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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Developer's expressly granted rights under this Agreement, Developer acknowledges and agrees that DSS shall own all right, title, and interest in and to the Technology, the Improvements, its Intellectual Property, and all future derivative works derived therefrom or developed hereunder. Developer agrees that it will not at any time (i) do or cause to be done any act or thing contesting or in any way impairing any part of such right, title and interest or (ii) represent, expressly or by implication that it has any right, title or interest in or to any of the foregoing other than as expressly set forth herein. 3.2. Developer hereby acknowledges DSS's claim of sole ownership of the Technology, the Improvements, and all associated goodwill. Nothing in this Agreement or in the performance thereof, or that might otherwise be implied by law, shall operate to grant Developer any right, title, or interest in or to the Technology or the Improvements. Developer hereby assigns and shall assign in the future to DSS all rights it may acquire by operation of law or otherwise in the Technology or Improvements, along with the goodwill associated therewith. DSS shall have the sole right to, and in its sole discretion may, commence, prosecute or defend, and control any legal action concerning the Technology and Improvements. Developer may not contest the validity of, by act or omission jeopardize, or take any action inconsistent with, DSS's ownership rights or goodwill in the Technology or Improvements, including any attempted registration of the Technology or Improvements in Hong Kong or in any other legal jurisdiction, or any attempts to license the same to any unauthorized third Person. 4. Definitions. For purposes of this Agreement, the following capitalized terms shall have the meanings set forth below. "Improvements" shall mean technical improvements, modifications or enhancements relating to the Technology that are developed by the Developer pursuant to this Agreement. "Intellectual Property" shall mean, but shall not be limited to, all of DSS's (i) issued and pending patents, trademarks, trade names, service marks, designs, logos, and copyrights, and all pending applications for registration thereof; (ii) know-how, inventions, improvements, methods, operation manuals and procedures, trade secrets, technical information, formulas; (iii) computer software and programs, and related documentation, updates, and data, whether in object or source code form, and (vi) other similar proprietary and intellectual rights, whether or not registered. "Person" shall mean any individual, corporation, partnership, limited liability company, association, trust or any other entity or organization of any kind or character, including a governmental authority or agency. "Technology" shall collectively mean (i) DSS's proprietary AuthentiGuard® technology (including DSS's related patents and patent applications, inventions, software, trademarks, trade names, service marks, technology marks, designs, logos, copyrights, know-how, trade secrets and any other DSS owned intellectual property relating thereto), consisting of a unique application of the AuthentiGuard® patent coupled with next generation technology and software which enables and end-to-end brand protection solution for product authentication, counterfeit deterrence and data tracking via embedded customized technology marks with hidden codes placed in products which can be read an authenticated via an application loaded on various devices along with necessary hardware and DSS's portal, (ii) DSS's Prism Viewer technology comprised of a custom covert Prism image imbedded in a customer's products that is viewed and authenticated through the use of DSS's propriety smart phone application, and (iii) DSS's AuthentiSite technology suite comprised of an embedded digital Prism image coupled with a cloud-based security server and a smart phone verification application for website authentication. 5. Confidentiality; Non-Disclosure. The parties acknowledge that they have entered into that certain Mutual Non-Disclosure Agreement dated as of January 18, 2018 (the "NDA"), a copy of which is attached hereto as Exhibit A. The terms of the NDA shall be deemed to be incorporated by reference into this Agreement, mutatis mutandis. During the Term of this Agreement and thereafter for a period of five (5) years, the parties shall be bound by all of the protective terms and conditions of the NDA. 6. Developer Liability. 6.1. Developer Liability for Damages. Developer shall be fully liable, without limitation, for money damages resulting from its improper or unauthorized use, modification, alteration, licensing or transfer of the Technology or Improvements, or resulting from its failure to provide functional and merchantable Improvements hereunder, which failure shall be deemed a material breach of this Agreement by Developer. 2 Source: HF ENTERPRISES INC., S-1, 12/23/2019 7. DSS's Representations and Warranties. 7.1. Power and Authority. DSS represents and warrants that it has the right,
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Extract the exact clause related to "Expiration Date" from the excerpt above.