Antitrust Criminal Penalties Enforcement and Reform Act of 2004 Extension Act of 2010 - Amends the Antitrust Criminal Penalty Enhancement and Reform Act of 2004 to make permanent provisions of that Act limiting civil damages in antitrust enforcement actions involving conduct covered by antitrust leniency agreements.
Directs the Comptroller General to submit a report to the congressional Judiciary Committees on the effectiveness of the Antitrust Criminal Penalties Enforcement and Reform Act of 2004, both in criminal investigation and enforcement by the Department of Justice (DOJ) and in private civil actions.