Should we choose to release using GPL3

Please discuss on RelicenseCoreCodebaseTalk.

The proposal - to use GPL3

TWiki code has the following license:

TWiki is open source software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. We would appreciate it if redistributions of TWiki and its clones retain this file in its entire form, thus acknowledging the origin of TWiki and the thousands of hours the contributors put into creating this software.

we, can thus choose to start our project off by changing this to GPL version 3.

How are the various GNU licenses compatible with each other? shows that we can 'copy code under' 'GPL2 or later', and then release our project under 'GPL3 or later' (row2, column3).

The only thing that will prevent this, is if we must release Foswiki containing 'code' that is licensed GPL2 only.

It is important that irrespective of whether or not we do this, we go over every file and package in the release and ensure we know what the license is specified as.

Why its worth considering choosing GPL3

This list is compiled from FSF's why GPL3 FAQ.

preventing User lock-in on Virtual machines

One major danger that GPLv3 will block is tivoization. Tivoization means computers (called “appliances”) contain GPL-covered software that you can't change, because the appliance shuts down if it detects modified software. The usual motive for tivoization is that the software has features the manufacturer thinks lots of people won't like. The manufacturers of these computers take advantage of the freedom that free software provides, but they don't let you do likewise.

In short, GPL3 means that we can ensure that any end user receiving a system containing our software will be able to see the source code, and will be able to modify it and continue to pass those changes on.

reduced possibilities for patent hell

GPLv3 is designed to ... extending that limited patent protection to the whole community. ... Releasing a program under GPL version 3 protects it from (any companies') future attempts to make redistributors collect ... royalties from the program's users.

GPLv3 also provides for explicit patent protection of the users from the program's contributors and redistributors.

By choosing to use GPL3, we further explicitly indemnify ourselves and redistributors from Patent issues (than GPL2 does).

and others

Further advantages of GPLv3 include better internationalization, gentler termination, support for BitTorrent, and compatibility with the Apache license. All in all, plenty of reason to upgrade.

There's also a BitTorrent distribution clause, which is only relevant for compiled modules redistribution such as nativesearch.

'GPL2 or any later version' makes this possible.

From time to time, at intervals of years, we change the GPL—sometimes to clarify it, sometimes to permit certain kinds of use not previously permitted, and sometimes to tighten up a requirement. (The last two changes were in 2007 and 1991.) Using this “indirect pointer” in each program makes it possible for us to change the distribution terms on the entire collection of GNU software, when we update the GPL.

If each program lacked the indirect pointer, we would be forced to discuss the change at length with numerous copyright holders, which would be a virtual impossibility. In practice, the chance of having uniform distribution terms for GNU software would be nil.

...

Consequences to contributors

Any external software incorporated within Foswiki must have license terms compatible with GPLv3. Note this does not include software licensed under only GPLv2.

Based on the GPL FAQ, it would appear that Foswiki plugins would be considered to part of the Foswiki program, and so subject to the same license terms as Foswiki. Thus all plugin and extensions would also use GPLv3-compatible license terms, and limit bundled software components to those compatible with GPLv3. Currently, plugins need to be compatible with GPLv2.

Trademark considerations

GPL does not require that a project's trademarks be released under GPL as well. Requiring this would prevent a project from being able to control its official releases. (See http://colas.nahaboo.net/twikiirc/bin/irclogger_log/twiki_fork?date=2008-11-09,Sun&sel=916#l912 for a question raised about trademarks and the GPL.)

License Audit.

Before we release anything, we must ensure that all licenses are correct and compatible.

---

Discussion

RelicenseCoreCodebaseTalk