BP plc








Chevron Corporation







China Petroleum & Chemical Corp.







ConocoPhillips








  Ecopetrol SA







  Encana Corporation








Eni SpA









  Exxon Mobil Corporation








  Occidental Petroleum Corporation








Petrobras Argentina SA







PetroChina Co. Ltd.







  Rose Rock Midstream, L.P.







 Sasol Ltd.







  Statoil ASA







Total SA