax provisions. If any, such medical device excise tax will be treated as a cost element to be included in COGS as referenced in Exhibit A. 4.10. Interest. Accrual and payment of interest shall not be deemed to excuse or cure breaches of contract arising from late payment or nonpayment. Cumulative with and not exclusive of any and all other available remedies, payments that are more than 30 days past due hereunder, and which are not otherwise subject to a good faith dispute, shall accrue interest, from the due date until paid, at an annual rate equal to the prime rate, as reported in The Wall Street Journal, Eastern U.S. Edition, on the date such payment is due, plus an additional 200 basis points (2%). 4.11. Currency. All invoices under this Agreement shall be paid in United States dollars. 5. Manufacturing and Quality Assurance 5.1. Manufacturing Conformance. Qualigen represents and warrants that it shall manufacture all Products in accordance with the applicable product specifications and all applicable federal, state and local laws, regulations, and guidelines. Qualigen represents and warrants that no Product delivered by Qualigen under this Agreement will be adulterated or misbranded within the meaning of 21 U.S.C. Sections 351-352, or within the meaning of any other applicable law as such laws are constituted and effective at the time of such shipment or delivery. Qualigen shall maintain appropriate certification status and compliance with the FDA's Quality System Regulation, the Directive of 27 October 1998 on In Vitro Diagnostic Medical Devices (IVDD) and/or all other applicable regulations. Upon request, Qualigen shall furnish to Sekisui any such information required to enable Sekisui to comply with all applicable regulations and standards that pertain to distributors for the Products. 5.2. Manufacturing Changes. Qualigen shall notify Sekisui in writing no less than 3 months prior to any material changes which affect (i) the form, fit or function of any Products, or (ii) the labeling or regulatory status of the Products in any of the Applicable Markets. 5.3. Manufacturing Site. During the Term, Qualigen shall manufacture all Products using Qualigen's facilities located in Carlsbad, California. Qualigen shall give at least six (6) months prior written notice to Sekisui of any proposed relocation of the manufacturing of any Product. Any new facility proposed to be used by Qualigen in manufacturing any Product shall be subject to a new and separate audit by Sekisui personnel in accordance with Quality Systems Regulations (QSR), as well as ISO 13485. 8 Source: RITTER PHARMACEUTICALS INC, S-4/A, 3/13/2020 5.4. Approved Supplier. It is acknowledged that Qualigen is an "Approved Supplier" as to Products manufactured at Qualigen's Carlsbad, California facility. As part of Sekisui's supplier approval program, Sekisui will have the option to perform an audit (applying Sekisui's standard supplier criteria for qualification as an "Approved Supplier") at Qualigen's Carlsbad, California manufacturing facility annually and at each relocated manufacturing facility at which Qualigen will manufacture the Products within sixty (60) days of Qualigen's notice to Sekisui of the relocation of such manufacturing facility. Within thirty (30) days after the completion of an audit, Sekisui shall inform Qualigen in writing of the results of such audit. If Qualigen does not pass such audit and the reasons for such failure can be remedied within a reasonable period of time (which shall not be less than sixty (60) days), then Sekisui shall provide Qualigen with a list of proposed remedial action items and a proposed timeframe within which to accomplish such action items. If Qualigen does not pass such audit and the reasons for such failure cannot be remedied within a reasonable period of time or Qualigen fails or elects not to complete any remedial actions reasonably suggested by Sekisui, then Sekisui's sole and exclusive remedy shall be to terminate this Agreement in accordance with the provisions of Section 14 of this Agreement, with such termination to be effective upon receipt of a termination notice by Qualigen sent by Sekisui at any time after the sixty day remedy period described in this Section 5.4 has passed. As scheduled, Sekisui may perform an audit during reasonable business hours to confirm ongoing compliance with the Quality System Regulations and
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.