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:
"""
Schedule B. (f) OEM Technology. Notwithstanding the foregoing, the Parties acknowledge and agree that this Section 3.01 does not grant any rights or licenses to any OEM Technology, which is subject to certain separate agreements between the Parties, and to the 6 Source: CERENCE INC., 8-K, 10/2/2019 extent there is a conflict between this Agreement and such separate agreements, such separate agreements shall control. (g) Sublicenses. The licenses granted in Sections 3.01(a), (b) and (c) to the SpinCo Group include the right to grant sublicenses within the scope of such licenses only to members of the SpinCo Group and, without any further right to sublicense, to their respective (i) contractors, distributors, manufacturers and resellers, in each case solely for the benefit of the SpinCo Business, and (ii) end users and customers, in each case solely in connection with the use of products and services of the SpinCo Business. Notwithstanding the forgoing, subject to Section 3.02(b) and ARTICLE VI, members of the SpinCo Group may only sublicense the Nuance Shared Technology Assets pursuant to terms and conditions as protective as those under which it licenses its own Technology of a similar nature and value, and in any event terms and conditions that provide for commercially reasonable protection for the source code, structure and other confidential and proprietary elements of the Nuance Shared Technology Assets. The SpinCo Group shall remain liable for any breach or default of the applicable terms and conditions of this Agreement by any of its sublicensees. Section 3.02. Other Covenants. (a) SpinCo hereby acknowledges Nuance's right, title and interest in and to the Nuance IP. SpinCo agrees that it will not (i) oppose, challenge, petition to cancel, contest or threaten in any way, or assist another party in opposing, challenging, petitioning to cancel, contesting or threatening in any way, any application or registration by Nuance or its Affiliates or their respective licensees for any Nuance IP, (ii) engage in any act, or purposefully omit to perform any act, that impairs or adversely affects the rights of Nuance or any member of the Nuance Group in and to any Nuance IP or (iii) apply for any registration (including federal, state and national registrations) with respect to the Nuance IP. (b) With respect to the Nuance Shared Technology Assets, SpinCo agrees that it will not (i) engage in any act, or purposefully omit to perform any act, that impairs or adversely affects the rights of Nuance or any member of the Nuance Group in and to any Nuance Shared Technology Assets, (ii) use the Nuance Shared Technology Assets on a service bureau, time sharing or similar basis, or for the benefit of any other Person, (iii) remove any proprietary markings in the Nuance Shared Technology Assets, (iv) incorporate or otherwise combine or integrate any open source software with or into the Nuance Shared Technology Assets such that the Nuance Shared Technology Assets, or any part thereof, becomes subject to any "open source," "copyleft" or similar type of license terms (including, without limitation, any license that is or was recognized as an open source software license by the Open Source Initiative), (v) reverse engineer, reverse assemble or decompile the Nuance Shared Technology Assets or any software component of the Nuance Shared Technology Assets or (vi) disclose, distribute or otherwise provide or permit access to source code of any Nuance Shared 7 Source: CERENCE INC., 8-K, 10/2/2019 Technology Assets other than to commercial source code escrow providers who are only permitted to make such source code available to third parties that have entered into an escrow agreement with a member of the SpinCo Group and escrow provider. ARTICLE IV LICENSES AND COVENANTS FROM SPINCO TO NUANCE Section 4.01. License Grants. (a) Patents. Subject to the terms and conditions of this Agreement, as of the Distribution Date, SpinCo hereby grants to Nuance and the members of the Nuance Group a worldwide, non-exclusive, fully paid-up, perpetual and irrevocable, transferable (subject to ARTICLE VIII), sublicensable (subject to Section 4.01(g)) license under the SpinCo Patents, solely to the extent that claims of the SpinCo Patents cover products or services of the Nuance Business in the Nuance Field of Use, together with natural extensions and evolutions thereof, in each case to make, have made use, sell, offer for sale, import and otherwise exploit such products and services, together with natural extensions and evolutions thereof. (b) Technology. Subject to the terms and conditions of this Agreement, as of the Distribution Date, SpinCo hereby grants to Nuance and the
"""

Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.

assistant: Subject to the terms and conditions of this Agreement, as of the Distribution Date, SpinCo hereby grants to Nuance and the members of the Nuance Group a worldwide, non-exclusive, fully paid-up, perpetual and irrevocable, transferable (subject to ARTICLE VIII), sublicensable (subject to Section 4.01(g)) license under the SpinCo Patents, solely to the extent that claims of the SpinCo Patents cover products or services of the Nuance Business in the Nuance Field of Use, together with natural extensions and evolutions thereof, in each case to make, have made use, sell, offer for sale, import and otherwise exploit such products and services, together with natural extensions and evolutions thereof.