On Thu, 21 Nov 2002, Christopher K. St. John wrote:
> On Thu, 21 Nov 2002, ddutt@xxxxxxxxx wrote:
> > What drawbacks do you see in changing the plugin license ? I haven't
> > been able to make out what your worries are. Can you repeat them to
> > me one more time ?
> The main problem is that the whole "The GPL stole my patent!"
> argument is complete nonsense.
I think you are correct to say that GPL doesn't invalidate a patent or
make it unenforceable. But that is not the point.
The GPL requires that "any patent must be licensed for everyone's free use
or not licensed at all." Well, what does "use" mean here? Since patents
protect *ideas* rather than *expressions*, does this mean that in
accepting a GPLed program I automatically receive a license to use the
patented ideas embodied by it in *any* way, or only in the context of the
original work and any modification thereof which I might make? *That*
seems to be what makes the lawyers nervous. Why would anyone pay for
licenses when he could get them for free by accepting some bits of
software, extracting the ideas, and throwing the software away?
Unless clear limits are set on "use", there's no point in patenting ideas
embodied in GPLed code, because (since it may be that everybody thereby
receives an unlimited license to practice those ideas) there is no
practical way to maintain a monopoly in selling works based on your ideas
or to demand license fees of others who want to sell them -- which is the
whole reason for seeking patents. As I reread the GPL, I become more
firmly convinced that GPLing a work based on patented ideas should not be
done unless one has decided to stop using the relevant patent as a
bargaining tool in other contexts.
On the other hand, GPL also states that it applies to "any derivative work
*under copyright law*." [Emphasis added.] I don't know precisely how
copyright law defines "derivative work", so there may be limits on just
how far you can remove the ideas from the code, beyond which GPL would not
apply. Since the bit about patents "licensed for free use" occurs in the
Preamble and not in the Terms and Conditions, one could argue that any
such limits supersede the possible blanket claim stated earlier. (Does
your head hurt yet? Mine does.)
Even if the "free use" bit were found to be limited to the original
expression and reasonable modifications of it, I think that a GPLed
project should not accept GPLed code containing patented ideas unless an
additional license is offered, granting permission to use the patented
ideas specifically within such expressions. Copyright and patent are
related, but it is the *interaction* of the two which gives us trouble
here and we need to deal with them separately in order to precisely
define that relationship.
So it does seem to me that either changing the license on the affected
code, or establishing an "arms'-length" relationship between Ethereal and
any extensions containing patented ideas, would be a really good idea if
one is unwilling to turn down the offered extensions.
(Disclosure time: I just recalled that I own (very little) Cisco stock.
I believe that that does not influence my thinking on this matter, but
you may choose to believe otherwise.)
--
Mark H. Wood, Lead System Programmer mwood@xxxxxxxxx
I continue to not be a lawyer.
