Here's what the abstract states:
Merger regulation affects large transactions in the market for corporate control in both the European Union (EU) and the United States (US). This paper compares the merger enforcement policies of the two regions using descriptions of the merger investigations prepared by the staff of the EU and the Federal Trade Commission. The policies are found to share a common foundation with substantial weight being placed on both the market structure characteristics and the likelihood of effective entry. US enforcement was broader-based in that it scrutinized markets that might be characterized as raising oligopoly, unilateral, and dominant firm concerns, while the EU policy focused largely on market dominance. Neither regime is found to be stricter in all circumstances, since the market and firm characteristics impact the enforcement decisions differently. However, we find that the US regime is more predictable (given our measures of the explanatory variables), tougher on strong dominance cases and oligopoly cases, but more permissive on weak dominance cases.
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