Joint Dominance and Tacit Collusion: Some Implications for Competition and Regulatory Policy

"The starting point of the present article is the 2004 decision of the Irish communications regulator—ComReg—that Vodafone and O2 enjoyed significant market power (SMP) in the market for mobile access and call

origination within the Republic of Ireland, ie that they were jointly dominant. ComReg agreed that the decision should be annulled following an appeal by a number of mobile operators. The article suggests that the case raises wider issues about the concept of joint (collective) dominance as it has evolved in EU competition law and its applicability in competition and regulatory cases. In particular, the article argues there is no economic basis for the Court of Justice ruling that a uniform test for joint dominance should be applied in both merger and Article 82 cases, and suggests that evidence of coordinated behaviour should be a prerequisite for establishing an infringement of Article 82."