On 22 September 2009, the US Department of Justice and the Federal Trade Commission announced plans to solicit public comment and host joint workshops to explore the possibility of updating the Horizontal Merger Guidelines. The Guidelines date from 1992, and while they have been regarded as very successful, they have also been criticized increasingly as out of date.

This review was thus widely anticipated; indeed, the Antitrust Modernization Commission recommended that the agencies revisit the Guidelines. At the same time, this may represent one of the most important policy initiatives announced so far in the new Obama Administration.

In this article, published in the Fall 2009 edition of Antitrust, a panel of antitrust experts share their perspectives on what we can expect from this excercise.