The Commission increases or decreases the fine in respect of the conduct of each undertaking. The Guidelines  set out a list of aggravating circumstances resulting in an increase in the amount of the fine.

One of the most common aggravating circumstances is the repeated infringement. This means that there has been a previous ruling against the undertaking although it may not have necessarily given rise to a sanction. The first decision does not have to be final. The fact that the two infringements are contemporaneous is of no relevance to the sanction where the undertaking continued to participate in the second even though it had been found guilty of the first. The provisions to which the sanctions relate can be merely similar and the practices do not have to have been implemented on the same market, concern the same products or be adopted by the same entity

The offense of repeated infringement is limited in time: a lapse of 15 years between two infringements excludes an increase for repeated infringement.

Aggravating circumstances include:

– refusing to cooperate or obstructing the course of the investigation,

– hiding evidence,

– continuing the anticompetitive behavior despite having given  assurances to the Commission,

– the adoption of retaliatory measures,

– the role of  leader or instigator and coordinator played by one or several undertakings.