Re: gEDA-user: More footprint stuff

[DJ Delorie <dj@xxxxxxxxxxx>]

> I do, however, have one question: Exactly how does the gpl play into
> the use of elements/footprints in commerical designs? Would someone
> on this list who is who has been there/done that, chime in?!

IANAL, but in general, PCB's GPL license doesn't apply to boards
designed with PCB, as the GPL covers "derived works" and the resulting
board file has no content in it that was originally part of the PCB
program.  So I don't think the GPL on PCB itself is going to stop you
from creating proprietary boards.

Of course, this assumes you don't use footprints from PCB, as those
footprints *do* become part of your board and thus may cause it to be
a "derived work" of newlib (not pcb the program).  In theory, newlib's
footprints are GPL'd (only because the GPL is the only license
mentioned in PCB's source tree) and cause your board to be GPL'd if
you use them.  If you create your own footprints, you are of course
allowed to license them however you want.

Ideally, the license on PCB footprints would include an explicit
exception that allows the footprints to be used to create boards with
PCB, without causing those boards to become GPL'd.  GCC's runtime has
a similar exception:

  "As a special exception, if you link this library with files
   compiled with a GNU compiler to produce an executable, this does
   not cause the resulting executable to be covered by the GNU General
   Public License.  This exception does not however invalidate any
   other reasons why the executable file might be covered by the GNU
   General Public License."

Similar wording would allow footprints to be freely used by PCB for
proprietary boards, but fully protected by the GPL if used outside of
PCB.