In the same statement they say that they've have a very good collaboration with Red Hat so far. If I had to guess, this was a commercial decision made by IBM. The people from Red Hat never showed any tension to act against anyone relying on their work. But if the Big Blue can't see the Big Bucks, they can now force their will over their people of Red Hat, whom they own; it's their property now...
I was hoping that Red Hat could inspire IBM to become again the giant there were before 1980s but apparently my hopes are about to evaporate.