Article by
Christine Wilson 
,
Tim Muris 
,
Benjamin Labow and
Bilal Sayyed
On April 20, 2010, the US Federal Trade Commission
("FTC") released proposed revisions1 to the
Horizontal Merger Guidelines2 ("Guidelines").
Developed jointly with the Department of Justice, the proposed
Guidelines incorporate a number of noteworthy revisions: the
Guidelines significantly raise the concentration thresholds at
which mergers are considered to warrant greater scrutiny; they
deemphasize the role of market definition; and they place greater
reliance on economic models in mergers involving differentiated
products.
Background
On September 22, 2009, FTC Chairman Jon Leibowitz and Assistant
Attorney General Christine Varney announced3 that the
antitrust agencies would hold public workshops to consider
revisions to the 1992 Horizontal Merger Guidelines.4
With "the bulk of the [Horizontal Merger] Guidelines ... well
over seventeen years old," Chairman Leibowitz indicated
