This paper studies the impact of buyer power on dynamic efficiency. We consider a bargaining model in which buyer power arises endogenously from size and may impact on a supplier's incentives to invest in lower marginal cost. We challenge the view frequently expressed in policy circles that the...

We analyze the efficiency defense in merger control. First, we show that the relationship between exogenous efficiency gains and social welfare can be non-monotone. Second, we consider both endogenous mergers and endogenous efficiencies and find that merger proposals are largely aligned with a...