If it looks like a Unix, and runs programs like a Unix, and has system calls like a Unix... it must have been copied from our precioussss!!
Never mind that anybody with even a vague knowledge of Unix (and Linux) history, and the reason for POSIX, SUS, and the rest will tell you this is ridiculous nonsense; and where it isn't, it would be very hard to untangle and get a clear claim to anything. Shame on SCOX' management, their own tech people must have told them so. Many times over.
Add the fact that they did not own said "preciousss," as they must have known.
No, there isn't BSD code in Linux (the kernel, that is the subject of SCOX vs IBM). By design: When Linux started, the whole USL vs UCB et al brouhaha was in full swing (if it hadn't, there probably wouldn't be any "Linux" today, but I disgress...), and so Linus and his gang were careful not to use possibly tainted code. Sure, there are broad similarities. Some come from Linus et al studying books on Unix (and operating system in general) design; others come from there just being so many ways of doing some things, and given that a kernel has to do lots of things, by force many will turn out similar; others are just the only (sane) way of getting something done.
If you take a peek at BSD kernel and Linux internals, you will see that they are so radically different that any non-trivial "copying" between the two will be more in the line of ground-up reengineering.