International Coal Group, Inc. (ICG), is a company headquartered in Teays Valley, West Virginia that was incorporated in May 2004 by WL Ross & Co for the sole purpose of acquiring certain assets of Horizon. ICG eventually operated 12 mining complexes in Northern and Central Appalachia (Kentucky, Maryland, and West Virginia) and one complex in the Illinois Basin. In November 2005 ICG had a stock offering on the New York Stock Exchange. In 2011 ICG became a subsidiary of Arch Coal, Inc in 2011.