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...

Each stage of merger analysis involves predictions about uncertain events. The quality of merger enforcement and its ability to improve consumer welfare depend heavily on how well the federal antitrust agencies cope with such uncertainty. The agencies and the courts have to date adopted an...