In recent years, states have launched several antitrust investigations targeting digital platforms. A major difficulty involves demonstrating the market power of digital platforms. Market power is defined as the control of the output or the price without the loss of business to competitors. As...

This paper studies regulatory policy interventions aimed at protecting sticky consumers who are exposed to exploitation. We model heterogeneous consumer switching costs alongside asymmetric market shares. This setting encompasses many markets in which established firms are challenged by new...