Judges always take sides - they are humans after all. Their job is it to ignore that and let "justicia" decide. Given how ridiculous Oracle's claims are, he has to look after it that ridicule does not take over and damages the trial.. I don't think he really sides with Google, he has probably just adopted his programmer's world view in this case, and sees how ridiculous the claims really are. In many other tech cases (ahem, copyright infringement) judges are not as competent and can't imagine the real implications of their rulings.