Perhaps this is a good time to recall that over a decade ago, ATT sued BSD for coping their UNIX code. As the case progressed, it turned out that ATT had actually copied BSD code into UNIX. The case was settled out of court.
I do not think the present case will turn out to SCO's favor.
On a side note that is what I think is going on here, the code is BSD or GPL that sco put into its UNIX. Probably BSD because I doubt anyone would be dumb enough to put GPL code into their system hide the source and then sue. That or things like
for (x=0; x<10; x++) ....
Are in their code.