Since Friday, 15 June 2007 there has been lots of uncertainty in the Joomla! community due to an article published by the Joomla! Development Team on joomla.org.
This was caused by a discussion about whether or not Joomla! 3rd-Party extensions can be released under a license which is incompatible with the so called GNU/GPL.
It is the opinion of the Joomla! developers, that if a 3rd-Party extension (Component, Module, Mambot or Template) communicates with Joomla!'s programming interface, the 3rd-Party extension forms a work based on Joomla! (derived work), which then – just as Joomla! itself – has to be licensed under GPL or another GPL-compatible license.
Most of the commercial extensions available for Joomla! – among them XHTMLSuite – are released under so called proprietary licenses (cp. Wikipedia: proprietary software license). These are intended to protect the intelletual property and prevent the work of the authors from being redistributed unallowed. In general proprietary software licenses by definition are not compliant with the GPL.
The XHTMLSuite License and Joomla!
Up until recently there was a FAQ on the Joomla! help pages with answers to the 15 most asked questions regarding Joomla!'s license. Section 10 stated the following1:
10. I have written a Component, Module, Template for Joomla. Do I have to release it under the GPL?
No. The GPL allows you to write your own extensions for Joomla and to release those extensions under whatever license you chose.
On the German Joomla! homepage however the translation of the original version (up to the time this article was published) was still available under the URL http://www.joomla.de/content/view/3/7/1/1/:
10. Ich habe eine Komponente, Modul, Template, Joomlat für Joomla geschrieben. Muss ich diese auch unter der GPL veröffentlichen?
Nein! Die GPL erlaubt Ihnen Erweiterungen für Joomla zu schreiben und diese in jeder erdenklichen Lizenz zu veröffentlichen.
Meanwhile the questions and answers on help.joomla.org were archived and aren't accessible for the public anymore and the first mentioned article on joomla.org from 2007-07-15 now states exactly the opposite:
Can I release an extension under a non-GPL license?
It is our opinion that most extensions are derivative works of Joomla! and must be licensed under the GNU GPL. It is possible that an extension could work within Joomla! and not be considered a derivative work according to copyright law but this would have to be evaluated on a case-by-case basis. If you believe your extension is not a derivative work we strongly recommend that you seek professional legal advice.
What does that mean for you as an XHTMLSuite end-user?
Is the usage of XHTMLSuite illegal?
No, not in the least! The Joomla! Developer Team is at one, that the GPL grants every right to the end-user, to run the Software (Joomla!) in the way she/he wants to, this also includes extending Joomla! with proprietary Software. In the event of an enforcement of the License Guidlines through Joomla! only XHTMLSuite.com as publisher would be affected, never you as an end-user.
Will the development of/support for XHTMLSuite now cease?
No, we, as hitherto, will continue to develop and distribute XHTMLSuite further and will actively support to the best of our knowledge when you have questions or problems. We are in contact with the Joomla! Core Team and are closely following the process in order to resolve this with a result agreeable for both parties.
Is XHTMLSuite now licensed under theGPL?
No, XHTMLSuite is still released under the XHTMLSuite License, which is however incompatible with the GPL. This incompatibility in our opinion would only come to effect if we would distribute Joomla! and XHTMLSuite together, for example as a Software Bundle.
Does the license of XHTMLSuite need to be changed?
On the question put forward by XHTMLSuite Lead Developer Bernhard Pfeifer, if it was the case, that XHTMLSuite is to be considered a separate work and thus, as hitherto, can be released under a proprietary license, Joomla!'s Project Manager Johan Janssens answered, that this was correct. According to Janssens, parts of XHTMLSuite, that directly link to Joomla! (for example the XHTMLSuite Mambot and the Component) have to be released under the GPL. Distributing a package containing GPL and non-GPL Software should be absolutely feasible though, like Joomla! Lead Developer Louis Landry states in his Blog.
We have commissioned an expert in the field of Open Source Law to examine to what extent a license change of Component and/or Mambot will in fact be necessary.
Why is XHTMLSuite an exemption (separate Work)?
Why does the XHTMLSuite.com Team distribute Software incompatible with Joomla!'s license?
We were and until now are still confident of doing this lawfully and in compliance with the guidelines of the Joomla! project.
We'd like to state here that we consider the whole XHTMLSuite application package, i. e. the Component, the Mambot and the WYSIWYG editor itself, as a separate work respectively as individual separate works and not as derivative works and that they therefore do not need to be released under the GPL.
If you have any questions regarding this matter, you are welcome to write us an E-Mail.