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:
"""
13.16 Further Actions and Documents. 47 13.17 Certain Conventions. 47 13.18 Counterparts. 47 iii 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 CO-PROMOTION AGREEMENT This Co-Promotion Agreement (this "Agreement") is entered into and dated as of September 26, 2018 (the "Effective Date") by and between Dova Pharmaceuticals, Inc., a Delaware corporation ("Dova"), and Valeant Pharmaceuticals North America LLC, a Delaware limited liability company ("Valeant"). Dova and Valeant are each referred to individually as a "Party" and together as the "Parties". RECITALS WHEREAS, Dova has developed and has rights to market and sell the Product (as defined below) in the Territory; WHEREAS, the Parties believe that it would be mutually beneficial to collaborate on promotional activities for the Product and, accordingly, Dova desires that Valeant conduct certain promotional activities, and Valeant desires to conduct such activities, for the Product in the Territory; NOW, THEREFORE, in consideration of the following mutual promises and obligations, and for other good and valuable consideration the adequacy and sufficiency of which are hereby acknowledged, the Parties agree as follows: 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 ARTICLE 1 DEFINITIONS 1.1 "Act" shall mean the Federal Food, Drug and Cosmetic Act, 21 U.S.C. § 301 et seq., as it may be amended from time to time, and the regulations promulgated thereunder. 1.2 "Adverse Event" shall mean any untoward medical occurrence in a patient or clinical investigation subject who is administered the Product, but which does not necessarily have a causal relationship with the treatment for which the Product is used. An "Adverse Event" can include any unfavorable and unintended sign (including an abnormal laboratory finding), symptom or disease temporally associated with the use of the Product, whether or not related to the Product. A pre-existing condition that worsened in severity after administration of the Product would be considered an "Adverse Event". 1.3 "Affiliate" shall mean, with respect to any Person, any other Person that directly or indirectly controls, is controlled by or is under common control with such Person. A Person shall be deemed to control another Person if such Person possesses the power to direct or cause the direction of the management, business and policies of such Person, whether through the ownership of fifty percent (50%) or more (or such lesser percentage which is the maximum allowed to be owned by a foreign corporation in a particular jurisdiction) of the voting securities of such Person, by contract or otherwise. 1.4 "Agreement" shall have the meaning set forth in the preamble to this Agreement. 1.5 "Alliance Managers" shall have the meaning set forth in Section 4.1.4. 1.6 "Alternate Product" shall mean a pharmaceutical product that is commercialized by Valeant or its Affiliates in the Territory and that is part of the Salix business segment of Valeant's parent company, Bausch Health Companies, Inc. (or, in the event that such business segments are restructured, that is part of the Salix business unit), and which product is complementary to the Product with regard to Target Professionals in the Specialty. 1.7 "Applicable Laws" shall mean all applicable statutes, ordinances, regulations, codes, rules, or orders of any kind whatsoever of any Governmental Authority in the Territory pertaining to any of the activities and obligations contemplated by this Agreement, including, as applicable, the Act, the Generic Drug Enforcement Act of 1992 (21 U.S.C. § 335a et seq.), the Anti- Kickback Statute (42 U.S.C. § 1320a-7b et seq.), the Health Insurance Portability and Accountability Act of 1996, the Federal False Claims Act (31 U.S.C. §§ 3729-3733) (and applicable state false claims acts), the Physician Payments Sunshine Act, the Code, the Department of Health and Human Services Office of Inspector General Compliance Program Guidance for Pharmaceutical Manufacturers, released April 2003, the Antifraud and Abuse Amendment to the Social Security Act, the American Medical Association guidelines on gifts to physicians, generally accepted standards of good clinical practices adopted by current FDA regulations, as well as any state laws and regulations (i) impacting the promotion of pharmaceutical products, (ii) governing the provision of meals and other
"""

Extract the exact clause related to "Expiration Date" from the excerpt above.