It's widely believed that M$ bankrolled the lawsuits originally but withdrew their support when it became pretty clear that SCO wasn't going to win much, if anything. Of course this may just be the conspiracy theorists at work.
It's an incredibly complex story, and Groklaw has been following it all the way, but you need to be a lawyer with several ice packs on your head to take in all the detail.
Novell are generally reckoned to be good guys in the Linux world, although their recent licensing deal with M$ didn't go down so well.