Opty: Having worked for a large multinational corp. for many years, regularly interfacing with financial sr. mgt. and legal dept., it seems to me possible but not very likely that heavy buying is occurring from the litigants.  The company's treasury dept. would likely evaluate a possible stock purchase, and PTSC's BB status would probably scare them.  However, some big companies often make small (or large) incubator-type investments in start-ups, so it is not beyond the pale.

As for why the case has not yet been settled, who knows?  Could be hubris or stubbornness, bad legal advice (inside or outside counsel), or simply a desire to play the string out further, see what the Markman ruling brings, and then reevaluate.  Still lots of time before the actual trial.  JMHO and I know less than SGE1!!!