Subject: Re: termless copyright and patents
From: Thomas Lord <lord@emf.net>
Date: Fri, 06 Oct 2006 09:12:40 -0700


Simo, I think the nib of the gist of our disagreement is summarized by
your comment:


  Simo> "Patent claim" is a very specific legal term, no doubts on its
  Simo> meaning.


If you splice together the definitions and section 11, you
find that the covenant covers:

   all patent claims

   that the [conveying] party can give permission to practice

   [....] that would be infringed by making, using, or selling [the
   conveyed work]

   [and] which arise from [the] exercise of rights under this
   License [as applied to the conveyed work]


Let's start with "patent claims" that a "party can give permission to
practice".    If my antilock break patent claims "#2 ... in a vehicle
...", I *can* give permission to practice the patent in any vehicle at
all.  On the other hand, my broad claim implies many narrower claims.
I may also give permission just for "in a vehicle with capacity for 6
adults or less".   That narrower language, though not found explicitly
in my patent, is a claim to which I may give or withhold permission.

Well, per GPLv3d2 I'm supposed to give up "*all* claims" but what does
"*all*" mean here?   Well, it is kindly explained, I must give up
"*all*" claims which would be infringed by making, using, or selling
the work I conveyed -- no more and no less.

If my patent reads "#2 ... in a sort program ...." I *can* give
permission to use the algorithm in any sort program at all -- but I
can also subdivide my property and give permission, on the one hand,
for line-based sort programs and, on the other hand, for record-based
sort programs.   Just like I can give permission to use my antilock
breaks in passenger cars separately from giving permission to use them
in busses.

But what about that "*all*"?  Well, it is "*all* ... that can arise
..."  I conveyed a line-sorting program.   No matter how you make,
use, or sell the program I conveyed it won't do record sorting.  So my
sub-claim for record sorting is not part of "*all*".   In fact, to
insist that I convenanted record sorting would mean that I gave up
something *more* than *all* of the claims I can give permission for.

Now, there is ambiguity here.  If you ask "what is the set of *all*
claims being covenanted" -- in general there will be more than one way
to construct it.  Well, that's a simple matter: the right construction
is the one that I, the conveyer, the patentee, deem to be most
favorable to me, so long as it is otherwise consistent with the
GPLv3d2.   After all, it's my property we're talking about here.

-t