Licence change

Dear list,

For the maintainer of a given package, is it possible to change the
licence of a it from GPL >= 2 to GPL >= 3 ?

Are you the author and copyright holder of everything in the package?  
If so, then I think the answer is yes.

If not, then what license did the author give you for the parts you 
didn't write?  You'll need to consult that, to find out if you can still 
distribute the code with a more restrictive license.  For example, if 
you're using some code that was licensed under GPL 2 (not GPL >= 2), 
then you need permission from the author of it to distribute it under a 
different license.

If you are distributing the package on CRAN, you'll have to ask them 
whether they'll still choose to distribute your package after the change.

Duncan Murdoch