OBSI.HRPT? CPA? C'mon - what's really "legal" on that market? - you've gotta be fucking kidding me with that argument to close trading down. (those defaulted assets should move, to where inexperienced investors can't see them).
Personally, I think that trading in defaulted assets should have been halted from the outset but sooner or later the Bitcoin world is going to need to come to grips with the concept of "sophisticated investors" and offer certain investments only to those who can meet certain income/asset benchmarks. Of course this requires verifying people's real life financial information so it's likely to be unpopular with many. And people are still going to create pass-throughs to high risk offerings, but it's a step towards making those who promote high risk investments more accountable.
People trade in defaulted assets all the time. Typically, they move off major exchanges and onto sketchier ones, or to OTC, but trade they do. (and make lots of money doing it, I might add...thus why I was a little miffed when these stopped trading....I made my rent trading ppt bonds back & forth this month. Would have been nice to not have that flow stopped - though pirate's message re: the 12th kinda killed the market)
I am not a fan of having to have accredited investors, in the typical legal sense. I like the MPEx way of weeding people out, though. Some technical skill/determination & a few coins. I'm also not a fan off verifying my financial information. It just irritates me every time. If I had to be an accredited investor to trade in what I do trade in now, I couldn't do it. That's a huge attraction for me for bitcoin. Most people shouldn't do such things, but I'm not a fan of having to have the government protect you from your own dumb ass.(maybe I'm a fan of it protecting you from some other dumbass...but not yourself - you do that, or you put the finger on the stove and get burned.)