The Antitrust Analysis of Multi-Sided Platform Businesses

This Chapter provides a survey of the economics literature on multi-sided platforms with particular focus on competition policy issues, including market definition, mergers, monopolization, and coordinated behavior. It provides a survey of the general industrial organization theory of multi-sided platforms and then considers various issues concerning the application of antitrust analysis to multi-sided platform businesses. It shows that it is not possible to know whether standard economic models, often relied on for antitrust analysis, apply to multi-sided platforms without explicitly considering the existence of multiple customer groups with interdependent demand. It summarizes many theoretical and empirical papers that demonstrate that a number of results for single-sided firms, which are the focus of much of the applied antitrust economics literature, do not apply directly to multi-sided platforms.