Despite the continuing US hospital merger wave, it remains unclear how mergers change, or fail to change, hospital behavior and performance. We open the "black box" of hospital practices through a mega-merger between two for-profit chains. Benchmarking the merger's effects against the acquirer's...

Antitrust authorities search public documents to discover anticompetitive mergers. Thus, investor disclosures may alert them to deals that would otherwise escape scrutiny, creating disincentives for managers to divulge transactions. We study this behavior in publicly traded US companies. First,...

This paper presents estimates of the tax benefits generated by a sample of U.S. mergers and acquisitions involving two public corporations over the period 1968-83 and estimates a "marriage model" based on differences between these mergers and another sample of "pseudomergers" that did not occur...

Most US mergers are not reported to the government on the basis of their size, which can effectively exempt them from antitrust scrutiny, thereby leading to anticompetitive behavior. This paper studies premerger notification exemptions in the US dialysis industry. Over two decades, dialysis...

The success of deregulation in creating a viable private rail freight system in the ?U.S. since 1979 is relatively undisputed. Deregulation has proceeded in three ways: (i) eased rate setting restrictions; (ii) simplified merger applications and approval procedures; and (iii) relaxed route...

We analyze the effect of mergers on various aspects of airline performance during the period 1970-84, using a panel data set constructed by Caves et al. Estimates derived from a simple "matched pairs" statistical model indicate that these mergers were associated with reductions in unit cost. The...

Merger efficiencies provide the primary justification for why mergers of competitors may benefit consumers. Surprisingly, there is little evidence that efficiencies can offset incentives to raise prices following mergers. We estimate the effects of increased concentration and efficiencies on...

We analyze the economic consequences of rising health care prices in the US. Using exposure to price increases caused by horizontal hospital mergers as an instrument, we show that rising prices raise the cost of labor by increasing employer-sponsored health insurance premiums. A 1% increase in...

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...

While the labor market implications of mergers have been historically ignored as "out of market" effects, recent actions by the Department of Justice (DOJ) place buyer market power (i.e., monopsony) at the forefront of antitrust policy. We develop a theory of multi-plant ownership and monopsony...