Linux GPL and binary module exception clause?

Kendall Bennett
2003-12-03T21:30:43Z

Hi All,

I have heard many people reference the fact that the although the Linux
Kernel is under the GNU GPL license, that the code is licensed with an
exception clause that says binary loadable modules do not have to be
under the GPL. Obviously today there are vendors delivering binary
modules (not supported by the kernel maintainers of course), so clearly
people believe this to be true. However I was curious about the wording
of this exception clause so I went looking for it, but I cannot seem to
find it. I downloaded the 2.6-test1 kernel source code and looked at the
COPYING file, but found nothing relating to this (just the note at the
top from Linus saying user programs are not covered by the GPL). I also
looked in the README file and nothing was mentioned there either, at
least from what I could see from a quick read.

So does this exception clause exist or not? If not, how can the binary
modules be valid for use under Linux if the source is not made available
under the terms of the GNU GPL?

Lastly I noticed that the few source code modules I looked at to see if
the exception clause was mentioned there, did not contain the usual GNU
GPL preable section at the top of each file. IMHO all files need to have
such a notice attached, or they are not under the GNU GPL (just being in
a ZIP/tar achive with a COPYING file does not place a file under the GNU
GPL). Given all the current legal stuff going on with SCO, I figured
every file would have such a header. In fact some of the files I looked
at didn't even contain a basic copyright notice!!

Regards,

---
Kendall Bennett
Chief Executive Officer
SciTech Software, Inc.
Phone: (530) 894 8400
http://www.scitechsoft.com

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