Jonathan Baker (American University) has posted Market Concentration in the Antitrust Analysis of Horizontal Mergers to SSRN. Baker’s article is another of the entries which will be appearing in the forthcoming Antitrust Law and Economics volume edited by Keith Hylton (Elgar Publishing) (see this post for links to others). Here is the abstract:
This handbook chapter will appear in Antitrust Law & Economics (Keith Hylton, ed. forthcoming 2009). It describes the role of market concentration in the legal framework for the antitrust review of horizontal mergers and evaluates the extent to which modern economic analysis supports a role for concentration in that review. The chapter examines market definition, the predicate for measuring market shares and market concentration, and the role of market shares and concentration in the analysis of the coordinated and unilateral competitive effects of merger. The central issue considered is when and how market shares, and market concentration statistics derived from them, form an appropriate basis for presuming harm to competition from merger.
Check it out, as well as this thoughtful review of Baker’s article in the Antitrust Source from John Woodbury.