[asciilifeform]

AFAIK it's still owned by one John Mallery, a wealthy MIT prof with military and intelligence establishment connections.

My favourite "conspiratorial" hypothesis concerning this question is that the Symbolics IP was ordered to be perma-buried for "national security" reasons (as it threatens to make practical systems with capabilities much superior to today's state of the art, but running on early 1990s IC fab processes) and that Mallery (who, per rumour, purchased the IP for next to nothing via a backroom deal) was the designated undertaker.

AFAIK it is still unknown whether the chip die masks, source for (the parts not included on the tapes/CD) os/compiler/IC workflow -- was even preserved to this day.