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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to have, other programs that may compete for resources that may be expended in the Promotion of the Product. Except as otherwise set forth in Section 2.3 with respect to Competing Products, nothing in this Agreement shall limit or restrict the right of MMT or its Affiliates to develop, make regulatory filings, obtain regulatory approvals with respect to, or to Commercialize any product that is not the Product or, with respect to MMT only, a Competing Product or to engage in any business or other activity. 4.3 Customer Contracts. (a) Subject to Section 2.4 and Section 4.3(b), MMT shall serve as the primary contracting party [***]. (b) [***]. 14 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 4.4 Regulatory Matters. (a) Subject to Sections 4.4(b) and (c) each Party, at its sole cost and expense, will be responsible for obtaining all regulatory authorizations, permits, licenses, and approvals required to carry out its obligations under this Agreement. (b) [***]. (c) MMT will provide SIGA with final copies of any marketing, advertising, promotional materials and other communications developed pursuant Section 4.1(c), and as soon as reasonably practicable thereafter, SIGA will be responsible for submitting on MMT's behalf such materials or other communications to seek to obtain any approvals necessary under applicable Law for the use of such materials in the Territory. (d) MMT will promptly notify SIGA, and shall provide SIGA with a copy, of any information it receives regarding any threatened or pending action, inspection or communication by or from any Third Party, including a Regulatory Authority, which may affect the regulatory status of the Product and will reasonably cooperate with SIGA in its response thereto. MMT may choose not to disclose communications, other than communications from Regulatory Authorities, to the extent that MMT's counsel reasonably believes that such disclosure to SIGA could violate applicable privacy laws or have a significant adverse impact on MMT's legal position or defense (including the loss of attorney-client privilege), in which case MMT shall promptly notify SIGA that it is exercising its right not to disclose. 4.5 Discontinued Countries. For clarity, notwithstanding anything to the contrary set forth herein, upon the designation of a country as a "Discontinued Country" under this Agreement, SIGA shall have the right to Promote the Product in the Discontinued Country at its sole discretion and cost. Upon designation of a country as a "Discontinued Country" in accordance with Section 4.2, MMT shall immediately cease all Promotional efforts related to the Product in such country, and SIGA shall have the sole right to Promote the Product in such Discontinued Country during and after the Term. ARTICLE 5 FORECASTING AND ORDERING 5.1 Product Forecasts. (a) [***]. (b) [***]. 5.2 Purchase Orders. (a) [***]. [***]. [***]. 15 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 5.3 Delivery. [***]. 5.4 Supply Limitation. [***]. 5.5 Supply Penalties. [***]. 5.6 Adverse Event Reporting. MMT or its Affiliates will reasonably cooperate with SIGA to meet applicable pharmacovigilance and safety reporting requirements and in the event of a Product recall. To facilitate pharmacovigilance and safety reporting, the Parties agree that they will follow the procedures described in Schedule 3 Safety Reporting Requirements, which may be amended from time-to-time, to ensure that adverse event and other safety information is identified, reviewed, and reported in a manner that will permit SIGA to comply with applicable Laws, including any reporting requirements with any applicable Regulatory Authority. ARTICLE 6 PAYMENTS 6.1 Promotion Fee. (a) In consideration for the services provided by MMT hereunder, commencing with the First Commercial Sale of the Product in the Territory, MMT shall be entitled to retain a fee (the "Promotion Fee") 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
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.