Spouting off cases as if they might be precedent, or represent the law of the land in a contract dispute should be left to attorneys arguing before judges. Someone may read your poorly thought out and dangerous legal opinion and act on it with dire and expensive consequences in the future.
"Poorly thought out and dangerous legal opinion"? Are you referring to my comments in this thread, or in my original blog post in which I explained my reasoning?
Here's why you are completely and utterly wrong to base your theory on your trinity of copyright cases:
Not three, but five. You left out Sega and Sony.
Gallob v. Nintendo - This case legalized the Game Genie. It would be tough to explain how a game genie works just like a word press theme, mainly because what amounts to an idiot proofed hardware debugger isn't the same thing as blogging software.
One doesn't need to explain how the Game Genie "works just like a [WordPress] theme". That's not the point of the reference. Rather, the point of the reference (and the reason the ruling is germane) is that the court ruled that that Game Genie, which is wholly dependent upon the Nintendo-copyrighted Nintendo gaming console, was not a derivative work of that system. One of the main points of Galoob is that dependent does not equal derivative.
Brown Bag - I'm assuming you are talking about the look and feel lawsuit and not the adult toy lawsuit. This case was about the Brown Bag feeling that their GUI was similar to a Symantec product (I seem to recall it was outlining software). The GUIs were so different that the judge looked at the screens of both and immediately (as in pre-trial summary judgment motion) ruled in the defendant's favor.
Brown Bag is germane in that it moves legal precedent away from the previous tendency of broad-construction determination of "derivative work", culminating in Whelan, toward a much narrower construction. Where Whelan considered the overall purpose of a computer program, Brown Bag set the precedent for digging much deeper. Essentially, the abstraction level changed with Brown Bag. Quoting from myself: Brown Bag appears to indicate that an analytical dissection of WordPress and a WordPress Theme would have to result in some tangible similarity of copyrightable content. This dissection is further clarified and defined in subsequent court rulings. (Which brings us to Altai.)
Computer Associates v. Altai is a case about employee misappropriation of code where somoene left CA and went to Altai, and took a program with them. By the time CA sued, Altai had re-written the sofware and removed all CA code. The court ruled that the current version Altai's product did not infringe and that CA had sued the wrong party for the initial version - Altai was not liable (because the infringement was long gone in the porduct), but the former CA employee who stole the code might be (the employee was never sued - probably blood from a stone).
Altai is germane, because its process for determination of derivative-work copyright infringement has been used in essentially every subsequent software copyright infringement case. No court since the Altai ruling has used a Whelan-type construction. Again quoting from myself: Altai has become the controlling precedent in defining the method for determining whether one computer program infringes another’s copyright, superseding the precedent set by Whelan. The Altai court established the Abstraction-Filtration-Comparison test, which analyzes increasingly lower levels of abstraction, filters out non-copyrightable code, and then performs a comparison of what remains. With respect to WordPress, this process would almost certainly filter out the WordPress function calls and filter/action hook references as merger/scenes a faire processes and methods necessary to implement interoperability.
I would probably fire an attorney that tried to convince me to use the set of irrelevant cases that you are citing as precedent. More than likely you would end up losing on pretrial motions because these cases are simply not relevant, and the judge would see that the plaintiff is simply trying to bamboozle the court. It would be embarrassing, expensive and probably waste a lot of everyone's time.
Fire away, then. But before you do so, I would advise you to at least try to find any relevant case law that refutes the above arguments. I couldn't.
Now on to your use of language to advocate your position. You say the words "derivative work" and "incorporation" mean something very specific in copyright law. They do. But courts are not restricted to using only Black's to understand the English language.
Of course they're not so restricted. The way that the Copyright Act was designed was to provide a general framework, which would be further clarified by the courts. It is not the dictionary upon which a legal argument is based, but rather precedent case law. I've cited five precedents; I have yet to see anyone cite even a single precedent that refutes the conclusions based on those precedents.
At the end of the day, though, one of the legal (meaning from the law dictionary) definitions of "incorporation" seems to fit the context of the GPL perfectly:
"To cause to merge or combine together into a united whole."
Which perfectly describes the combination of a WordPress theme with WordPress itself.
To my knowledge, nobody has argued against the assertion that running a WordPress Theme with WordPress constitutes a combination of WordPress + Theme, and therefore that combination represents a derivative work. However:
1) That combination is made not by the Theme Developer, but rather by the End User. The Theme Developer, in developing the Theme, does not make and distribute the combination you describe.
2) That combination exists only in memory. There is a seemingly reasonable argument (one I've not addressed/researched, nor do I really care to) that merely aggregating WordPress and a WordPress Theme on a web server does not represent a permanent-form incorporation, since the combination only happens in memory, by the PHP interpreter.
The GPL is one of the best thought out license agreements out there. It does what it's supposed to do. It's been around for a long time and has generally held up when litigated.
Personally, I think that it's not often litigated because the risk/reward isn't great enough, either for the copyright holder or the alleged infringer. Thus, most GPL-related copyright infringement issues are settled or handled out of court.
The fact that it is not often litigated speaks volumes: it's unwise to litigate against such a clear contract that so clearly expresses the author's willingness to share, so long as you share, too.
Interesting that you call the GPL a contract. It is the contention of the FSF - or, at least Eben Moglen - that the GPL is a copyright license only, and explicitly not a contract. Also, there are several people who believe that the GPL isn't on as secure enforceability footing as you would imply. I hazard no guess either way on that matter. I just think it's prudent to point out that there is no consensus on enforceability of all aspects of the GPL.