In the paper, the fundamental question is under what conditions loyalty discounts and rebates adopted by a dominant firm cause anti-competitive effects. Fidelity schemes, although extremely frequent in the market, if applied by a dominant firm, are likely to be judged as illegal per se, as...

In order to fight collusive behaviors, the best scenario for competition authorities would be the possibility to analyze detailed information on firms' costs and prices, being the price-cost margin a robust indicator of market power. However, information on firms' costs is rarely available. In...