How To Break The GPL

Rod Dixon, J.D., LL.M. rod at
Sun Mar 5 01:48:30 UTC 2000

The confusion regarding a "derivative work" could be cleared up by reference
to the Copyright Act. Some people have been confusing distinct concepts of
copyright law, which sets out five exclusive rights of the copyright owner;
notably, the exclusive rights to control the creation of derivative works
and to control the distribution of those works are two of  them. Even if we
agree that Alice did not violate Trent's exclusive right to control the
creation of derivative works, it is an entirely  different question whether
Alice violated the distribution terms of the GPL. I have assumed the GPL was
a GNU-type GPL that contained a copyleft provision. If this is so, and if
Alice's source code looks substantially like Trent's code, Trent will
likely prevail on the merits (IF, and this is another big IF, the source
code reveals to the court that it contained expression subject to copyright
protection. This determination is made after the application of the
idea/expression dichotomy and/or the abstraction-filtration test. In other
words, the legal analysis here gets quite involved and perhaps beyond the
interests of this discussion thread).

Full Disclosure: just in case Alice is real, I should make it clear that I
am not offering legal advice, only commentary and contribution to a very
interesting discussion. Open source interests me because I am a law school
professor who teaches and does research in Cyberlaw.

Rod Dixon, J.D., LL.M.
rod at

> -----Original Message-----
> From: W. Yip [mailto:weng at]
> Sent: Saturday, March 04, 2000 1:57 PM
> To: license-discuss at
> Subject: Re: How To Break The GPL
> On Fri, 03 Mar 2000 15:56:06 -0500, John Cowan <jcowan at>
> wrote:
> >"Forrest J. Cavalier III" wrote:
> >> Says who?  If she distributed a derivative work of GPL'ed software,
> >> then it must be GPL'ed.  The question is whether or not Alice has
> >> a derivative work.
> >In my first scenario, Alice made a derivative work but didn't distribute
> >it.  She then distributed her own original work to Bob, who made another
> >distributed work (identical to the first one) but didn't distribute it.
> >Again I propose the analogy:  I mark up my copy of a certain copyrighted
> >book, correcting certain errors in it.  I now mail you *only* the errata
> >and corrigenda, which you incorporate into your copy.  Now we
> each have a
> >copy of the same derivative work, but nobody *distributed* the
> derivative work.
> It seems to me this is the crux of the problem.
> Alice may have
> (i) infringed the copyright vested in Trent.
> (ii) breached the terms of the GPL
> It seems to me that potential claims in the two cases vary.
> In regards (i), Alice is unlikely to have infringed copyright because she
> is a licensee under the terms of the GPL which expressly allow
> her to copy,
> adapt, etc.
> The problem tends to be in (ii). Alice MUST have agreed to the
> terms of the
> GPL, or otherwise she would be infringing copyright as in (i). It follows
> that in agreeing to the GPL, she has to fulfill its viral nature by
> ensuring that any redistribution she makes, whether modified or otherwise,
> is made under the GPL too. This is because the GPL covers
> distribution, and
> that only, since it is a license that governs sublicenses.
> John Cowan has pointed out the possibility that Alice can
> effectively cause
> Bob to acquire Alice's derivation WITHOUT distribution. The issue here is
> that since there is no distribution made, the GPL has not been breached.
> Trent therefore can neither claim under (i) or (ii).
> Subsequent contributions to this thread have suggested that the definition
> of 'derivative work' may/may not encompass 'distribution'.
> I submit that 'derivative work' as (i) a category of significantly changed
> code is different from 'derivative work' as (ii) a manner of distribution.
> It seems to me that (ii) is as yet unseen of, although John Cowans has
> shown us how that may be possible. In regards linking, I think merely
> linking or calling by function cannot be seen as distribution.
> However, if we suppose Alice sends a file containing errata ONLY
> (no source
> from the original) to Bob, can this be seen as 'distribution' of a
> 'derivative work'?
> I think the outcome of this program falls to how the courts interpret
> 'derivative work'. I think it really depends on how dissective the courts
> want to analyse the program.
> regards

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