(31)In the context of widespread infringements or widespread infringements with a Union dimension, the rights of defence of the traders should be respected. This requires, in particular, giving the trader the rights to be heard and to use, during the proceedings, the official language or one of the official languages used for official purposes in the Member State in which the trader is established or resides. It is also essential to ensure compliance with Union law on the protection of undisclosed know-how and business information.