. After reviewing event studies as a method to acquire empirical insights into the competitive effects of mergers, I propose a … market returns of likely competitors to 1,751 of the largest U.S. mergers since 1997. I document that likely competitors …

mergers. The index measures the weighted average reduction in marginal costs required to restore pre-merger equilibrium prices … such as the Hirschmann-Herfindahl Index in the assessment of horizontal mergers. …

conditional probability of eliciting an antitrust challenge (i.e.,remedies and prohibitions) involves the strongest deterrence …

We formulate a simple model of optimal defensive disclosure by a monopolist facinguncertain antitrust enforcement and …

receive fewercustomers so mergers become unprofitable for sufficiently large search costs.This new merger paradox is more …

We study mergers in a market where N firms sell a homogeneous good and consumers search sequentially to discover prices …. The main motivation for such an analysis is that mergers generally affect market prices and thereby, in a search … firms to merge and the welfare implications of mergers. When search costs are relatively small, mergers turn out not to be …

sufficiently large, consumer traffic from the non-merging firms to the merged ones is so small that mergers become unprofitable …