Over the years, the UCTD has become one of the core EU directives aiming at the protection of both businesses and consumers (B2C), i.e., at the achievement of the appropriate balance between the parties’ rights and obligations. However, the UCTD has also left quite a number of important legal questions unanswered. Besides the general clauses on the assessment of the unfairness of contractual terms, there remains a high degree of uncertainty as to the meaning of the transparency requirement and the legal consequences of unfair contractual terms. As a result, in spite of CJEU settled case law, as well as European Commission interpretation guidelines, there are diverging patterns in the national case law of the Member States. The aim of this paper is to investigate these diverging patterns by looking more closely into national case law and into the relationship between the CJEU and the Member States courts, taking as a case study the way in which the UCTD was applied in five countries (Austria, Croatia, France, Italy and Poland) in cases involving consumer loans indexed to the Swiss franc. The survey shows that there are noticeable differences in the interpretation of core concepts underlying the UCTD, such as the unfairness test, the exclusions from the unfairness assessment, and the transparency requirement. The most problematic areas, however, concern the legal consequences of the unfairness of contractual terms. By relying on the analysis of these and related issues, the authors have come to the conclusion that even after 30 years of the existence of the UCTD, there are still many important legal questions that need solving.
