[netbsdusers]

> you can technically look at some of the code that comes with it, but you can't modify it.

This is equally true of the GPLv2. The attempt to close this loophole - Tivoisation as Stallman called it - only won him a lot of scorn from Linux land and a refusal to adopt the GPLv3!

[MangoToupe]

Fair; I suppose that concern is technically beyond copyleft.