[Discuss] interpretation of GPL 's combined derivative works

[tmetro+blu at gmail.com (Tom Metro)]

Edward Ned Harvey wrote:
> ...where do you draw the line, for a "derivative work?"  Static
> linking?  VMDK files?  Laptops?

Not that anyone is still following this thread, but...I believe the
answer, per the spirit of the GPL, if not the letter, is that if the GPL
portions of the released work can be separated, modified by the end
user, and recombined, it's compliant.

So I get my laptop from Dell with Ubuntu pre-loaded and an Nvidia
proprietary driver installed, I can obtain the driver and Ubuntu source
from Dell, modify Ubuntu, reinstall it, and use the modified combined work.

Obviously interpretation is controversial in this area, so you have
other situations where the proprietary bits (Nvidia drivers, Adobe
Flash, etc.) are not distributed with the GPL code at all, but instead
downloaded.

And then there is the classic TiVO example, where the source was made
available (I'm assuming with some proprietary blobs, as well), but it
was digitally signed with a private key, so modified versions could
never be ran on the hardware, thus motivating GPLv3.

It's really not that fruitful to speculate on how broadly you can
interpret the GPL's description of a combined derivative work, as the
license is plenty old enough that the practical answer has been
established by case law.

So yeah, file boundaries can be argued to be meaningless, but the
reality is that Linksys and all the other router vendors didn't get sued
out of the Linux router business just because they distributed Linux
with proprietary Broadcom blobs. (They did, however, get sued for not
making the modified GPL source available.)

 -Tom

-- 
Tom Metro
Venture Logic, Newton, MA, USA
"Enterprise solutions through open source."
Professional Profile: http://tmetro.venturelogic.com/