Some 10-20% of the exchange's turnover has to be auctioned as "second-lien", meaning that a bank stands ahead of the investor, in the event that the buyer of the goods goes bust.
Even so, the plan appears to treat second-lienholders better than investors in the main mortgage, because the formerare not required to cut principal when first-lien balances drop.
Of its $95 billion loan book, more than a third is home-equity lines of credit and second-lien mortgages, both much riskier than the typical home loan.