Multisided platforms are ubiquitous in today's economy. Although newspapers demonstrate that the platform business model is scarcely new, recent economic analysis has explored more deeply the manner of its operation. Drawing upon these insights, we conclude that enforcers and courts should use a...

We explore the implications of the widely accepted understanding that competition law is common — or “judge-made” — law. Specifically, we ask how the rule of reason in antitrust law should be shaped and implemented, not just to guide correct application of existing law to the facts of a...

The distinction between complements, substitutes, and independent goods is important in many contexts. It is well known that when consumers' conditional indirect utilities for two goods are superadditive, the goods are gross complements. Generalizing insights in Gans and King (2006) and Gentzkow...

An unusual feature of two-sided markets is that there is no consensus regarding what they are. Our approach to deriving a definition is to identify examples that have been found to represent an interesting phenomenon in common and then reverse engineer the outcomes to determine the drivers of...

In this paper we analyze taxation using the conjectural variations model of oligopoly. We demonstrate the way in which the incidence of a tax depends upon the pattern of firm interaction. The results obtained have important implications for the controversy surrounding the question of whether a...

This is a response to a request for comments issued by the Department of Justice and Federal Trade Commission to revise their Horizontal Merger Guidelines. Our comments highlight three areas for which new guidance or clarification of existing guidance is appropriate: market definition,...

We examine the effects of merger and merger policy on a potential entrant’s pre-merger investment incentives. We establish conditions under which the possibility of merger can induce an entrant to inefficiently imitate an incumbent’s product instead of innovating with a more differentiated...