Why SuSE was bought
I think most of you already know the answer from the sites that are making a living from it. Novell still has some intellectual property rights over the Unix name and concept Unix, almost as much as SCO, the infamous company which pretends that Linux is copying Unix, breaching their rights. If an Unix copyright owner is distributing Linux under GPL, Linux is out of SCO’s legal questions. Why IBM was investing in it? Because this give them property over Unix , teh syystem that thy use and sell for the big irons, the very expensive mainframe computers.
What am I going to tell you, more than you already knew?
As I heard (and it is possible to be wrong here, but it is SCO’s fault), the proof of copying from Unix was done and SCO shown (to selected public) even comments that are identical in Linux and Unix sources. They sued IBM, because that code in Linux was added by the IBM. The open-source community loved IBM and encouraged the collaboration over sensitive topics like KDE, that strived to make Linux more than a command prompt. But in the background, the mainframe got the alternative OS, Linux, that made them too something more than a command prompt. IBM makes profit out of this move, and they do that on the work of the naive open source movement.
By paying 200 millions, IBM just fixed their shameful copy/paste and kept the friendship with the Open Source people.