In December 2007, the Wikimedia Foundation passed a resolution requesting that the Free Software Foundation modify the terms of the GFDL so that it could relicense to Creative Commons Attribution-ShareAlike 3.0 (US) licence. The FSF released version 1.3 of the GFDL on 03 November 2008.
This is pretty big news. Wikipedia was founded before the Creative Commons licences were available, so they naturally chose the GFDL, which is the FSF's copyleft licence for text based works. The GFDL was designed to be used with manuals, help files and text books. It is quite an unwieldy licence that requires that each distribution be accompanied by the entire text of the licence. It also has express provision for invariant texts, areas of the work that are marked out to be immutable and thus non-free.
As a strong copyleft licence, the GFDL 1.2 required that all distributions of modified material be licensed under the GFDL. This means that works licensed under the GFDL are incompatible with all other licences. This means that text on wikipedia cannot be incorporated into works licensed under, for example, the GPL or a CC BY-SA licence. This means that it can become very difficult to make really interesting mashups. The paradigmatic example I use is that of an interactive educational game that combines a free software engine (GPL) with a set of wikipedia articles (GFDL), a tour guide from wikitravel (CC BY-SA v1), images from Flickr (CC BY-SA v2) and a soundtrack from Jamendo (CC BY-NC-SA v3). It may be technically possible to separate out all of the individual components (or seek extra permissions from all the copyright owners), but if it's not, the result will be a free, innovative educational interactive tourist guide which can never legally be distributed.
This is an unfortunate example of unintended incompatibility. We know that copyleft material cannot be mixed with material which is not available for free licensing, and this is desirable, because it builds the commons by encouraging people to release their modified works under a free licence. It also restricts exploitative behaviour by preventing people from taking material from the commons and locking it up for their own gain without contributing back. This is intended incompatibility. The problem comes when we make several different licences with roughly the same goals, but we draft them in such a way that they remain incompatible with each other. Because licensors rarely choose a licence based upon the particular legal wording of the licence, but instead rely upon the high level abstractions or the stature of the organisation behind the licence, then where those high level abstractions are very similar, it makes little sense for the licences to be incompatible.
The danger is that the commons we are building may still be an anticommons. In a 1998 article, Michael Heller defined an anti-commons as a situation where there were too many rights to exclude to achieve socially desirable outcomes. A tragedy of the anticommons in open content licensing occurs when authors release their content in the hope that it will be reused but under licences which unintentionally limit its utility.
This occurs when some people release material under, for example, the GPL, and others release material under CC BY-SA. At a high enough level, these licences look the same – licence modified versions under a copyleft licence, attribute the previous authors, a few disclaimers of liability, and we're done. Unfortunately, due to some differences in wording and implementation, the licences are somewhat legally different, and for these reasons, they each insist that modified versions be released only under the original licence. So, someone who wants to make use of material licensed under two incompatible licences has to ask permission from each copyright owner – exactly the same position we would be in without the licences. This is the tragedy of the anticommons.
In the past few years we've seen a drop in the use of vanity licences, and authors in the free software community have generally consolidated around a relatively small number of licences. We've also seen some significant changes by the main interested organisations. The OSI has established a License Proliferation Committee, with goals to educate licensors about their choice of licence; the FSF has introduced mechanisms in GPLv3 to enable code under previously incompatible licences (particularly Apache v2) to be integrated with code under the GPLv3; and Creative Commons has introduced a concept of Compatible Licences into version 3 of its ShareAlike licences which allow relicensing under 'approved' licences (of which there are still none). Other groups like Google Code have imposed restrictions on the number of licences that they support (but later reversed their decision and expanded the list of licences available).
So this move by the FSF has been long awaited and is very welcome. Lets take a look at what's changed.
Version 1.3 introduces one of the changes to the GFDL that were introduced in GPLv3 – a compliance mechanism. Previously, the licence automatically terminated on breach. Now, if someone breaches the licence but fixes the breach, the licence is reinstated. The same timelines apply as they do to the GPL:
You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.
Clause 10 introduces another change introduced in the GPLv3, that a licensor may appoint a proxy to determine whether the licensed work can be relicensed. This is important because generally, only the copyright owner may change the licence. By appointing a single proxy (or a small number of proxies), members of a community can ensure that their code or text is able to be relicensed under future versions but does not automatically version up – a protection against potential tyrranical practices by the FSF.
If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Document.
Clause 11 is the important one for Wikipedia. This is the clause which allows one-way relicensing under CC BY-SA 3.0. It is limited in a number of ways:
Only applies to a “Massive Multiauthor Collaboration Site”, which must be a web “server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works” – a wiki is given as an example of such a site. I'm guessing that the word 'anybody' here is not meant to be absolute, but it seems a bit ambiguous. Some people, after all, are banned or cannot access wikipedia.
Only applies to CC BY-SA 3.0. Importantly, 3.0 SA has it's own version up clause and allows relicensing under the various jurisdiction licences.
Does not apply to any works which use invariant sections or cover texts (apparently, unless those invariant sections or cover texts were imposed by the wiki ('MMC Site') originally – not much of a distinction, wikipedia doesn't use invariant sections or cover texts).
Only applies to works which are incorporated into the wiki prior to 01 November 2008. This restriction means that one cannot take a software manual licensed under the GFDL and post it on a public wiki and then relicense it under CC BY-SA. It is said to prevent 'gaming' of the system. This time limit only applies to works first published elsewhere and then incorporated on the wiki. There is no restriction for works which are first published on the wiki that wishes to relicence. This means that for wikipedia, there should now be an effective freeze on new additions of GFDL material which has been published elsewhere. New edits under the GFDL will still be able to be relicensed, but edits sourced from elsewhere will not.
Only the 'operator' may relicense. No dice if we want to take a DB dump of wikipedia and release ourselves. Interestingly, a wiki that forked before 01 November 2008 should be able to relicense regardless of whether wikipedia does; new forks may not relicense.
the 'operator' must relicense before 01 August 2009. The option will not be available after that.
“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.
“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.
“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.
An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.
Great news from the FSF. Wikipedia should relicense as soon as possible to avoid potential conflicts where people import GFDL-licensed content after 01 November 2008.