GenOn Energy, Inc., based in Houston, Texas, United States, was an energy company that provided electricity to wholesale customers in the United States. The company was one of the largest independent power producers in the nation with more than 14,000 megawatts of power generation capacity across the United States using natural gas, fuel oil and coal. GenOn Energy is headquartered in the Reliant Energy Plaza in Downtown Houston. The company, formerly known as RRI Energy, acquired Mirant on December 3, 2010. The corporate names and logos of both RRI Energy and Mirant were retired. NRG Energy completed its acquisition of GenOn Energy in December 2012 for $1.7 billion. GenOn's stock ceased trading and was exchanged for NRG stock. History The company was originally known as Houston Industries (), and Houston Lighting & Power was its subsidiary. In August 1996 HI closed on a merger with NorAm Energy Corp, a natural gas utility. The combined company, as of 1997, had assets of $18 billion and annual revenues of about $9 billion. By November 1997 there was a published report stating that the company wished to acquire Central & South West Corp. HI declined to comment. In 1999, Houston Industries changed its name to Reliant Energy and its new NYSE symbol was REI. It was scheduled to begin trading under REI on February 8, 1999. In 2002, Texas deregulated the electricity market and Reliant then competed against other energy companies like Direct Energy and TXU Energy. At this time, Reliant Energy also separated into two publicly traded companies: Reliant Resources, Inc. and CenterPoint Energy, Inc. (). When the state of Texas deregulated the electricity market, the former HL&P was split into several companies. In 2003 HL&P was split into Reliant Energy, Texas Genco, and CenterPoint Energy. CenterPoint Energy was created when Reliant Energy merged with an indirect subsidiary of CenterPoint Energy, Inc. As a result of the merger, Reliant Energy shareholders received one share of CenterPoint common stock in exchange for each share of RRI common stock they held before the merger. A regulated utility, CenterPoint Energy became one of the largest U.S. energy delivery companies, serving 4.7 million metered customers. In late 2002, CenterPoint distributed the stock of Reliant Resources, Inc. to CenterPoint shareholders. This spin-off created Reliant Resources with a strategy to provide competitive wholesale and retail energy service under the Reliant Energy brand. Its businesses included power generation and