Baker Hughes is an international industrial and oil field service company.
Chevron is an integrated energy and technology company.
Valero Energy is an independent petroleum refining and marketing company.
Marathon Petroleum Corporation (MPC) is a petroleum refiner, marketer and transporter.
Hess is a global independent energy company primarily engaged in the exploration and production of crude oil and natural gas.
Noble Energy is an independent oil and natural gas exploration and production company.
Apache Corporation is an independent energy company that explores, develops and produces natural gas, crude oil and natural gas liquids.
ConocoPhillips is an independent exploration and production company, based on proved reserves and production of liquids and natural gas.
Newpark Resources is a worldwide provider of value-added drilling fluids systems and composite matting systems used in oilfield and other commercial markets.
Marathon Oil Corporation is an independent oil and natural global exploration and production company.
Concho Resources is an independent oil and natural gas company engaged in the acquisition, development and exploration of oil and natural gas properties.
Pioneer Natural Resources is a large independent exploration and production company with operations in the United States.