<P> A company that has either upstream or downstream operations, but not both . Examples include Anadarko, Sunoco, Phillips 66, ConocoPhillips, and Murphy . </P> <Ul> <Li> Oil Service Company: </Li> </Ul> <Li> Oil Service Company: </Li> <P> A company that provides products and / or services to the oil and gas industry . Usually a combination of labor, equipment, and / or other support services . Examples include Baker Hughes, a GE Company, Haliburton, and Schlumberger . </P>

What is upstream and downstream flow in oil and gas