Mergers have the potential for negative social welfare consequences from increased likelihood or effectiveness of future collusion. This raises the question of whether there are meaningful thresholds for the post-merger industry that should trigger significant scrutiny by the Department of...

We provide empirical evidence that many multi-product firms have each participated in several cartels over the past 50 years. Standard analysis of cartel conduct, as well as enforcement policy, is rooted in the presumption that each cartel in which a given firm participates is a singular...