But here's where it gets hairy.  It is assumed that ARM stepped into the fray as a legal obligation to the js because of a patent indemnification clause.  They stepped up against the '584, and the '584 only.  If they had any (perceived) liability regarding the '148 or '336, they would have had no choice but to remain in the fray to defend their legal obligations on those patents as well, IMO.  The Js would have objected to their departure, or failure to defend them against the '148/'336.

Hope this makes sense.

SGE