Market Entry, Fighting Brands, and Tacit Collusion: Evidence from the French Mobile Telecommunications Market

We study a major new entry in the French mobile telecommunications market, followed by the introduction of fighting brands by the three incumbents. Using an empirical oligopoly model, we find that the incumbents’ fighting brand strategies are difficult to rationalize as unilateral best responses. Instead, their strategies are consistent with a breakdown of tacit semi-collusion: before entry, the incumbents could successfully coordinate on restricting product variety to avoid cannibalization; after entry, this outcome became harder to sustain because of increased business stealing incentives. Consumers gained considerably from the added variety and, to a lesser extent, from the incumbents’ price responses. (JEL L13, L21, L96, M31)

14. Horizontal agreements (2): oligopoly, tacit collusion and collective dominance

Oligopoly exists where a few firms between them supply all or most of the goods or services on a market without any of them having a clear ascendancy over the others. The purpose of this chapter is to examine whether oligopoly presents a particular problem for competition policy and, if so, how that problem should be overcome. The chapter discusses the theory of oligopolistic interdependence and how oligopolies can lead to a well-known problem for competition law and policy: oligopolists are able, by virtue of the characteristics of the market, to behave in a parallel manner and to derive benefits from their collective market power without, or without necessarily, entering into an agreement or concerted practice of the kind generally prohibited by competition law. This phenomenon is known in economics as ‘tacit collusion’ and is the result of each firm’s individual and rational response to market conditions. The chapter identifies possible ways of dealing with the ‘oligopoly problem’, before considering the extent to which Articles 101 and 102 can be used to address that problem. The chapter also discusses UK law and, in particular, the possible use of the market investigations to address market failure that may arise in oligopolies.

Tacit Collusion with Consumer Preference Costs

When consumers have preference costs, two opposing effects need to be assessed to analyse the incentives of firms to set collusive prices. On the one hand, preference costs make a deviation from collusion less attractive, as the deviating firm must offer a large enough discount to cover the preference costs. On the other hand, preference costs lock in consumers and make punishment from rivals less effective. When preference costs are low, the latter of the two effects dominates and collusion is more challenging to sustain than in a situation with no preference costs. With high enough preference costs, collusion is a (weakly) dominant strategy. These results do not eventuate in a model with switching costs.