We document the effects of a comprehensive set of US retail mergers. On average, prices increase by 1.5% and quantities decrease by 2.3%, with significant heterogeneity in outcomes across mergers. Price changes correlate with the screens codified in the Horizontal Merger Guidelines. Through a...

We hand-collect and standardize information describing all 3,055 antitrust lawsuits brought by the Department of Justice (DOJ) between 1971 and 2018. Using restricted establishment-level microdata from the U.S. Census, we compare the economic outcomes of a non-tradable industry in states...

Antitrust enforcement in the United States has declined since the 1960s. Building on several new datasets, we argue that this decline did not reflect a popular demand for weaker enforcement or any other kind of democratic sanction. The decline was engineered by unelected regulators and judges...

This survey examines recent developments in economic research relating to antitrust, paying specific attention to research in the areas of collusion and merger enforcement. Research relating to both collusion and mergers has made significant advances in the last twenty years. With respect to...

Economic analysis of competition regulation is most developed in the domain of horizontal mergers, and modern agency guidelines reflect a substantial consensus on the appropriate template for merger assessment. Nevertheless, official protocols are understood to rest on a problematic market...

The federal government stands poised to exercise its constitutional right to regulate financial markets, an area traditionally left to competing provincial securities commissions. The current state of securities regulation renders impotent US-style takeover defences, such as poison pills and...

The challenge of effective merger enforcement is tremendous. U.S. antitrust agencies must, by statute, quickly forecast the competitive effects of mergers that occur in virtually every sector of the economy to determine if mergers can proceed. Surprisingly, given the complexity of the regulators...

In this article, I explain the inadequacy of our current state of knowledge regarding the effectiveness of antitrust policy towards mergers. I then discuss the types of data that one must collect in order to be able to perform an analysis of the effectiveness of antitrust policy. There are two...

We analyze the optimal dynamic policy of an antitrust authority towards horizontal mergers when merger proposals are endogenous and occur over time. Approving a currently proposed merger will affect the profitability and welfare effects of potential future mergers, the characteristics of which...

In this paper we propose a method to evaluate the effectiveness of U.S. horizontal merger policy and apply it to the study of five recent consumer product mergers. We selected the mergers from those that, from the public record, seemed to be most problematic for the antitrust agencies. Thus we...