Closed-source non-free ParallelR ?

All that being said, the entity that must enforce these conditions is
not the FSF, but the copyright owner, in this case the R Foundation
and the copyright holders of any other packages redistributed by the
bundler. So it would be useful to know what the R Foundation's
position is.  Regardless of what the license says, it is up to the R
Foundation to decide what *its* interpretation of the license is and
under what circumstances it would ask a distributor of its code to
cease and desist -- and that failing, sue.

Actually, the R Foundation has done what it is obligated to do, which  
is to describe the license under which R is made available. To ask the  
R Foundation for anything further is to ask them to render a legal  
opinion, which is not in their expertise to offer.

It is up to the prospective third party developer of an application  
that is to use R to consult with lawyers to determine what *THEIR*  
obligations are if they should elect to proceed. Since much of this  
has not yet been tested in case law, the burden is on the the third  
party developer, not on the R Foundation, since the R Foundation  
cannot reasonably conceive of every possible scenario under which R or  
subsets of code from R may be used.

The key thing to keep in mind is that the GPL really applies to the  
**distribution** of software and not the **use** of software.

Thus, if one is going to use R or code from R "internally", the  
obligations are more limited than if one builds an application that  
links to R or uses code from R and then will *distribute* that  
application to other parties, whether that distribution be free of  
charge or for a price.

There are two key scenarios here:

1. I am building an application that simply "calls" R via a script or  
batch type of interface. Think building a GUI on top of R. I  
distribute my application and may or may not distribute R with it. I  
can license my application in any fashion that I wish, closed source  
or otherwise. If I don't distribute R with my application and simply  
point users to where they can download R, then I have no obligation  
with respect to R. If I distribute R with my application, then I also  
have an obligation to make R's source code available to my users in  
some fashion. Neither situation obligates me to make the source code  
for my application available or to license my application under the GPL.

2. I build an application that includes source code from R and/or  
"links" to R libraries at a compiler level. In this case the  
"derivative works" and/or the so-called "viral" part of the GPL kicks  
in. Here, I am obligated to license my application under a compatible  
license AND make the source code to my application available as a  
consequence.

At this level, it is really pretty simple and a lot of these things  
are covered in the GPL FAQs, including the reporting of violations.

   For GPL 3:
   http://www.gnu.org/licenses/gpl-faq.html

   For GPL 2:
   http://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.html

HTH,

Marc Schwartz