Exxon Mobil Corporation explores for and produces crude oil and natural gas in the United States, Canada/Other Americas, Europe, Africa, Asia, and Australia/Oceania.
Chevron Corporation, through its subsidiaries, engages in integrated energy, chemicals, and petroleum operations worldwide.
ConocoPhillips explores for, produces, transports, and markets crude oil, bitumen, natural gas, liquefied natural gas (LNG), and natural gas liquids worldwide.
Schlumberger Limited supplies technology for reservoir characterization, drilling, production, and processing to the oil and gas industry worldwide.
Marathon Petroleum Corporation, together with its subsidiaries, engages in refining, marketing, retailing, and transporting petroleum products primarily in the United States.
Valero Energy Corporation operates as an independent petroleum refining and ethanol producing company in the United States, Canada, the United Kingdom, Ireland, and internationally.
EOG Resources, Inc., together with its subsidiaries, explores for, develops, produces, and markets crude oil and natural gas.
Anadarko Petroleum Corporation engages in the exploration, development, production, and marketing of oil and gas properties.
Occidental Petroleum Corporation, together with its subsidiaries, engages in the acquisition, exploration, and development of oil and gas properties in the United States and internationally.
ONEOK, Inc., together with its subsidiaries, engages in the gathering, processing, storage, and transportation of natural gas in the United States.
The Williams Companies, Inc. operates as an energy infrastructure company primarily in the United States.
Baker Hughes, a GE company provides integrated oilfield products, services, and digital solutions worldwide.
Pioneer Natural Resources Company operates as an independent oil and gas exploration and production company in the United States.