WAntar (company)
WBataafse Petroleum Maatschappij
WCampsa
WCommonwealth Oil Refining Company
WDome Petroleum
WEesti Kiviõli
WEsimene Eesti Põlevkivitööstus
WHydro Oil & Gas
WIraq Petroleum Company
WNew Consolidated Gold Fields
WRoc Oil Company
WSaga Petroleum
WStatoil Fuel & Retail
WSupertest Petroleum
WWintershall