William M. Griffin

Petro Harvester Oil & Gas LLC operates as an upstream exploration and production company. It focuses on the acquisition, development and operational improvement of oil properties. The company was founded in July 2010 and is headquartered in Plano, TX.

EP Energy Corp. engages in the acquisition and development of unconventional onshore oil and natural gas properties. It focuses on the development of drilling inventory located in the following areas: the Eagle Ford Shale in South Texas, Northeastern Utah in the Uinta basin, and the Permian basin in West Texas. The company was founded on August 30, 2013 and is headquartered in Houston, TX.

Part of KeyCorp, SONAT Exploration Co. is a company that provides petroleum exploration. The company is based in Houston, TX.

Ironwood Oil & Gas LLC is an oil and gas company that operates in the industry. The private company is based in Houston, TX. The company was founded by William M. Griffin.

Black Warrior Methane Corp. produces and sells methane gas. The company was founded on September 1, 1983 and is headquartered in Brookwood, AL.

Part of EP Energy Corp., El Paso Exploration & Production Management, Inc. gathers, markets, processes, stores and transmits gas, petroleum and chemicals. The company is based in Houston, TX.