This paper considers the effect of taxes on the definition of relevant markets in antitrust analysis by examining various measures used within the hypothetical monopoly test. We show that the use of net margins (between producer prices and marginal cost) is a proper correction, but that it is...

Waste management has gradually become an issue of major economic importance. Many operators have developed economic activities, creating, in so doing, a host of markets. The application of competition law on such markets will be assessed in this contribution, regarding more especially the...

The determination of market power of a firm or a group of firms and the prevention of its negative effect on the other market participants requires a previous definition of the relevant market. The relevant market represents a group of products or geographical areas that render it impossible for...

The recently issued revision of the U.S. Horizontal Merger Guidelines, like its predecessors and mirrored by similar guidelines throughout the world, devotes substantial attention to the market definition process and the implications of market shares in the market that is selected. Nevertheless,...

In this short and mainly expository article, we explain the “hypothetical monopolist test” that has become the standard methodology for identifying relevant antitrust markets in merger cases, and discuss two approaches to implementing the test. We then focus on the implementation of the test...