[License-discuss] GPL and proprietary WebAPIs

[Rick Moen]

Quoting Clark C. Evans (cce at clarkevans.com):

> What was also on my mind was an informal side chat
> with an attorney on the stack overflow question [1].
> I was referred to the GNU FAQ, especially the answer
> for plug-ins [2] where the applicability of the copyleft
> "depends on how the program invokes its plug-ins" and
> aggregation [3] where it says "sockets...  are normally
> used between two separate programs".  This attorney
> said the specific details of the case were necessary
> to give any advice, but after my insistence, commented
> that the community consensus is likely correct.  

OK, thanks for clarifying.  There are several claims in FSF's GPL FAQ
that are rather infamously misleading and doubtful, that being the most
notorious one.  When one reads caselaw clarifying the concept of
derivative work, it becomes obvious that the claim stated there is
simply incorrect.

You will, I suspect, also come to the view that no method of software
intercommunication is a magic talisman.  One creative work is derivative
of the other, or is not, as a result of a judge's application of
standard conceptual criteria used in copyright cases.

You will find scant 100% relevant caselaw, however.  A few examples of
what you will find:

o  2010 suit against Westinghouse Digital Electronics (I believe,
   settled on plaintiff's terms) 
o  2010? suits against Best Buy, Samsung Electronics America, and JVC
   Americas (I believe, settled on plaintiff's terms)
o  2009 suit against Edu4, Paris Court of Appeals
   (adjudicated for plaintiff)
o  2008 suit against AVM Computersysteme Vertriebs GmbH and Cybits AG
   (adjudicated for plaintiff)
o  2008 suit 'Welte vs. Skype Technologies SA' in a German court
   (adjudicated for plaintiff)
o  2007 suits against Xterasys and High-Gain Antennas (probably settled, 
   not adjudicated)
o  2007 suits against Monsoon Multimedia (settled, not adjudicated)
o  2006 suit against D-Link Germany GmbH
o  2005 suit against Fortinet UK Ltd. in Munich district court
   (preliminary injunction upheld)
o  2004 suit against Sitecom Deutschland GmbH in Munich district court 
   (preliminary injunction upheld)
o  2001 suit against Dlink Deutschland GmbH in a Frankfurt court
   (adjudicated for plaintiff)

Harald Welte at http://gpl-violations.org/ has a lot more (a bit over
100 cases, very few adjudicated).  The point is, though, that pretty
much all of the cases have involved embedded hardware manufacturers
being dumb, mulish, and not even the least bit clever in redistributing
either the Linux kernel, iptables/netfilter, or Busybox, and refusing to
offer matching source code.

None of these have directly involved the sort of technological shim
workaround you are curious about, so you are logically reduced to
predicting how a judge would rule based on copyright cases and your
understanding of derivative works generally.  Clue:  Judges are rather
likely to ignore handwaves about magic-talisman technology, and to apply
conceptual tests from copyright caselaw to determine whether the
allegedly infringing work is derivative or not.

And, to the extent there is doubt, and that the probabilities will
depend on the specific facts of cases, sorry, there's simply doubt.  


> Unfortunately, this doesn't give me enough guidance on
> the applicability of copyleft; specifically with my
> 3-work scenario where someone uses a shim/adapter to
> include proprietary functionality via a WebAPI.  I keep
> asking this in this public forum since it matters quite
> a bit to the effectiveness of the GPL.

What you really should be doing -- to understand the underlying law --
is studying what leads judges to believe that one work is derivative of
another.   (That of course does not tell you what is 'acceptable to the
community[1]', an entirely different question.)  You'll also want to study
contract law, which is often and perhaps always relevant alongside
copyright law.

> ...does the GPLv3 actually prevent...

GPLv3 doesn't prevent a blessed thing.

Copyright law and contract law make particular actions concerning
software and other creative works tortious, making it possible for the
offended party to get remedies in law and (maybe) in equity.


[1] I don't see what 'the community' has to do with the matter at hand.
If there's an alleged tort, someone with standing either sues or not.
If he/she sues, the case is well argued or not.  Plaintiff prevails or
not -- and 'the community' isn't particularly relevant.