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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their Affiliates. For purposes of clarity, the foregoing does not prevent Conformis from granting any license, release, covenant not to sue or other immunity to any third party under any Patents, including any such immunity that would authorize manufacture, use or sale of Patient-Specific Instrumentation for Off-The-Shelf Knee Implants outside the Buyer Field. ARTICLE V INTELLECTUAL PROPERTY 5.1 Inventions. (a) Inventorship of all Inventions developed by either Party, or both Parties, in the performance of the R&D Program, shall be determined in accordance with the inventorship laws of the United States, even to the extent such Invention is not pursued in patent applications. (b) All right, title and interest in and to the Improved Stryker Background IP will vest solely in Stryker. Conformis agrees to assign and hereby assigns to Stryker all right, title and interest in and to all Improved Stryker Background IP in which ownership in same has vested in 11 Source: CONFORMIS INC, 10-Q, 11/1/2019 Conformis by operation of law or by assignment by its employees or consultants; and to facilitate such assignment to Stryker, Conformis agrees (i) to regularly ensure that its employees and consultants timely make any appropriate assignments to it of that which constitutes Improved Stryker Background IP, and (ii) at Stryker's reasonable request, to execute and have its employees and consultants execute, as necessary, all assignments and any other documentation necessary to perfect title in Stryker of such Improved Stryker Background IP. (c) All right, title and interest in and to the Improved Conformis Background IP and KIB Product IP ("Joint IP") shall be owned jointly by the Parties. Subject to the limitations set forth in this Agreement, the Joint IP may be used freely by either Party or its Affiliates and licensed to Third Parties by Conformis and its Affiliates, on the one hand, outside of the Buyer Field or by Stryker and its Affiliates, on the other hand, within the Buyer Field, in each case, without the consent of, or duty to account to or notify, the other Party, but, except with respect to external licenses of the Improved Conformis Background IP by Conformis or its Affiliates to Third Parties, any external Third Party license shall be governed in accordance with the last sentence of Section 4.3(c) of the APA. Each Party to whom ownership is to vest in Joint IP by operation of law or by assignment by its employees or Agents agrees to assign and hereby assigns to the other Party an undivided one-half right, title and interest in and to all Joint IP; and to facilitate such assignment, the Party possessing such ownership agrees (i) to regularly ensure that its employees and consultants timely make any appropriate assignments to it; and (ii) at the other Party's reasonable request, to execute and have its employees and consultants execute, as necessary, all assignments and any other documentation to perfect the undivided one-half right, title and interest in and to the other Party of such Joint IP. (d) Notwithstanding anything to the contrary, the foregoing does not constitute either (1) the grant by Conformis to Stryker of any license or immunity of any kind with respect to the Conformis Background IP or Conformis Foreground IP, regardless of the extent to which the Joint IP constitutes improvements to the Conformis Background IP or Conformis Foreground IP, (2) the grant by Stryker to Conformis of any license or immunity of any kind with respect to the Stryker Background IP, or (3) the grant by either Party of any license or immunity of any kind under any Intellectual Property rights owned by such Party, regardless of whether the exploitation of the Joint IP would infringe such Intellectual Property rights. Neither Party shall assign a partial interest in 12 Source: CONFORMIS INC, 10-Q, 11/1/2019 the Joint IP or Joint IP Rights to any Affiliate or Third Party (i.e., neither Party shall create any additional joint owners of the Joint IP), but each Party may assign all of its right, title and interest in and to the Joint IP and Joint IP Rights to an Affiliate or Third Party pursuant to and in accordance with Section 10.2. (e) Conformis shall promptly disclose to Stryker all (i) Improved Stryker Background IP, and (ii) Joint IP. Stryker shall promptly disclose to Conformis all Joint IP. (f) To the extent required and for the avoidance of doubt, Stryker hereby grants Conformis, and Conformis hereby accepts, a non-exclusive license to the Stryker Background IP and Improved Stryker Background IP solely
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Extract the exact clause related to "Ip Ownership Assignment" from the excerpt above.

assistant: Each Party to whom ownership is to vest in Joint IP by operation of law or by assignment by its employees or Agents agrees to assign and hereby assigns to the other Party an undivided one-half right, title and interest in and to all Joint IP; and to facilitate such assignment, the Party possessing such ownership agrees (i) to regularly ensure that its employees and consultants timely make any appropriate assignments to it; and (ii) at the other Party's reasonable request, to execute and have its employees and consultants execute, as necessary, all assignments and any other documentation to perfect the undivided one-half right, title and interest in and to the other Party of such Joint IP.