Worldwide, the overwhelming majority of large horizontal mergers are cleared by antitrust authorities unconditionally. The presumption seems to be that efficiencies from these mergers are sizeable. We calculate the compensating efficiencies that would prevent a merger from harming consumers for...

This paper introduces the Werden-Froeb Index (WFI) to assist in evaluating merger-specific efficiencies in horizontal mergers. The index measures the weighted average reduction in marginal costs required to restore pre-merger equilibrium prices and quantities after the (full or partial) merger...

We study horizontal mergers on two-sided markets between horizontally differentiated platforms. We provide a theoretical analysis of the merger's price effect based on the amount of cost savings it generates, the behavior of outsider platforms, and the size of cross-group network effects. We...