The paper reflects the results of the research on the relation between tax avoidance regulation and sovereignty, in particular within European Union, analyzing the effective regulatory methods for limiting/eliminating aggressive tax planning by the multinational companies. The good practice in fiscal regulation and the results generated by the tax jurisprudence have led to common, yet flexible, solutions for the actual fight against companies’ abusive fiscal conduct, when taking advantage of the tax competition.

The topic of the research is significant in the actual context, as the integration of national economies and markets has increased substantially, both within EU and globally. This has put a strain on the domestic tax rules, which have to be inter-connected and in line with the demands of the international taxation requirements.

Presently, the EU member states’ fiscal sovereignty blocks the option for common regulation in this field and the paper points out how the efficient patterns used in the international taxation significantly impact on the traditional concept of sovereignty, changing its features not in a formal, but in informal sense.