It is not at all unusual for a party to accompany his attorney to such a hearing. Unless he is called upon to take part, which would rarely occur, his presence isn't "necessary" --- however, he has a vested interest in the outcome, which often creates a keen sense of interest in seeing what goes on in the courtroom. So, while I don't know for sure, I would conclude that this is why Mr. Moore chose to be present. It is also possible that he felt he could learn something of practical or technical value to the case from listening to Barco's attorneys. He might also have wanted to make his presence known to Dan Leckrone.
FYI, court hearings are usually open to the public, so anyone can attend. Mr. Moore also attended the Markman hearing in the J3 cases, as did David Pohl, Eric Swartz, Carl Johnson, and several shareholders such as Brian and me. All of us, of course, were affiliated in some way or another with the Company, but, quite literally, anybody could have walked in off the street (as long as they were dressed appropriately and were able to pass through security).
Hope this helps.
