Terms of a provision of EU law which makes no express reference to the law of the Member States must be given an autonomous and uniform interpretation throughout the European Union, taking into account the context of the provision and the purpose of the legislation in question.
"25. In order to ascertain whether a national body, such as BKK, which is governed by public law and which is tasked with the management of a statutory health insurance fund, must be considered a ‘business’ within the meaning of the Unfair Commercial Practices Directive and whether it is, in that capacity, subject to the requirements laid down by that directive in the event that, as in the present case, it provides misleading information to its members, it should be noted from the outset that, according to the Court’s settled case-law, the need for uniform application of EU law and the principle of equality require that the terms of a provision of EU law which makes no express reference to the law of the Member States for the purpose of determining its meaning and scope must normally be given an autonomous and uniform interpretation throughout the European Union; that interpretation must take into account the context of the provision and the purpose of the legislation in question."
Public body entrusted with a task of general interest, such as management of compulsory health insurance is a “trader” within the meaning of the Unfair Commercial Practices Directive.
"35. That objective of the Unfair Commercial Practices Directive, which is to fully protect consumers against practices of that kind, relies on the assumption that, in relation to a trader, the consumer is in a weaker position, in that the consumer must be considered to be economically weaker and less experienced in legal matters than the other party to the contract (see, by analogy, Shearson Lehman Hutton, paragraph 18).
36. Accordingly the Court has already held that, for the purposes of the interpretation of that directive, the concept of consumer is of the utmost importance and that the provisions of that directive are essentially designed with the consumer as the target and victim of unfair commercial practices in mind
37.In a situation such as that at issue in the main proceedings, BKK’s members, who must manifestly be regarded as consumers within the meaning of the Unfair Commercial Practices Directive, could be deceived by the misleading information circulated by that body thus preventing them from making an informed choice (see recital 14 in the preamble to that directive) and leading them to take a decision they would not have taken in the absence of such information, as envisaged by Article 6(1) of that directive. In those circumstances, whether the body at issue or the specific task it pursues are public or private is irrelevant.
38. In view of the above, a body such as BKK must be considered a ‘trader’ within the meaning of that directive."
C-59/12 - ECLI:EU:C:2013:634