[time-nuts] Open source

David Kirkby david.kirkby at onetel.net
Sat Dec 8 09:17:30 UTC 2012

On 8 December 2012 08:36, Poul-Henning Kamp <phk at phk.freebsd.dk> wrote:

> And one other detail most people overlook, is that the default GPL text
> gives any users the right to use any later version of the GPL license
> instead of the one you copy&pasted.  This has only happened once but
> it had ground-shaking repercussions through out the industry.

I don't agree with that statement.

Look at GPL 2 (not the latest version).


Section 9 states:

"Each version is given a distinguishing version number. If the Program
specifies a version number of this License which applies to it and
"any later version", you have the option of following the terms and
conditions either of that version or of any later version published by
the Free Software Foundation. If the Program does not specify a
version number of this License, you may choose any version ever
published by the Free Software Foundation."

Note the term:  "*IF* the Program specifies ..."

My interpretation of the GPL if you specify version 2, and do not
specify "or any later version", then the code is released under
version 2, and can't be used under any later version.

This compatibility matrix


makes it clear if the code is released under GPL 2, without the "or
any later version" clause, it is incompatible with version 3.

> And as was said, there is a ton of other OSS-licenses out there,
> you can see a sort of a list here:
>         http://opensource.org/licenses/index.html

Unfortunately, the large number of licenses is a real pain. The Sage
mathematics project


which aims to create a viable free open source alternative to Magma,
Maple, Mathematica and Matlab, is plagued by the problem of
incompatible licenses, Sage contains the source code from around 100
different bits of software and needless to say some are incompatible.
In some cases, when consideration was given to including the source of
some program X released under the GPL 2, the projects lead (William
Stein) or someone else has contacted the original author of X, and
asked them if they will re license it under "Version 2 or any later

In other instances, packages were made optional, so people could
install them if they wanted, but it would be under a different

Personally I'm not convined that Sage fully complies with the licenses
and I'm not the only Sage developer to think that. But the projects
lead is happy.

The amount of time spent on the Sage developers mailing list
discussing license issues is not insignificant. This is a direct
result of various components having different licenses.


More information about the time-nuts mailing list