Natural Resource Partners (NRP) makes money from coal without getting its hands dirty. Rather than mining the coal itself, NRP leases properties to coal producers. The company's properties -- mainly in Appalachia but also in the Northern Powder River Basin and the Illinois Basin -- contain proved and probable reserves of about 2.4 billion tons of coal. NRP was formed as a partnership between WPP Group (Western Pocahontas Properties, New Gauley Coal, and Great Northern Properties) and Arch Coal. Arch Coal has sold its stake in NRP but remains one of the company's top lessees, along with Alpha Natural Resources. Chairman and CEO Corbin Robertson controls about 35% of NRP, primarily through WPP Group.