Torvalds announced this in response to a discussion on the list of Linux developers, which had been started by Jeff Merkey. The former Novell and Canopy Group developer, Merkey is best known in Linux circles for his attempt to buy a non-GPLed version of the Linux code.
In response to the discussion that followed, Alan Cox, the lead maintainer of the production version of Linux, said, "What finally happens is going to depend almost entirely on whether the GPL v3 is a sane license or not and on consensus, and it is way too early to figure that out."
After still more discussion,Torvalds stepped in.
First, he said, "The Linux kernel has always been under the GPL v2. Nothing else has ever been valid."
Torvalds then explained that some of the confusion has come about because people confuse some of the GPLs explanatory text with the license itself.
"The Version 2 of the License, or (at your option) any later version language in the GPL copying file is not—and has never been—part of the actual License itself. Its part of the _explanatory_ text that talks about how to apply the license to your program, and it says that if you want to accept any later versions of the GPL, you can state so in your source code."
Torvalds went on, "The Linux kernel has never stated that in general. Some authors have chosen to use the suggested FSF (Free Software Foundation) boilerplate (including the "any later version" language), but the kernel in general never has."
Therefore, "The default license strategy is always just the particular version of the GPL that accompanies a project. If you want to license a program under any later version of the GPL, you have to state so explicitly. Linux never did."
Torvalds then spelled out his position clearly: "The Linux kernel is under the GPL Version 2. Not anything else. Some individual files are licensable under v3, but not the kernel in general."
It is a mistake, Torvalds said, to "think v2 or later is the default. Its not. The default is to not allow conversion."
Torvalds added, "I dont think the GPL v3 conversion is going to happen for the kernel, since I personally dont want to convert any of my code."
Or, in fact, "Conversion isnt going to happen," he said.
Notably, Torvalds is not a real fan of the GPL 2 license. In a 2004 eWEEK interview, the Finnish Linux developer said, "I dont think the GPL is perfect, and one of my issues has been how ver-bose it is. Another is just the politics involved, which I havent always enjoyed."
Still, he said, "Nothing is ever perfect. So while I may have some niggling concerns with the GPL, they are in the details, and in the end, I actually think that the GPL simply is the best license for the kernel."
Other Linux developers, such as the Debian Project community of programmers, are more positive about the GPL 3 draft. Still, they also have questions about how the GPL 3 and DFSG (Debian Free Software Guidelines) will co-exist.
There are also some rumblings in the business community about GPL 3s anti-DRM (digital rights management) clauses, but no company has yet taken a real stand against these proposals.
Given that Linuxs core, easily the most popular GPLed program in the world, isnt going to be covered by the GPL 3 if Torvalds has his way, these points may be moot for many developers.