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:
"""
of this Agreement or the Supply Agreement arising from or attributable to any acts, events, non-happenings, omissions or accidents beyond the reasonable control of the Party to perform and in particular but without limiting the generality thereof shall include strikes and labor disturbances, lock-outs, industrial action, civil commotion, riot, invasion, war, threat of or preparation for war, terrorist activity, fire, explosion, storm, flood, earthquake, subsidence, epidemic or other natural physical disaster, impossibility of the use of railways, shipping, aircraft, motor transport, or other means of public or private transport, failure or suspension of utilities, unavailability, shortage or interruption in the supply of raw material, and political interference with the normal operation of either Party; "Improvements" Means any discovery, development, improvement, know-how or patent relating to the Product generated, conceived, reduced to practice or otherwise created during the Term by PPI or EKR (or any Affiliate of PPI or EKR); "Joint Improvements" Means any Improvements generated, conceived, reduced to practice or other created jointly by EKR and PPI or their Affiliates. "Known In-Channel Product Units" Shall have the meaning set forth in Section 3.19 hereof; -8- "Marketing Authorization" Means the new drug application ("NDA") and all other necessary regulatory and governmental approvals by a Regulatory Authority or other governmental body required to market and sell the Product in any country of the Territory, including, but not limited to, those set forth on Schedule V hereto; "Marketing Plan" Means the plan for the marketing, distribution and sale of the Product in the Territory submitted to the Commercialization Committee in accordance with Section 5.4; -9- "Net Sales" Means total gross sales of Product invoiced by EKR, its Affiliates and sub-distributors in arms length sales to Third Parties, less the following amounts actually incurred, deducted, accrued or allowed: (i) transport, freight and insurance costs which are separately stated; (ii) sales and excise taxes and duties; (iii) normal and customary trade, quantity and cash discounts, rebates and chargebacks; (iv) amounts repaid or credited for properly rejected, returned or recalled goods or resulting from retroactive price adjustments related to the Product; (v) amounts incurred or resulting from government (or an agency thereof) mandated or managed care or other rebate programs now existing or implemented hereafter; (vi) any other identifiable amounts included in gross sales of the Product that were or ultimately will be credited and that are substantially similar to those listed hereinabove; and (vii) any other deductions allowed by GAAP which effectively reduce the net selling price of Product; "PPI Improvement" Means any Improvement generated, conceived, reduced to practice or otherwise created during the Term by PPI or any of its Affiliates; -10- "PPI IP" Means the Copyrights, PPI Know-How, PPI Patents and PPI Improvements; and PPI's interest in Joint Improvements; "PPI Know-How" Means all information, procedures, instructions, techniques, data, technical information, knowledge and experience (including, without limitation, toxicological, pharmaceutical, clinical, non-clinical and medical data, health registration data and marketing data), designs, dossiers (including, without limitation, manufacturing assay and quality control dossiers) manufacturing formulae, processing specifications, sales and marketing materials and technology relating to the Product; "PPI Patents" Means those patents set out in Schedule I which cover the Products and such other patents as PPI may include from time to time, including additions, divisions, confirmations, continuations-in-part, substitutions, re-issues, re-examinations, extensions, registrations, patent terms extensions, supplementary protection certificates and renewals of any of the above or any other patents owned or licensed by PPI subsequent to the Effective Date which cover the Products or any Improvements; -11- "Product(s)" Means: (i) DepoDur Injectible Liposomal Epidural [**] mg/ml [**]; (ii) DepoDur Injectible Liposomal Epidural [**] mg/[**] ml [**]; (iii) such other presentations and dosages which hereafter receive Marketing Authorization in any country of the Territory; in each case for epidural administration presented in Vials or other approved vessels, appropriately packaged and labeled for sale to end users and (iv) any and all Improvements of the items listed in clauses (i) through (iii). "Promotional Materials" Means promotional, sales, marketing, educational and training materials which are necessary to support the marketing of the Products; "Quarter" Means a three month period ending on the last day of March, June, September or December in any Calendar Year; "Regulatory Authority" Means any competent regulatory authority or other governmental body (for example, but not by way of limitation the FDA and DEA) responsible for granting a Marketing Authorization in the Territory; "Royalty Cap" Shall have the meaning set forth in Section 6.4; "Supply Agreement" Means: (i) with respect to periods between the Effective
"""

Extract the exact clause related to "Joint Ip Ownership" from the excerpt above.