license with patent grants appropriate for specifications?

[Bob Scheifler]

> The compromise I try to reach with patent owners in the context of industry
> standards is that 
> (1) patent owners may choose to limit the scope of their patent license
> grants to compliant implementations, and 
> (2) those patent licenses may not restrict anyone from creating and
> distributing non-compliant implementations.
> 
> As to the specification copyright license, it is consistent with open source
> principles if it grants you permission to create derivative works of the
> specification.

So, is it reasonable to take the following approach:
  - issue the specification itself under an existing open source license,
    one that in and of itself does not grant any patent rights with respect
    to implementations of the spec
  - provide separately a patent-only license that grants patent rights
    to compliant implementations of that specification (or broader if
    one wishes)
rather than trying to bundle these together into a single open source
license? The patent-only license, not being a source license at all,
presumably does not have to be an open source license.

- Bob