On March 9, 2009, the Antitrust Division of the Department of Justice (“DOJ”) announced that it had brought suit against Election Systems & Software, Inc. (“ES&S”) to challenge its acquisition in September of 2009 of Premier Election Solutions Inc. (“Premier”) from Diebold, Inc. At the same time, the DOJ filed a settlement agreement with ES&S that requires the divestiture of the assets of Premier in order to restore competition in the market for voting equipment systems in the United States. There are several lessons from this enforcement action that apply to companies in other markets.