[Rd] Copyright issues question

[Prof Brian Ripley]

On Wed, 16 Jun 2004, Philippe Grosjean wrote:

> > Thomas Lumley answered:
> >
> > >It might also be worth pointing out that the R Core Team's agreement is
> > >neither necessary nor sufficient.  The GPL permits whatever it permits,
> > >and R as it stands is covered by the GPL, rather than by what the
> > >developers would like on a case-by-case basis.
> >
> > >	-thomas
> >
> > OK, that is probably true. However, in GPL 2, you have:
> >
> > 10. If you wish to incorporate parts of the Program into other free
> > programs whose distribution conditions are different, write to the author
> > to ask for permission.
> >
> 
> >There are two points here.  The first is that, as Duncan has pointed out,
> >the R distribution contains GPL code written by people other than us.  It
> >might well be possible to extract a working subset that we could release
> >under another license, but it would take quite a bit of effort.
> 
> >The second point is that one of your concerns is about areas where the GPL
> >is not clear.  If it isn't clear to you then asking us won't help. We are
> >not experts in what the GPL means, nor do we have the authority to change
> >what it means.  It would still be polite to ask about uses of R that the
> >developers might personally object to, but there is no legal benefit in
> >doing so.
> 
> >On the other hand, as the early history of KDE shows, it is possible for
> >free software to be produced and become popular even when there are honest
> >differences of opinion about the legalities.
> 
> >	-thomas
> 
> Thomas,
> 
> Sorry if I did not expressed correctly what I meant, but my query was to
> make sure all programs presented in the R GUI Projects web site have valid
> licensing terms. As it seems to be some difficults points with plugins and
> GUI, I ask the question to the R core Team and other developers on this
> list, just in case someone got a clearer answer than the one I can get
> myself.
> 
> Let's me reformulate the questions in a simpler way:
> 
> 1) Is it OK to develop GPL plugins for commercial software, and to bring
> functionnalities of these GPL software into those commercial programs,
> namely, plugins based on R for Excel, like RExcel and RxlCommander?

Definitely OK to develop them.  GPL is about distribution.  I don't see 
any issue here as you are not distributing Excel.  It's OK that gcc uses 
proprietary runtime libraries on Solaris (and elsewhere) for example.

For many years Doug Bates and others have distributed GPLed S addons.  
That seems to cause no difficulty until commercial distributors want to 
include them, when they need a different licence (which they do have in 
the prominent cases).

> 2) Is it OK to make a GUI on top of R, and to distribute it under a
> different license than GPL, like Statistical Lab, Brodgar, or JGR?

That's the murky one, and depends on the precise meaning of `on top of'.
If like Rcmdr this were a pure R package then to deny this would be to say 
that any distributed R code must be GPL-ed and that is not the common 
understanding (nor than of the CRAN hosts).

> 3) In case there is no clear answer to these questions (which seems to be
> the case), is it OK to support such plugins or GUIs that possibly violate
> the GPL license, for instance, by distributing them, or by placing links to
> them in the R GUI Projects web site?

I think it is agreed that making an HTML link is OK, although it might be 
to point out that you do not recommend using Whizzy-R-GUI as it cannot be 
distributed with R.

Your questions are not precise enough to be answered.  And if they were, 
as Thomas has said repeatedly the onus is on the distributors of such code 
to meet their obligations, not the R developers to enforce them (or even 
advise what they are).

As practical advice, in your position I would be seeking an undertaking 
from the developers of the various components that their usage is 
consistent with the R licence(s).  That might cause some of them to ponder 
the issue.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595