Acceptable patent license for free software?

[Matthias-Christian Ott]

Simon Josefsson <simon at josefsson.org> wrote:

> Hi!  I'm writing guidelines for IETF document authors on how to achieve
> free software compatible copyright and patent licenses [1].  The
> copyright area is rather well understood, I think; pick any liberal
> license that is compatible with all (reasonable) free software licenses
> and you are done.
>
> However, the patent license area seems less clear to me.
>
> Does anyone have some references to any patent license that have been
> deemed acceptable to some free software projects?
>
> Going further, is there some kind of patent license that free software
> would _prefer_ (as opposed to just _accept_)?
>
> To give a concrete example of what I'm thinking of:
>
> There is one patent license in <https://datatracker.ietf.org/ipr/942/>:
>
>   Subject to the terms and conditions of this License, Google hereby
>   grants to You a perpetual, worldwide, non-exclusive, no-charge,
>   royalty-free, irrevocable (except as stated in this License) patent
>   license for patents necessarily infringed by implementation (in whole
>   or in part) of this specification. If You institute patent litigation
>   against any entity (including a cross-claim or counterclaim in a
>   lawsuit) alleging that the implementation of the specification
>   constitutes direct or contributory patent infringement, then any
>   patent licenses for the specification granted to You under this
>   License shall terminate as of the date such litigation is filed.
>
> This patent license is a reciprocal license, but is fairly limited in
> scope.
>
> Would that be acceptable to free software projects?

In my opinion you should ask an expert lawyer, because copyright and
patent right may be different in different countries. Or are you just
writing for the USA?

Regards
Matthias-Christian