The staff at an antitrust agency can focus on either coordinated interaction (collusion) or unilateral effects theories when investigating a proposed merger. This paper statistically models whether the choice of economic theory materially affects the Federal Trade Commission's (FTC) enforcement...

Most mergers filed at the enforcement agencies are conglomerate in nature with only minor horizontal overlaps. An enforcement agency may challenge the merger, if any overlap is believed to be adversely affected by the transaction. While the merging firm is entitled to a hearing in federal court,...

Most mergers involve multiple markets. The potential for settlement can vary by the fraction of the overall deal attributable to the markets of concern. (i.e., by the “overlap”). If an antitrust agency challenges a merger having only a small overlap, negotiating a settlement is very likely;...

In this study, merger enforcement at the Federal Trade Commission is shown to be affected by structural variables (the Herfindahl, the change in the Herfindahl, and the number of significant rivals), an entry index, and three evidence variables (hot documents, validated customer complaints, and...

Physicians' practices vary widely, as do their effectiveness and reimbursement. Using a merger of six orthopaedic groups in southeastern Pennsylvania, we find that such groups can generate large, anti-competitive price increases without any demonstrated increases in quality (indirectly measured...

The vertical merger of AT&T and Time Warner combined one of the largest downstream multiple video program distributors (MVPDs) with one of the largest upstream providers of pay-TV programming. The U.S. Department of Justice sued to block the merger, arguing that the combined entity would have...