An opaque inventory is the market of selling unsold at a discounted price. The inventory is called "opaque" because the specific suppliers (i.e. hotel, airline, etc.) remain hidden until after the purchase has been completed. This is done to prevent sales of unsold inventory from cannibalizing full-price retail sales. According to TravelClick, the opaque channel accounted for 6% of all hotel reservations for major brands in 2012, up 2% from 2010.