Digital platforms have reshaped many product markets and play an increasingly important role in economies around the globe. Some of these platforms have become powerful players and may possess a lot of market power. Economists use a number of indicators to assess market power. In this article we...

The article addresses the role market definition can play for EU competition practice in the platform economy. The focus is on intermediaries that bring together two (or more) groups of users whose decisions are interdependent and which therefore are commonly referred to as “two-sided...

For many products, platforms enable sellers to transact with buyers. We show that the competitive conditions among sellers shape the market structure in platform industries. If product market competition is tough, sellers avoid competitors by joining different platforms. This allows platforms to...