Property rights have long been associated with a simple and distinctive technology: exclusion. But technologies can become outdated as conditions change, and exclusion is no exception. Recent decades have featured profound changes that have made exclusion a less useful, less necessary, and more...

Scholars and courts have long debated whether and when "parallel pricing" — adoption of the same price by every firm in a market — should be considered a violation of antitrust law. But there has been a comparative neglect of the importance of "parallel exclusion" — conduct, engaged in by...

We consider a software vendor first selling a monopoly platform and then an application running on this platform. He may face competition by an entrant in the applications market. The platform monopolist can benefit from competition for three reasons. First, his profits from the platform...

Access to a platform's services often requires consumers to use a complementary hardware product or service, e.g., Internet service is needed to access the YouTube platform. Typically, such access products are provided by third-party firms. More recently, however, some major platforms like...

There is vigorous debate over the ability of the current antitrust enforcement regime in the United States to protect against potential reductions in competition caused by large technology companies. Some commentators have argued that current antitrust rules and processes cannot address...

Platforms often use fee discrimination within their marketplace (e.g., Amazon, eBay, and Uber specify a variety of merchant fees). To better understand the impact of marketplace fee discrimination, we develop a model that allows us to determine equilibrium fee and category decisions that depend...