Antero Resources LLC (NYSE: AR) is a Denver, Colorado-based independent oil and gas company focused on the exploration and exploitation of unconventional natural gas resources in the United States. Since February 2003, Warburg Pincus has led multiple rounds of equity financing totaling nearly $1.5 billion of capital to Antero. Following the sale of its Barnett Shale assets to XTO Energy in April 2005 for more than $1 billion, the company continued to build and develop sizable positions in low-cost unconventional domestic natural gas plays with a particular focus on the Appalachian Marcellus and Utica Shales. The management team remained with Antero following this sale and continues to explore and develop properties in Appalachia with financial backing led by Warburg Pincus. The management team is led by CEO Paul Rady and President Glen Warren, each of whom have long and distinguished track records in the oil and gas industry at organizations including Barrett Resources Corporation and Pennaco Energy. The company has concentrated its efforts in the core liquids-rich region of each play and now boasts more than 325,000 net acres in the Marcellus Shale and more than 100,000 net acres in the Utica Shale. Antero also has dedicated significant resources to the build-out of the associated infrastructure requirements including natural gas gathering and processing as well as a proprietary fresh water pipeline system currently under construction. Since completing the divestiture of its sole remaining non-Appalachian asset at the end of 2012, Antero has steadily increased activity in its core areas. In October 2013, Antero completed an IPO on the New York Stock Exchange.