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WordPress Creator GPL Says WP Template Must Be GPL'd 571

An anonymous reader writes "Matt Mullenweg (the creator of open source blog software WordPress), after review by various legal experts, is sticking to his guns that themes and plugins that 'extend' WordPress violate the GPL if they are not themselves distributed under the GPL. Matt has gone so far as to post this on Twitter. According to Matt, the premium template called Thesis should be under the GPL and the owner is not happy about it. WordPress is willing to sue the maker of Thesis theme for not following GPL licensing. The webmasters and Thesis owners are also confused with new development. Mark Jaquith wrote an excellent technical analysis of why WordPress themes inherit the GPL. This is why even if Thesis hadn't copy-and-pasted large swathes of code from WordPress (and GPL plugins) its PHP would still need to be under the GPL."
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WordPress Creator GPL Says WP Template Must Be GPL'd

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  • He has no case (Score:5, Informative)

    by MikeRT ( 947531 ) on Thursday July 22, 2010 @04:03PM (#32995082)

    If he's taken GPL code and put it in Thesis, game over. It's GPL. Period. Whatever he could have argued about API calls is now irrelevant.

    At this point, the only thing I'm curious about is what would happen to WordPress users who start to distribute Thesis without his permission.

  • Re:I don't buy it. (Score:2, Informative)

    by orkysoft ( 93727 ) <orkysoft AT myrealbox DOT com> on Thursday July 22, 2010 @04:04PM (#32995096) Journal


    This is why even if Thesis hadn't copy-and-pasted large swathes of code from WordPress (and GPL plugins) its PHP would still need to be under the GPL.

  • by Annirak ( 181684 ) on Thursday July 22, 2010 @04:12PM (#32995194)

    It really doesn't, actually. The only time that a company would have a problem with this is when they distribute their plugin or theme. Any company which makes a WP template or theme is absolutely not required to open source it unless they distribute it. This means, obviously, that the majority of company-specific plugins and themes are not going to need to be opensourced.

    The only companies which stand to be hurt by this are the ones which have a business model of making wordpress plugins/themes and selling them. Even then, they are not required to stop doing so. The requirement is just to license their software under the GPL and provide source if and only if someone requests it.

    People act like the GPL will kill all software business as we know it, but those who do so clearly haven't even read the license.

  • by AndrewWarner ( 1862164 ) on Thursday July 22, 2010 @04:20PM (#32995290)
    I run, where I did the interview with Matt & Chris. Sorry my site is down. I'm working on it now.
  • by chipbennett ( 1862188 ) on Thursday July 22, 2010 @04:31PM (#32995432)
    The GPL doesn't define "derivative work", nor does the FSF's GPL FAQ; only the Copyright Act does. If the GPL's interpretation of "derivative work" differs from that of the language of the Copyright Act, or of applicable case law, then the GPL's interpretation will not withstand a court challenge. And in fact, the interpretation of FSF/SFLC/Matt Mullenweg/et al that WordPress Themes are inherently derivative of WordPress core, and therefore inherit GPL, runs exactly opposite to relevant copyright case law [].
  • Re:And this folks... (Score:3, Informative)

    by shutdown -p now ( 807394 ) on Thursday July 22, 2010 @04:35PM (#32995514) Journal

    What FUD? GPL is pretty clear.

    How (and even if) GPL applies to dynamic linking - which, in this case, what it really boils down to - is very far from clear. This is especially true for languages where the actual "linking" happens on user side, not on developer side - i.e. anything using a bytecode VM (JIT or no JIT) or a plain interpreter. Such as, well, PHP.

    Yes, the FSF has a well-defined and widely publicized position on this issue, but that is separate from the text of the license as such, and it is not certain if the text really means what they want it to mean.

    The correspondence [] of Stallman with the author of CLisp - where the former argues that mere use of GNU Readline APIs (i.e. invoking a function named "readline" with arguments of specific types) in your code makes it a derived work under the GPL - is a very interesting read in this context.

    Stallman's argument hinges on the claim that the mere existence of Readline means that any program using its APIs is derived work. If you buy into that line of reasoning, then just imagine what the implications would be for any FOSS having to do with clean-slate implementation of proprietary APIs (consider the SCO-IBM case and Wine for a few specific examples; there are many more). I also very much doubt that the court would buy that; indeed, by the end of the email exchange, Stallman also seems to be implicitly acknowledging that, changing his argument to "if you manage to circumvent GPL this way the Evil Proprietarians out there will know they can use it too, and it's BAD BAD BAD, so please do as I say".

    This case seems to be similar. The claim is that the template is GPL'd because it contains calls to functions with names and arguments such that they match the WordPress internal APIs. However, one could do a clean-slate implementation of all those APIs (it wouldn't even have to do anything useful; think mocks), and the template script will happily run on top of that as well. And it doesn't contain any actual WordPress code. So, if it doesn't actually require WordPress to run, why should it be considered a "derived work"?

  • Re:And this folks... (Score:4, Informative)

    by DragonWriter ( 970822 ) on Thursday July 22, 2010 @04:35PM (#32995516)

    What FUD? GPL is pretty clear.

    In this particular case (as apparently there is large cut and paste of code), this seems to be a pretty clear issue; OTOH, the more expansive interpretations often offered of the GPL (including the interpretation that would hold that all templates, etc., for a GPL blogging platform needing to be GPL) is arguably untenable, as many of the things which proponents of this view would demand that the GPL must apply to are not what would otherwise be considered derivative works, and consequently require no license to produce in the first place.

  • by PhrstBrn ( 751463 ) on Thursday July 22, 2010 @04:36PM (#32995536)

    You're confusing LGPL and the GPL. The LGPL has a linking exception, the GPL does not. You cannot distribute code linking to GPL code without using a GPL compatible license. If you link to code distributed under the LGPL, you're fine. The only thing you need to distribute is the the actual library you linked to, if you made any changes, but not the rest of your codebase.

    Wordpress is GPL, so linking to any of the Wordpress codebase requires distributing your code under the terms of the GPL. I don't see how you can make a useful Wordpress theme/template without making a Wordpress call somewhere. Printing out a post, or comment is going to require a function call to some GPLed code.

    I believe the creator is correct, as long as Wordpress remains pure GPL, most non-GPL themes and plugins are going to break the license. It is entirely possible to create a non-GPL plugin, as long as you don't need to make any calls to Wordpress functions or internals.

    Interpreted vs compiled, there is no difference in the interpretation of the license. Linking in an interpreted language is treated the same as linking in a compiled language.

  • Re:He has no case (Score:5, Informative)

    by shutdown -p now ( 807394 ) on Thursday July 22, 2010 @05:07PM (#32996068) Journal

    I apologize for posting incorrect information. Thesis does contain portions of GPL'd code directly copied from WordPress. So what you say is 100% true, regardless of the take on GPL vs dynamic linking and APIs. I somehow managed to read TFA without noticing that bit :( Also see this [].

    However, I still stand by my assertion that any other WordPress theme which did not directly copy WordPress code cannot be reasonably considered a derived work for copyright purposes (and therefore not subject to the GPL), contrary to what WordPress authors claim.

    It's a pity that this case is a GPL violation so blatant that it will never get to the point of debating those (far more interesting) issues in court - in fact, I doubt there will even be a court.

  • Re:And this folks... (Score:3, Informative)

    by DragonWriter ( 970822 ) on Thursday July 22, 2010 @05:24PM (#32996300)

    In other words, it depends a lot whether the non-GPL theme developers ever distributed Wordpress to anyone. If they didn't, they can argue that their themes are not derivatives according to copyright law, and they may have a chance. If they did, they have accepted the GPL's interpretation, and that will be difficult to get around in court.

    Well, except that most of the "definition" of "derivative works" that is contentious isn't in the GPL, but in a section qualified with "we believe" in the FSF's FAQ concerning the GPL, so it isn't part of what people "accept" when they accept the GPL.

  • by Anonymous Coward on Thursday July 22, 2010 @05:33PM (#32996430)

    PHP isn't licensed under the GPL. There is no such requirement.

    WordPress uses the GPL because it is originally a fork of other GPL software, b2.

    For what it's worth, Drupal and Joomla have the same interpretations that themes and plugins/modules are derivative works and thus be GPL -- if distributed. (It only kicks in with distribution.)

  • by salesgeek ( 263995 ) on Thursday July 22, 2010 @06:24PM (#32997092) Homepage

    WordPress themes are simply PHP libraries that WordPress calls when rendering a page. The license status of Wordpress themes are very much dealt with in finality by the GPL, and there is absolutely no question that the PHP files must be licensed per the GPL.

    From the GPL's narrative:

    This General Public License does not permit incorporating your program into
    proprietary programs. If your program is a subroutine library, you may
    consider it more useful to permit linking proprietary applications with the
    library. If this is what you want to do, use the GNU Lesser General
    Public License instead of this License.

  • by mandelbr0t ( 1015855 ) on Thursday July 22, 2010 @06:28PM (#32997130) Journal

    From the lawyer referenced by your link:

    Does a theme, rather than simply calling a WP function, incorporate actual code from WordPress?

    Due to the nature of PHP, yes. The PHP interpreter could not interpret the theme in the absence of WordPress code. It is incorporated in the most explicit manner. The argument that you can apply this same logic to the Linux operating system specifically is not valid, since it is possible to create a stand-alone binary that contains no GPL code. The execution of this binary would never incorporate GPL code; it would only use a system built from GPL code. To prove this, take the non-GPL binary and run it on a commercial UNIX box (there are plenty that provide Linux ELF support). Conversely, take the WordPress theme and run it on an application server that does not have the WordPress source available to it.

    Sure, we're splitting hairs here, but the whole point of the GPL is to protect the intended non-commercial nature of the original project. WordPress was a development given to the public domain in a spirit of community. The creator should not stand by and watch as someone else gets rich from his hard work.

  • Re:And this folks... (Score:4, Informative)

    by B'Trey ( 111263 ) on Thursday July 22, 2010 @06:29PM (#32997148)

    How is dropping a text file in the same folder as wordpress creating something that is "part of WP"?

    It doesn't. I can take a copy of this post and drop it in a WP folder and it's not affected in any way.

    What causes it to be "part of WP" is the fact that the contents of the file in question literally become part of WP. From the last linked article:

    There is a tendency to think that there are two things: WordPress, and the active theme. But they do not run separately. They run as one cohesive unit. They don't even run in a sequential order. WordPress starts up, WordPress tells the theme to run its functions and register its hooks and filters, then WordPress runs some queries, then WordPress calls the appropriate theme PHP file, and then the theme hooks into the queried WordPress data and uses WordPress functions to display it, and then WordPress shuts down and finishes the request. On that simple view, it looks like a multi-layered sandwich. But the integration is even more amalgamated than the sandwich analogy suggests.

    Here is one important takeaway: themes interact with WordPress (and WordPress with themes) the exact same way that WordPress interacts with itself. Give that a second read, and then we'll digest.

  • by Fencepost ( 107992 ) on Thursday July 22, 2010 @08:27PM (#32998382) Journal
    In this particular case it sounds like Thesis is screwed because they're incorporating WordPress code into their theme - game over.

    In the more general case, I think you could make a credible argument that WordPress is designed to look for and utilize external libraries (called "themes") and that just doing so should not make WordPress' license apply to that theme (or plugin). My reasoning there is that if you argue that WordPress incorporating a theme makes the WP license (GPL) apply to that theme, what prevents that theme's license from correspondingly "infecting" WordPress?
  • Re:And this folks... (Score:3, Informative)

    by the_womble ( 580291 ) on Friday July 23, 2010 @02:35AM (#33000194) Homepage Journal

    How is dropping a text file in the same folder as wordpress creating something that is "part of WP"?

    The "text file" contains PHP, including modified versions of code copied from Wordpress itself.

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