Of course it can render I’m not an idiot but you are missing the point. In the theme case the theme will be useless as in not providing the intended function (in almost all cases) when you remove CSS and images. The combination of html,php, images and css is what constitutes the theme or the work, this work then needs to be combined with Wordpress to function. If you remove the images and the css it is no longer the same theme/work.

Except that:

1) HTML is output by the PHP, and is otherwise irrelevant

2) Each PHP file is a separate work. Each image is a separate work. Each CSS file is a separate work.

(Again, the truth of this statement is understood when one realizes that any individual PHP file, image, or CSS file can be replaced by another such file – especially since the replacement file can have an entirely different license than the original.)

When this point is understood, the argument that the theme is only considered to be a work “as a whole” falls apart entirely. True, a theme as a whole is a work itself; however, that doesn’t negate the individual works from which the theme as a whole is constructed.

Each individual work doesn’t necessarily require WordPress in order to function – primarily, the images and CSS.

(To take the point even further: technically speaking, one could write entirely different functions with the same names as the WP functions, thus allowing even a PHP file to function outside of WordPress.)

If the theme makes use of calls to Wordpress functions which are GPL the theme has to be GPL or some other compatible license. That is why I would interpret the images and the css also has to be GPL. As the theme is to considered as a whole and would not be the same theme if you removed the CSS and images. You could also write an exception with the GPL saying it is allowed to use these non-GPL stuff given certain conditions. (See last link)

1) The GPL inheritance only applies to those components of the theme that make calls to WP-defined functions. Since neither images or CSS files make calls to anything – in fact, they do nothing except exist – GPL inheritance doesn’t apply.

2) The theme isn’t only considered as a whole; never has been, never will be. One could take components from one theme and combine them with components of another theme. One could take components from a theme and use them elsewhere. One could take components from elsewhere and use them in a theme.

3) As for the theme-considered-as-a-whole argument: such argument applies to the rendered result – which applies not to the theme components, but rather to the theme design. WordPress does not own the copyright to a theme’s design, but rather the theme designer owns that copyright. Since WordPress doesn’t own the copyright, it can’t impose its license on the work – that is, the design.

First the software would not be compatible with the GPL as is so there is no inheritance. Second your analogy is flawed. It would rather be GPL software uses a GPL plugin that uses a non-GPL plugin.
You have to write an exception in the GPL license but the theme/plugin would still not be proprietary but GPL.

No, that analogy doesn’t work, because a plugin isn’t as analogous as a library. A library is designed to work with many (or any) programs, so long as the program calls it properly. A plugin is designed to work with a specific program.

An image (or CSS) file can work with any PHP/HTML file, provided that the PHP/HTML file calls it properly. Such file does not depend on WordPress, at all.

Even to mix the analogies, and consider a plugin that calls a library: the non-GPL library called by the GPL theme does not inherit GPL from the plugin that calls it.

Again, do you really want to try to make the argument otherwise?

First, define “useless”. A theme will still render just fine (as in, without errors) without either the CSS file(s) or image file(s). For a plethora of evidence, see “CSS Naked Day”.

Of course it can render I’m not an idiot but you are missing the point. In the theme case the theme will be useless as in not providing the intended function (in almost all cases) when you remove CSS and images. The combination of html,php, images and css is what constitutes the theme or the work, this work then needs to be combined with Wordpress to function. If you remove the images and the css it is no longer the same theme/work.
If the theme makes use of calls to Wordpress functions which are GPL the theme has to be GPL or some other compatible license. That is why I would interpret the images and the css also has to be GPL. As the theme is to considered as a whole and would not be the same theme if you removed the CSS and images. You could also write an exception with the GPL saying it is allowed to use these non-GPL stuff given certain conditions. (See last link)
If I add a module to a GPL-covered program, do I have to use the GPL as the license for my module?

I’d like to modify GPL-covered programs and link them with the portability libraries from Money Guzzler Inc. I cannot distribute the source code for these libraries, so any user who wanted to change these versions would have to obtained those libraries separately. Why doesn’t the GPL permit this?
If a program released under the GPL uses plug-ins, what are the requirements for the licenses of a plug-in?
But this might be even more applicable in some cases
What license should I use for website maintenance system templates?

To make an analogy to a compiled program: your argument is analogous to saying that, if a compiled program dynamically links to two libraries – one GPL and the other not – and if that program is dependent upon both libraries to function, then the non-GPL library must inherit the GPL from the GPL library.

First the software would not be compatible with the GPL as is so there is no inheritance. Second your analogy is flawed. It would rather be GPL software uses a GPL plugin that uses a non-GPL plugin.
You have to write an exception in the GPL license but the theme/plugin would still not be proprietary but GPL. The problem is also who should write the exception. The theme/plugin developer or Wordpress copyright holders since the theme/plugin is an extension of Wordpress and not a separate entity.
What legal issues come up if I use GPL-incompatible libraries with GPL software?

I know that a large client who is implementing WP was worried about whether it allowed others to ‘steal’ their copyright work – for example, if the code was leaked (accidentally or otherwise) could somebody, in effect, legally reproduce their site’s functionality and design. The answer is a straightforward NO. In essence, the GPL does not force you into rescinding your copyright, nor is it anything like as infectious as people think.

If the theme is useless without the CSS or images one could easily argue that those files are also affected by the GPL.

First, define “useless”. A theme will still render just fine (as in, without errors) without either the CSS file(s) or image file(s). For a plethora of evidence, see “CSS Naked Day”.

Further, those CSS and image files can be plucked out, and replaced with entirely different CSS and image files – meaning that, by definition, the theme is not dependent upon those specific, original CSS files.

Second, your argument becomes incredibly twisted, and untenable.

To wit: if a theme is dependent upon a CSS file (or an image file) that has its own (for the sake of argument, non-GPL) license, as in, that theme is “useless” without said file, then why would the file upon which the theme is dependent somehow inherit the GPL?

To make an analogy to a compiled program: your argument is analogous to saying that, if a compiled program dynamically links to two libraries – one GPL and the other not – and if that program is dependent upon both libraries to function, then the non-GPL library must inherit the GPL from the GPL library.

Do you really want to try to make that argument?

basically I don’t agree at all with these lawyers who think that Wordpress.org has any power whatsoever to dictate what can and cannot be done with their GPL’d software.

Apologies, missed the edit window. I meant to say that they have no power to dictate what can and cannot be down with themes which use their GPL’d software.

I’m the aforementioned Beagle.

I just wanted to come on here because there is clearly a bit of confusion going on.

Firstly, this was an MSN conversation with a friend, so you’ll have to excuse the punctuation etc.

Secondly, I’d like to address what seems to be the main point some people are making, because I think there are really two different points here which I didn’t appreciate until I read what some of you are saying.

The GPL is explicit about what constitutes a derivative work, and themes/plugins are derivative work.

Quite frankly, that doesn’t matter.

I can walk around screaming that every sign made with paint I made is a derivative work. That doesn’t make it true.

The GPL license can say whatever it likes, that doesn’t require the release of any original work as GPL. That’s just the plain fact.

Some people seem to be saying that, “Once you make a Wordpress theme and use it with Wordpress, your theme is GPL’d”.

Err, no, it’s not. It doesn’t matter what the GPL says, Wordpress.org has absolutely no power whatsoever to alter a copyright owned by another person. They can claim whatever they like as derivative works, but unless it actually is a derivative work, then it has nothing to do with Wordpress. Whether it is a derivative work or not is a question of law, not what the GPL says.

Basically, Wordpress claiming any copyright (which is effectively what they’re doing) over your theme or plugin is like saying that Apple has copyright over all Griffin’s accessories ’cause they were made to fit with Apple products.

The GPL does not prevent you from creating and selling themes that are not GPL licensed, but using them in conjunction with Wordpress (or any other GPL’d software) would be a violation of the theme’s non-GPL license.

I think you meant to say a violation of the license with Wordpress.org. This is the other argument I was referring to, and this is an entirely different kettle of fish.

Personally, I think there about thirty million holes in that argument, but I’d need to really sit down with it an nut something out. I don’t think it would stand up in court in New Zealand. Europe may be different, as the basis of European copyright tends to revolve around some kind of intrinsic ownership of the work, rather than the commercial justification used in most common law countries. The DMCA is different again, and the American courts are so erratic it’s hard to say which way they’ll go next.

Anyway, sorry for the ramble, but basically I don’t agree at all with these lawyers who think that Wordpress.org has any power whatsoever to dictate what can and cannot be done with their GPL’d software. It’s my experience that lawyers do a lot of sabre-rattling, and that this is basically what this is.

As someone who’s spent quite a bit of time talking to actual lawyers about the issue, I can say with a high degree of confidence that your friend Beagle should not be relied on for legal advice.

Err, if lawyers always gave the same advice, and had the same opinion, why would anything ever go to court?

Also the only exception to modules not affected by GPL is if they are initated using fork and exec. If Wordpress only calls the constructor of a theme/plugin class then that is a grey area. But this is however not the case with either themes or plugins.

If the theme is useless without the CSS or images one could easily argue that those files are also affected by the GPL. I would say that you cannot make themes or plugins to wordpress that uses wordpress functions or is dependant upon wordpress to function and not have the theme/plugin become GPL.
That is the whole point of the GPL and why you really should use LGPL for your software.
Which you can see if you look at the following perspective.
If you integrate stuff into the TinyMCE editor that is a whole different area since the TinyMCE has a different license than Wordpress (LGPL) you can put a non-GPL licence on the code that TinyMCE interacts with and a GPL licence with a exception on the code that interacts with both Wordpress and the TinyMCE.

But in essence if a theme or plugin calls methods in Wordpress then those files are affected by the GPL.