access to bitfunder assets of a deceased person, how, and who do I talk to?

[lee n. field]

No technical question here, but a substantive one nonetheless.

I am handling the estate of my son, who died this summer. 

He has assets invested with bitfunder.  Bitfunder, I find, is closing up shop soon.  Shares go back to the issuers.

What's the best to contact (ideally) bitfunder?  Failing that, I would need to contact whoever's behind  G-ASICMINER-PT, JAH and ActiveMining?  (There're are three other assets he has, but the value in them is minimal.)