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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Agreement. 1.44 "Person" shall mean any individual, corporation, partnership, limited liability company, association, joint-stock company, trust, unincorporated organization or other entity, or government or political subdivision thereof. 1.45 "Product" shall mean the product approved pursuant to New Drug Application (NDA) No. 210238, as such approval may be supplemented from time to time (including by way of supplemental new drug application (sNDA)), currently marketed as DOPTELET® (avatrombopag) in the Territory and shall include an authorized generic version of such Product. 1.46 "Product Labeling" shall mean the labels and other written, printed or graphic matter upon (a) any container or wrapper utilized with the Product or (b) any written material accompanying the Product, including Product package inserts, in each case as approved by the FDA. 1.47 "Product Materials" shall have the meaning set forth in Section 4.4.1(a). 1.48 "Product Training Materials" shall have the meaning set forth in Section 4.4.1(a). 1.49 "Quarterly Average Sales Force Size" shall have the meaning set forth in Section 4.2.2. 1.50 "Quarterly Minimum Details" for an applicable Calendar Quarter shall mean [***]. 1.51 "Regulatory Approval" shall mean any and all necessary approvals, licenses, registrations or authorizations from any Governmental Authority, in each case, necessary to commercialize the Product in the Territory. 1.52 "Retail Pharmacy" shall mean an outlet which dispenses the Product directly to a patient in a retail setting or through mail order services. 6 CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR PORTIONS OF THIS EXHIBIT. THE COPY FILED HEREWITH OMITS THE INFORMATION SUBJECT TO A CONFIDENTIALITY REQUEST. OMISSIONS ARE DESIGNATED [***]. A COMPLETE VERSION OF THIS EXHIBIT HAS BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION. Source: DOVA PHARMACEUTICALS INC., 10-Q, 11/8/2018 1.53 "Retail Net Sales" shall mean, for each SKU of the Product: (i) the number of units of such SKU of the Product shipped from Retail Pharmacies to patients based on prescriptions written by the Specialty in the Territory (as determined by data reported by data aggregator) or such other data source with which Dova enters into an agreement at its cost), MULTIPLIED BY (ii) the applicable WAC for such SKU of the Product for the applicable period, MULTIPLIED BY (iii) the Gross to Net Fraction for such SKU of the Product for the applicable period. 1.54 "Sales Representative" shall mean an individual employed and compensated by Valeant as a full-time employee as part of its sales forces and who engages in Detailing of the Designated Product (or the Alternate Product, as the case may be) in the Territory, and who is also trained with respect to the Product in accordance with this Agreement (including the Product Labeling and the use of the Promotional Materials) to deliver Details for the Product in the Field in the Territory. 1.55 "Senior Officer" shall mean, with respect to Dova, its President and Chief Executive Officer (or such officer's designee), and with respect to Valeant, its [***] (or such officer's designee). From time to time, each Party may change its Senior Officer by giving written notice to the other Party. 1.56 "Specialty" shall mean (i) Target Professionals with a primary or secondary specialty designation of Gastroenterology, Colorectal Surgery or Proctology (excluding any such Target Professionals with a primary or secondary specialty designation of Hepatology (including Transplant Hepatology), in each case, as determined by data reported by Dova's Third Party Data Source, subject to any adjustments determined pursuant to the process set out in Section 6.5, and (ii) all healthcare professionals with Nurse or Physician Assistant specialty designations affiliated with the Target Professionals described in subsection (i), as adjusted. 1.57 "Specialty Fraction" shall mean, for each SKU of the Product, a fraction (i) the numerator of which is the number of units of such SKU of the Product shipped from the Specialty Pharmacies or the Retail Pharmacies to patients based on prescriptions written by the Specialty in the Territory (as determined by data reported pursuant to agreements between Dova (or its Affiliates) and the Specialty Pharmacies or the data aggregators, applicable), and (ii) the denominator of which is the number of units of such SKU of the Product shipped from the Specialty Pharmacies or the Retail Pharmacies to all patients in the Territory (namely based on prescriptions written by the Specialty and outside the Specialty) (as determined by data reported pursuant to agreements between Dova (or its Affiliates) and the Specialty Pharmacies or the data aggregators, as applicable). 1.58 "Specialty Pharmacy Net Sales" shall mean, for each SKU of the Product: 7 CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR
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Extract the exact clause related to "Expiration Date" from the excerpt above.