Package Licences

Licences are considered to apply to 'distribution' (I'm not entirely 
sure if that is what you mean by 'released'), but some also apply to 
usage.

The primary requirements for distribution, especially over CRAN, are 
that the licence be clear and usable.  Examples of problems

- licences that prohibit distribution without further permission

- claims that some parts of a package are under one licence and other 
parts under another, without making clear what licence applies to the 
whole package.

- copying parts of the work of others (most often the R sources) 
without acknowledgement and/or with an incompatible licence.

- licences which require the sources to be made available (e.g. GPL) 
with some components without sources and no other evidence of 
availability.

- incompatibility.  If your package has licence A and 'Depends:' or 
'Imports:' other packages with licence B, then you create problems for 
users if A and B are incompatible.  A recent example is a licence that 
prohibited certain classes of users and another that prohibited any 
restrictions on use.

See 'Writing R Extensions' for the requirements of the LICENSE field 
in the DESCRIPTION file.  Life is much simpler for the users 
(including the CRAN maintainers) if one of the standard forms is used, 
since automated checking is possible.

See also https://stat.ethz.ch/pipermail/r-devel/2009-May/053248.html 
for a related policy statement from the R Foundation.

Ultimately the discretion is of those doing the distribution, e.g. the 
CRAN maintainers (and I am not writing on their behalf).

Are there any particular licences under which R packages must be 
released or is it the discretion of the author? The same question if 
the package is to be destined for CRAN?

Kind regards,
Nathan

-- 
--------------------------------------------------------
Dr. Nathan S. Watson-Haigh
OCE Post Doctoral Fellow
CSIRO Livestock Industries
Queensland Bioscience Precinct
St Lucia, QLD 4067
Australia

Tel: +61 (0)7 3214 2922
Fax: +61 (0)7 3214 2900
Web: http://www.csiro.au/people/Nathan.Watson-Haigh.html

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