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...

The web economy has grown rapidly in the last decade. Online businesses have several key features that are important for understanding the pro-competitive and anti-competitive strategies they may engage in. The two-sided markets literature helps elucidate many of these strategies. It also...

Platform businesses that facilitate connections between different stakeholders play an increasingly prominent role in the economy. In 2018, the U.S. Supreme Court issued a seminal decision, Ohio et. al. v. American Express, on the analysis of antitrust issues involving these sorts of businesses....

The SSNIP test and Critical Loss Analysis are widely used tools for determining market definition in merger and sometimes other antitrust matters. However, the standard techniques used to test for a relevant antitrust market are incorrect when the firms in question operate two-sided platforms....

Two-sided platforms (2SPs) cater to two or more distinct groups of customers, facilitating value-creating interactions between them. The village market and the village matchmaker were 2SPs; eBay and Match.com are more recent examples. Other examples include payment card systems, magazines,...