1. A competent authority may decline to take part in a coordinated action for any of the following reasons:

(a) in respect of the same trader, a criminal investigation or judicial proceedings have already been initiated, a judgement has been given, or a court settlement has been reached, concerning the same infringement in that competent authority's Member State;

(b) the exercise of the necessary enforcement powers has already been initiated before the issuing of an alert referred to in Article 17(3), or an administrative decision has been adopted against the same trader in respect of the same infringement in that competent authority's Member State in order to bring about the swift and effective cessation or prohibition of the widespread infringement or widespread infringement with a Union dimension;

(c) following an appropriate investigation, it is apparent that the actual or potential impact of the alleged widespread infringement or widespread infringement with a Union dimension in that competent authority's Member State is negligible and therefore no enforcement measures need to be adopted by that competent authority;