---
key: ms-patent-promise-mono
short_name: Microsoft Patent Promise for Mono
name: Microsoft Patent Promise for Mono
category: Patent License
owner: Microsoft
homepage_url: https://www.mono-project.com/docs/faq/licensing/
spdx_license_key: LicenseRef-scancode-ms-patent-promise-mono
text_urls:
    - https://github.com/mono/mono/blob/main/PATENTS.TXT
---

Microsoft Patent Promise for Mono

Microsoft Corporation and its affiliates (“Microsoft”) promise not to
assert any Applicable Patents against you for making, using, selling,
offering for sale, importing, or distributing Mono.

If you file, maintain, or voluntarily participate in any claim in a
lawsuit alleging direct or contributory patent infringement by Mono,
or inducement of patent infringement by Mono, then your rights under
this promise will automatically terminate.

This promise is not an assurance that (i) any Applicable Patents are
valid or enforceable or (ii) Mono does not infringe patents or other
intellectual property rights of any third party. No rights except
those expressly stated in this promise are granted, waived or received
by Microsoft, whether by implication, exhaustion, estoppel or
otherwise. This is a personal promise directly from Microsoft to you,
and you agree as a condition of benefitting from it that no Microsoft
rights are received from suppliers, distributors, or otherwise in
connection with this promise.

Definitions:

“Mono” means those portions of the software development technology, as
originally distributed by Xamarin, Inc. or the .NET Foundation under
the name “Mono,” that implement .NET Framework Functionality, provided
that such portions at a minimum implement all of the required parts of
the mandatory provisions of Standard ECMA-335 – Common Language
Infrastructure (CLI).

“.NET Framework Functionality” means any functionality in Microsoft’s
.NET Framework as described in Microsoft’s API documentation on
Microsoft’s MSDN website, including the functionality in
Windowsbase.dll, but excluding all other functionality in the Windows
Presentation Foundation component of .NET Framework.

“Applicable Patents” are those patent claims, currently owned by
Microsoft and acquired in the future, that are necessarily infringed
by Mono. For clarity, Applicable Patents do not include any patent
claims that are infringed (x) by any underlying or enabling technology
that may be used, combined, or distributed in connection with Mono
(such as hardware, operating systems, or applications that run on
Mono), (y) only as a consequence of modification of Mono, or (z) only
by the combination of Mono with third party code.