The PPS appreciation isn't for 'no reason'. But your great DD should have seen that. And you're worried about a form 15? Which they may have filed many years ago. How do you know they didn't? They were filing 8k's until the 90s per SEC records. Don't spread assumptions as facts. And it's not a shell... Seriously, didn't you look at all?! Something tells me you have a bid in ;) Good luck!
"One of the funny things about the stock market is that every time one person buys, another sells, and both think they are astute." - William Feather.