Because there was so little transparency, it often was unclear who owed (or would owe later) what to whom. Most of their liabilities were off balance sheet; so also most of their assets.
As someone put it, the shadow banking entities were characterized by a lack of disclosure and information about the value of their  BIS central bankers’ speeches  1  assets (or sometimes even what the assets were); opaque governance and ownership structures; little regulatory or supervisory oversight of the type associated with traditional banks; virtually no loss-absorbing capital or cash for redemptions; and a lack of access to formal liquidity support to help prevent fire sales.