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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the Field within the Territory in accordance with the then-current Business Plan; provided that MMT shall not Promote any Product within any Restricted Market or Discontinued Country. (c) MMT shall conduct all Promotion activities in accordance with applicable Laws, Pfizer policies and practices regarding advertising, marketing, promotional and other Product-specific communications, and the terms of this Agreement. MMT may prepare marketing, advertising, promotional materials and other communications relating to the Product for Promotion use in the Field in the Territory. All such materials shall be truthful and non-misleading, and in compliance with applicable Laws, and subject to review by SIGA through the JSC; provided that the final decision to use any approved materials will be at the sole discretion of MMT. (d) Subject to Section 4.2, SIGA shall provide reasonable assistance to MMT with respect to MMT's conduct of Promotion activities with respect to the Product in the Field in the Territory as specifically set forth in the Business Plan, including providing responses to medical inquiries communicated to MMT's sales representatives or other external-facing MMT representatives or received by MMT by letter, phone call or email or other means of communication, at MMT's sole cost and expense; provided, however, SIGA shall solely be responsible for the costs and expenses associated with the response to any medical inquiries. 13 Source: SIGA TECHNOLOGIES INC, 8-K, 6/3/2019 (e) MMT will provide appropriate (as determined by MMT in its sole discretion) training (including regarding compliance with applicable Laws) of the MMT Promotion Personnel who will be communicating with potential customers about the Product. (f) Subject to Section 13.6, MMT may not use any subcontractor that is not a Permitted Sublicensee to fulfill its obligations under this Agreement. 4.2 Diligence. Notwithstanding anything herein to the contrary, MMT's commitment to use Commercially Reasonable Efforts as set forth herein shall not preclude the suspension or discontinuance of the Promotion of the Product in the Field in a country within the Territory, if reasonably appropriate, based on the application of Commercially Reasonable Efforts with respect to the Promotion of the Product in such country. If MMT does not document in the Business Plan [***]the Product in the Field in a country in the Territory ("[***]") for a period of either (i) [***] calendar months after the Effective Date for Tier 1 Countries, (ii) [***] calendar months after the Effective Date for Tier 2 Countries or (iii) [***] calendar months after the Effective Date for Tier 3 Countries (each such time period set forth in (i)-(iii) being a "Tier Period"), then no later than [***] Business Days after the expiration the applicable Tier Period for such country, SIGA may provide MMT with written notice [***] non-[***] (a "Non-[***] Notice") in such country, and upon MMT's receipt of such Non-[***] Notice, such country shall be deemed to be a "Discontinued Country" for purposes of this Agreement. If [***], SIGA shall have the right to designate the applicable country as a Discontinued Country at any time thereafter as long as the relevant Tier Period [***] for the country has been met at the time of the Non-[***] Notice. SIGA hereby acknowledges and agrees that MMT and its Affiliates make (and have made) no representation or warranty, either express or implied, at law or in equity, that it will be able to successfully achieve any amount of Net Product Sales Amount, and SIGA specifically disclaims that it is relying upon or has relied upon any such representations or warranties that may have been made by any individual or entity. SIGA acknowledges and agrees that MMT and its Affiliates have, and will continue 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
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Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.