[Rd] Copyright versus Licenses

[Thomas Lumley]

On Mon, 18 Jan 2010, Bryan McLellan wrote:

> My company recently started using a R library from RCRAN that is
> licensed under the LGPL Version 2 or greater per the DESCRIPTION file,
> but contains no copy of the LGPL notice, or any copyright notice. I've
> grown accustomed to paying attention to copyright and licensing as a
> Debian package maintainer, and sent the author of the package an email
> expressing my concern. The author believed that assigning themselves
> copyright was incompatible with licensing the library under the terms
> of the LGPL. I disagree, and further contend that without copyright
> notice, the [copyright] license loses a certain degree of
> applicability, as it becomes inconclusive as to who is licensing the
> software under the terms of the LGPL. Not knowing who I was, the
> library author asked me to start a discussion of the subject on this
> list, presumably so they could see the opinions of others that they
> trust.

Like Simon, I'm speaking only for myself here.

Not having an explicit copyright statement certainly makes it harder for people downstream who have questions, so explicit statements seem like a good thing.

> The LGPL itself [1], in the final section entitled "How to Apply These
> Terms to Your New Libraries", the license provides a template for
> adding to the top of each source code file that contains a copyright
> line, a general notice regarding the lack of warranty, and information
> on where to obtain a full copy of the license. The GPL HOWTO [2]
> expresses similar instructions for the inclusion of a copyright line
> with the license. I know that R distributes copies of common licenses
> under 'share/licenses' in the R source. Debian does as well in
> '/usr/share/common-licenses/' for the purpose of not having to include
> the full LICENSE and/or COPYING file with every package that uses a
> common open source license, allowing the use of verbage such as "The
> Debian packaging is © 2010 [author] and is licensed under the Apache
> License version 2.0. On debian and derived systems, see
> `/usr/share/common-licenses/Apache-2.0' for the complete text." The R
> manual for writing extensions suggests a similar approach to avoiding
> duplication in Section 1.1 [3].
>
> The R manual for writing extensions also mentions [4] in Section 1.1.1
> the optional use of a Copyright field in the DESCRIPTION file,
> separate from the License field. As this section implies that the
> DESCRIPTION file format is based on the debian control file format, I
> assume the goal is to keep these lines simple, generally under 80
> characters do to average terminal width. As such, I don't assume this
> field is recommended for complete copyright information for a library
> with multiple contributors. The aforementioned article does not
> specify where a developer should alternately put copyright
> information, perhaps assuming one would add it to each source code
> file as is recommended by GNU.

Yes, in the source code is good.

In addition, if you look at the source code for R, the approach there has been to have a file COPYRIGHTS that lists the original copyright holders of bits of the code.  This seems like a good idea if there are multiple sources.  It's especially useful if there are areas of doubt and uncertainty (eg code published on ftp sites before people worried about licenses), since it at least gives you rigidly defined areas of doubt and uncertainty[5]


> In closing, do the R developers believe that including a Copyright
> notice is imperative with a Copyright License?
>
> If so, what advice do they have for those writing and contributing
> open source R libraries as to where this notice should go?
>
> Should that information perhaps be added to the R manual for extensions?
>
> Bryan McLellan
>
> [1] http://www.gnu.org/licenses/lgpl-2.1.txt
> [2] http://www.gnu.org/licenses/gpl-howto.html
> [3] http://cran.r-project.org/doc/manuals/R-exts.html#Package-structure
> [4] http://cran.r-project.org/doc/manuals/R-exts.html#The-DESCRIPTION-file
>
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>

     -thomas

Thomas Lumley			Assoc. Professor, Biostatistics
tlumley at u.washington.edu	University of Washington, Seattle



[5] Adams D, (1978) Hitchhiker's Guide. BBC Radio.