This report provides an overview on the economics of attention intermediaries. It addresses the following questions: What are the economics of attention intermediaries? For competition policy, how should markets be defined and market power of attention intermediaries be assessed? What theories...

In many markets, user benefits depend on participation and usage decisions of other users giving rise to network effects. Intermediaries manage these network effects and thus act as platforms that bring users together. This paper reviews key findings from the literature on network effects and...

Competition between two-sided platforms is shaped by the possibility of multihoming. If users on both sides singlehome, each platform provides users on either side exclusive access to its users on the other side. In contrast, if users on one side can multihome, platforms exert monopoly power on...