Windows 95 contained more actual UNIX code (TCP stack) than Linux does...
http://www.linuxinsider.com/perl/story/32719.html
History may give us a place to start. Everybody knows Unix started at what was then AT&T Bell Labs and went through two enormous growth phases, the first at Berkeley in the early 1980s and the second at Sun 10 years later, but surprisingly few people know where Linux came from.
The current kernel is fundamentally the work of Linus Torvalds and people he recruited into the kernel development and maintenance process, but the kernel he started with -- Andrew S. Tanenbaum's Minix -- was unambiguously described by its author as "an open source Unix clone."
So Linux is actually a work based on a clone of UNIX, using GNU software (which is *not UNIX*)
I don't believe Linus made a secret of the fact that he set out to recreate Unix on an x86. Did he use Unix code, probably not, did he recreate the behavior of Unix? Definately. Is SCO and MS full of BS? Definately, did Linus create a new wonderful OS? No, Linux is Unix on the x86 without the AT&T code. Just like FreeBDS which at least admits it is a Unix OS.
Your words: but the kernel he started with -- Andrew S. Tanenbaum's Minix -- was unambiguously described by its author as "an open source Unix clone."
I thought that basic copyright law included the principle that one
can NOT
copyright ideas,
only their particular, specific expression in certain words and word patterns or, in this case,
in certain code and code patterns????