++++ Competition ° Agreements, decisions and concerted practices ° Prohibition ° Block exemption ° Exclusive purchasing agreements ° Regulation No 1984/83 ° Service-station agreement concluded before the accession of Spain and Portugal for an indefinite period or for more than 10 years ° Benefit of exemption ° Conditions (EEC Treaty, Art. 85(3); Commission Regulation No 1984/83, Arts 12(1)(c) and 15(3) and (4))