Two-Sided Market Definition

This paper addresses the analysis of market definition when the parties involved in an antitrust or merger analysis include one or more two-sided platforms. We discuss how standard market definition measures such as SSNIP tests, diversion ratios, and conditional logit demand analyses have to be modified to account for the unique characteristics of two-sided platforms. We also review how market definition of two- sided platforms was treated in recent US and EC case law.