The earliest U.S. antitrust laws were adopted after technological changes — most importantly, the development of a national railway network — made the U.S. political union a single economic market. They were adopted with the stated, and no doubt largely sincere, purposes of preventing...

We discuss strategic ways that sellers can use tying and bundling with requirement conditions to extract consumer surplus. We analyze different types of tying and bundling creating (i) intra-product price discrimination; (ii) intra-consumer price discrimination; and (iii) inter-product price...

Vertical restraints have been subject of lively policy and academic discussions. Scholars associated with the Chicago School challenged early foreclosure doctrines by arguing that vertical restraints primarily reflected efficiency considerations. More recently, industrial organization economists...

This is a survey of the economic principles that underlie antitrust law and how those principles relate to competition policy. We address four core subject areas: market power, collusion, mergers between competitors, and monopolization. In each area, we select the most relevant portions of...

I discuss the impact of tying, bundling, and loyalty/requirement rebates on consumer surplus in the affected markets. I show that the Chicago School Theory of a single monopoly surplus that justifies tying, bundling, and loyalty/requirement rebates on the basis of efficiency typically fails....

We examine the intersection of patents and antitrust where a patent holder uses the monopoly power it possesses in the market for a patented product to exclude competitors in an adjacent market and attempt to monopolize or monopolize the adjacent market. The present scheme for awarding patents...

This paper asks how much the strength of network effects depends on the stability and structure of the underlying social network. I answer this using extensive micro-data on all potential adopters of a firm's internal video-messaging system and their subsequent video-messaging. This firm's New...

Antimonopoly laws must contain effective provisions for the attack of exclusionary behavior by firms with market power while at the same time not attacking procompetitive behavior by entrants or incumbents. This paper suggests seven textual criteria by which a new law may be evaluated in its...