Matt Mullenweg, the founder and lead developer of the WordPress blogging platform, emailed the Software Freedom Center recently asking about the legality of WordPress themes being licensed under copyright not compatible with the GPL, and they’ve now responded, which Matt has published on the WordPress Development Blog.
The conclusion? The PHP files in WordPress themes must inherit the GPL, but CSS and Images do not. From the email:
The PHP elements, taken together, are clearly derivative of WordPress code.
But because neither side can claim they were 100% correct, the declaration is bittersweet to those on both sides of the issue.
Those claiming that themes must be completely covered by the GPL can no longer claim that:
… the images and CSS are not [subject to the requirements of the GPL]. Third-party developers of such themes may apply restrictive copyrights to these elements if they wish.
But those claiming that they can license their themes — in their entirety — under a restrictive license seem to have been in the wrong as well. Or were they?
In the last paragraph of the email, it seems there is, at the very least, a potential loophole.
Finally, we note that it might be possible to design a valid WordPress theme that avoids the factors that subject it to WordPress’s copyright, but such a theme would have to forgo almost all the WordPress functionality that makes the software useful.
If it’s possible, though not ideal, for a WordPress theme to run independent of WordPress itself, then one must assume (at least from the wording of that paragraph) that the PHP code isn’t necessarily required to be subject to the requirements of the GPL.
Obviously, this is the first time anyone has been able to speak about the issue with authority, so this is helpful. But I’m afraid this story isn’t over yet.
I, obviously, support licensing themes (free or paid) under the GPL. But despite this latest news, I’m still very reluctant to say that the legality of the issue has been completely cleared up. There are still too many questions, and not nearly enough answers. One thing is for sure, theme authors have been adopting the GPL all over the place lately. And WordPress just launched their commercial GPL theme directory today. Perhaps the legality of all this GPL talk doesn’t even matter any more.
What do you think?