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,...

The "parallel behavior is enough" standard cannot assist the courts in distinguishing horizontal agreements to restrain trade from normal competition. It would very likely impose significant costs on the economy by distorting competitive incentives and encouraging meritless litigation designed...

We analyze the central economic issues raised by U.S. v Microsoft. Network effects and economies of scale in applications programs created a barrier to entry for new operating system competitors, which the combination of Netscape Navigator and the Java programming language potentially could have...