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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of: (i) [***] of the Yearly Collected Revenue of the Product in the Territory in each Calendar Year during the Term if the aggregate Net Product Sales Amounts for such Calendar Year are equal to or below [***]; and (ii) [***] of the Yearly Collected Revenue of the Product in the Territory in each Calendar Year during the Term if the aggregate Net Product Sales Amounts for such Calendar Year exceed [***]. (b) In satisfaction of MMT's rights to the Promotion Fee, MMT shall retain from each payment to SIGA of the Quarterly Collected Revenue an amount equal to (i) [***] of the Quarterly Collected Revenue in the Territory during such Calendar Quarter so long as the total Net Product Sales Amounts in the Territory during the relevant Calendar Year are equal to or below [***] and (ii) [***] of the Quarterly Collected Revenue in the Territory during such Calendar Quarter where the total Net Product Sales Amounts in the Territory during the relevant Calendar Year exceeds [***] and (iii) any Credit Amounts. If the Net Product Sales Amounts in the Territory exceeds [***] during any Calendar Year after any Quarterly Payment has been made, MMT shall automatically accrue a credit of [***] (the "Credit Amount") (representing the additional [***] fee that MMT would be entitled to receive with respect to the first [***] of the Quarterly Collected Revenue as a result of total Net Product Sales Amounts in the relevant Calendar Year having [***]), which Credit Amount will be deducted from future payments of Quarterly Collected Revenue to SIGA until the full Credit Amount is retained by MMT. 16 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 6.2 Payments. (a) Within [***] days after the conclusion of each Calendar Quarter to occur during the Term, commencing with the First Commercial Sale of the Product in the Field in the Territory, MMT shall deliver to SIGA a written report containing the following information (each a "Quarterly Report"): [***]. All such reports shall be considered Confidential Information of MMT. Concurrent with the delivery of the applicable Quarterly Report, MMT shall pay to SIGA in Dollars by wire transfer of immediately available funds into an account designated by SIGA in writing in advance of such payment the net result of Quarterly Collected Revenues, minus the corresponding Promotion Fee, and minus any applicable Credit Amount for such Calendar Quarter (all amounts as calculated in the Quarterly Report, and the payment of the net result being a "Quarterly Payment"). (b) Upon the expiration or termination of this Agreement, MMT shall submit a final written report covering the time period between the date of the last Quarterly Report submitted by MMT and the date of expiration or termination of this Agreement (the "Final Report"). The Final Report shall contain all information required to be included in a Quarterly Report with respect to the time period between the conclusion of the most recent Calendar Quarter and the date of expiration or termination of this Agreement. If MMT owes any outstanding amounts to SIGA as calculated pursuant to such Final Report, then MMT shall pay to SIGA in Dollars such outstanding amounts by wire transfer of immediately available funds into an account designated by SIGA in writing in advance of such payment within [***] days after delivery of the Final Report. If SIGA owes any amounts relating to any portion of any outstanding Credit Amounts or otherwise, then SIGA shall pay such outstanding amounts to MMT within [***] days after delivery of the Final Report. 6.3 Currency. All sums due under this Agreement shall be payable in Dollars. Any amounts in currencies other than Dollars shall, for purposes of determining Net Product Sales Amounts or Quarterly Collected Revenue, be converted to Dollars using the [***]. Once the Net Product Sales Amount or Quarterly Collected Revenue payable in respect of a particular Calendar Quarter has been converted into Dollars, such amount of Dollars shall be used for the purpose of calculating the total Net Product Sales Amount and Quarterly Collected Revenue during the Calendar Year that includes such Calendar Quarter. 6.4 Records. MMT will keep (and will ensure that its Affiliates and sublicensees keep) such records as are required to determine, in accordance with U.S. generally accepted accounting principles or international financial reporting standards, as applicable, and this Agreement and the sums or credits due under this Agreement, including Net Product Sales Amounts. MMT will retain all such books, records and accounts until the later of (a) [***] after the
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.