As of September 9, 2009, PowerShares DB Crude Oil Double Long ETN has gone out of business. It is an exchange traded note launched by Deutsche Bank AG (London). The note seeks to track twice the monthly performance of the Deutsche Bank Liquid Commodity index - Optimum Yield Crude Oil Excess Return and the DB 3-Month T-Bill Index. The oil index represents the commodity markets. It comprises of future contracts on crude oil. The Index takes long positions. PowerShares DB Crude Oil Double Long ETN was formed on June 16, 2008 and is domiciled in the United States.