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The way this is written seems to imply that the GPL has a say on what constitutes a derivative work. This may not be what the author intended, but it is a frequent misapprehension.
The correct way to say this would be 'what constitutes a derivative work under *copyright law*?' - the license in question is irrelevant.
WordPress, themes, and derivative works
Posted Jul 28, 2010 17:28 UTC (Wed) by dwheeler (guest, #1216)
"The correct way to say this would be 'what constitutes a derivative work under *copyright law*?' - the license in question is irrelevant."
Technically true, but in practice, what matters is both what copyright law says, and what the license says.
Fundamentally, copyright law defines the "upper bound", in this case, what can or can't be restricted by law.
But within this upper bound, a license can permit certain actions that the copyright law would allow to forbid.
And as a practical measure, laws are often fuzzy; the exact boundary of "derivative" is sometimes unclear, and few people are willing to go to court over such interpretations... so if there is a lack of clarity, a license will often have a practical effect.
There are lots of proprietary libraries that have run-time fees, and their legal theory about derivative works is exactly the same as the GPL's view about linking to libraries.
I don't know if a court case has ruled specifically on that point, but given the widespread practice, I believe a court is likely to accept the interpretation that an executable that links to a library is, in total, a derivative work of that library.
After all, many people have been making that assumption for decades.
Posted Jul 28, 2010 22:08 UTC (Wed) by anselm (subscriber, #2796)
According to copyright law, only the copyright holder of a library (proprietary or free) is entitled to distribute the library code, so in the »proprietary case« the application author must pay the copyright holder a run-time fee to be allowed to pass a copy of the library along with their application. In this case, the question of whether the application is a »derivative work« of the library or not is immaterial, since the fee serves to compensate the (library) copyright holder for letting someone else (the application author) do something which would otherwise be the copyright holder's prerogative, namely making and distributing copies of the proprietary library.
The derivative-work issue only becomes a problem with the GPL, where there is already blanket permission in the license to pass copies of a library along with an application (albeit with strings attached concerning licensing and publication of source code, etc.). The question here is what combining an application with a GPLed library does to the licensing options for that application, not how the library copyright owner is to be compensated for the use of their actual code, which is what the run-time fees are about. I am not a lawyer in any way, shape, or form but would venture to guess that the legal theory covering this (such as there exists) is completely different from that dealing with run-time fees for libraries.
Posted Jul 29, 2010 22:53 UTC (Thu) by giraffedata (subscriber, #1954)
But who says the recipient doesn't get the library from someone else? The library author gives Mary a copy of his library, then the application author gives Mary a copy of the application.
It seems to me the derivative work issue is no more an issue with GPL-licensed stuff than with any other licensed stuff.
I agree with nye that people should keep clear in their minds what is copyright law and what is GPL. (Hint - if it stops you from doing something, it's not GPL. GPL only adds to what you can do). That prevents them from imagining that the author can control more than he really can.
Posted Jul 30, 2010 1:50 UTC (Fri) by vonbrand (subscriber, #4458)
True, but in the case of propietary stuff you pay for the permission to redistribute the library (and perhaps also for the right to create a derivative work to be distributed with it). In the GPL case the only point that matters is the second one, which is very much irrelevant in the propietary case.
Posted Jul 30, 2010 7:12 UTC (Fri) by anselm (subscriber, #2796)
You're saying the derivative work issue is specific to GPL because without GPL the application author couldn't distribute his application without the permission of the library author anyway, because the application is no good without the library and he would need the permission of the library author to distribute the library.
No, I don't. I said that according to copyright law only the copyright holder gets to distribute their code, and that vendors of proprietary libraries may charge run-time fees in order to allow others to do it too.
Application authors tend to take advantage of that sort of arrangement for the convenience of the users of their code. Whether that makes the application a "derived work" of the library is a non-issue in this case;
the library is presumably sold in order to be incorporated in applications, and end users typically don't get to redistribute the code in question to yet other people.
With a GPLed library, permission to distribute is already part of the library's license, and the authors of the GPL are jumping through hoops to try to enforce specific licensing conditions on the distribution of code that uses that library, which is an entirely different ball-game from the proprietary case.
Posted Jul 30, 2010 10:03 UTC (Fri) by marcH (subscriber, #57642)
That's circumvention, it's forbidden by the DMCA.
Posted Jul 30, 2010 15:41 UTC (Fri) by mpr22 (subscriber, #60784)
Posted Jul 29, 2010 10:39 UTC (Thu) by hummassa (subscriber, #307)
Now, if _the_ Pierce themes are derivative works of WP, that is one thing that I didn't analyse myself. They can be (especially if lots of non-trivial, can-be-done-differently-but-wasn't boilerplate code is involved). But I have a serious problem with the linking myth.
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