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Re: Answers to your questions about W3C patent policy



bruce@perens.com (Bruce Perens) writes:
> From: James Antill <james@and.org>
> From Bruce:
>> > The code that makes use of
>> > the patented principle must be under the MIT license, which allows a
>> > scope-limited patent license. That may be linked into GPL code and
>> > distributed.
>> 
>>  How does this work?
>>  Say I have "xmms", which is GPL code that I didn't write ... and I
>> want to implement some w3c std. that contains one of these patents. So
>> I do the code as an MIT license, but I'm going to have to link it to
>> the GPL'd code ... it's going to be a _derivative work_ ... so the
>> code is basically GPL, no matter what I put at the top of the file.
>
> The GPL terms on linking are that all parts of the derivative work must be
> under a license with _no_additional_restrictions_ on top of those in the
> GPL. The GPL does not prevent you from _removing_restrictions_, as long
> as you are the copyright holder on the portion of the code in question.

I don't see how that can possibly coexist with this sentence of the
GPL, section 7:

: if a patent license would not permit royalty-free redistribution of
: the Program by all those who receive copies directly or indirectly
: through you, then the only way you could satisfy both it and this
: License would be to refrain entirely from distribution of the Program.

The recipient of the program (which combines a GPL'd framework
with a patent-encumbered MIT library) will be able to use the program
to implement the standard, but not for any other purpose.  Certainly,
if he modifies it to use the patented material for some other purpose,
he won't be able to redistribute *that*... and since he won't be able
to do so, you can't distribute the GPL'd code for which you don't have
copyright.

It's possible that I'm misunderstanding you, and that what you're
really suggesting is that the patented invention be isolated in an
MIT-licensed file which is mutable under its copyright license, but
effectively immutable under its patent license.  This file is then
linked to a GPL'd program, which essentially has a use restriction: it
may use the patented invention only to implement the standard.  That
would seem to deviate from the spirit of a copyleft rather significantly.

-Brian

-- 
Brian Sniffen                                       bts@alum.mit.edu
		    http://www.evenmere.org/~bts/
	      Available for security-related employment.



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