It sort of looks to me like these new platforms were created to provide liquidity for funds to sell their stock from PP into the market without showing a sell in the que. They work like vampires stealing trades from unsuspecting investors thinking that they are the lead "ask" order... Since the transaction is not deseminated the unsuspecting lead on the ask does not even know that a trade occured at his selling price.
He didn't even know he'd been screwed..... ZZZZzzzzzzZZZzzzzZZzzzzzz