Re: [pdf-devel] 3D in pdf - any plans?

[jemarch]

Hi Leonard.

   Is that comment below concerning patents & GPL really true?   

   I certainly understand issues around existing FOSS SOURCE code and the
   GPL, but I've never heard ANYONE ever say that a GPL-licensed product
   can't implement something that is patented.  Certainly, one would want
   to ensure that the licensing for said patent is granted (free, RAND,
   etc.) - but just having a patent doesn't violate the GPL, does it?!?!

You can implement patented technologies and distribute the code under
the GPLv3 as long as the owner of the patent has granted a world-wide
royalty-free license to use the patented technology. Same situation as
with the GPLv2.

The GPLv3 disposition about patents only applies if the owner of the
patent is also a _contributor_ of the software. 

From the GPLv3:

   A “contributor” is a copyright holder who authorizes use under this
   License of the Program or a work on which the Program is based. The
   work thus licensed is called the contributor's “contributor
   version”.

   A contributor's “essential patent claims” are all patent claims
   owned or controlled by the contributor, whether already acquired or
   hereafter acquired, that would be infringed by some manner,
   permitted by this License, of making, using, or selling its
   contributor version, but do not include claims that would be
   infringed only as a consequence of further modification of the
   contributor version. 

   For purposes of this definition, “control” includes the right to
   grant patent sublicenses in a manner consistent with the
   requirements of this License.

   Each contributor grants you a non-exclusive, worldwide,
   royalty-free patent license under the contributor's essential
   patent claims, to make, use, sell, offer for sale, import and
   otherwise run, modify and propagate the contents of its contributor
   version.

So, for example, If I get a GPLv3 licensed software and add a new
functionality covered by a patent that I own, I would need to give a
non-exclusive, worldwide, royalty-free license to use my patent to the
users of the GPLv3 work.

   I am concerned about the truth/validity of this statement, because Adobe
   holds standing patents on many parts of PDF that are "core" to the
   technology (both in the file format and in the rendering model) that it
   licenses royalty-free for the purposes of supporting PDF (See
   <http://partners.adobe.com/public/developer/support/topic_legal_notices.
   html>) and I would hate to see this project's progress hindered.

   Looking forward to clarification.  Thanks in advance!

Fortunately we can use your royalty-free licenses in order to
implement PDF support under the GPLv3 :)

Hope this help.

--
Jose E. Marchesi     <address@hidden>
                     <address@hidden>

GNU Project          http://www.gnu.org
GNU Spain            http://es.gnu.org