Since 1996, the European Commission has been operating a leniency programme, under which companies cooperating with its cartel investigations can obtain immunity from fines or a reduction of fines. Leniency plays a prominent role in EU cartel enforcement today. This paper assesses the positive...

This paper discusses the theory and practice of leniency in antitrust enforcement, i.e. the granting of immunity from penalties or the reduction of penalties for antitrust violations in exchange for cooperation with the antitrust enforcement authorities. After a description of the practice of...