The ongoing fight against tax avoidance in the perspective of the EU legal system: from ATAD I to the proposal for an "Unshell Directive"

The purpose of the thesis is to go deep into the EU anti-tax avoidance legislation's formation process, from ATAD I to the proposal for ATAD III. The first chapter provides an overview of EU tax avoidance situation, highlighting the huge problem of the tax compliance gap, its implications, and the future steps in the EU Agenda to oppose the problem. In the second chapter is presented an historical excursus of EUCJ case law, starting from the concept of abus de droit, passing through the introduction of the first anti-avoidance measures in the directives and ending with an explanation of the main measures introduced by ATAD I and II. This chapter faces up also the concept of shell entity. Then, are identified the main indicators that could be implemented to quantify the number of existent letterbox companies, and the countries in which the phenomenon is more widespread. Furthermore, it is provided an analysis of the red flags that commonly characterized no-substance entities. Lastly, some MNEs' tax schemes are investigated as real examples of aggressive tax planning accomplished with the establishment of shell entities in European Tax Heaven. The third chapter introduces the scope and the contents of Unshell Directive proposal, going deep into substance test’s steps, and sharing experts’ opinions and doubts. Moreover, are analysed the reactions and the possible future impact of ATAD III in Luxembourg and Netherlands. To conclude, are provided some insights and final observations.