MPL section 2.2, and patent grants on derivative works

John Cowan jcowan at
Fri Nov 22 18:15:56 UTC 2002

"Ravicher, Daniel (x2826)" scripsit:

> This brings up issue (a), in
> that if Developer, owner of patent claims covering A and B, modifies and
> distributes the software to cover A, then Developer has granted, under the
> OSL, a license to practice A with respect to the software as distributed by
> Developer or any derivative work thereof.  What Developer has most likely
> not done is grant a license to practice B in anything.  Therefore, a Third
> Party modifying the Developer's version of the software to now practice A
> and B, is likely not infringing the A claims, but is most probably
> infringing the B claims.
> So, to cover that situation, a license could hypothetically define Licensed
> Claims as "patent claims owned or controlled by the Licensor that are
> embodied in the Original Work as furnished by the Licensor or any Derivative
> Work made in compliance with this license."

That would make the Developer's patents worthless, one and all.  For an
unscrupulous person wishing to practice absolutely unrelated patent B would
simply have to add an utterly irrelevant module to the licensed software
that would otherwise infringe B and then claim a license from the Developer.
And the same for patent C, D, E, ...

I should add that I think software patents are stoopid.  But it's one thing
to ask companies to give away patent rights needed to use the program they
are also giving away, and quite another to ask them to implicitly surrender
all their patent rights, software-related or not.


What is the sound of Perl?  Is it not the       John Cowan
sound of a [Ww]all that people have stopped     jcowan at
banging their head against?  --Larry  
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