This article studies the design of optimal mechanisms to regulate entry in natural oligopoly markets, assuming the regulator is unable to control the behaviour of firms once they are in the market. We adapt the Clark-Groves mechanism, characterize the optimal mechanism that maximizes the...

This Article advances a novel theoretical model for assessing policy interventions against Facebook. As prosecutors barrel forward against digital platforms, soon it will fall upon courts and, eventually, regulators to devise remedies. We argue that any sensible solution must include...