German regulator warns petrol station oligopoly

-- BP's (BP.L: Quote, Profile, Research) Aral, Exxon Mobil's (XOM.N: Quote, Profile, Research) Esso, ConocoPhillips' (COP.N: Quote, Profile, Research) Jet, Royal Dutch Shell (RDSa.L: Quote, Profile, Research) and Total (TOTF.PA: Quote, Profile, Research)...