Executive summaryThe Polish Tax Code was supplemented with regulations imposing an obligation to report tax arrangements – the mandatory disclosure rules (MDR) regulations on 1 January 2019.The Polish MDR regulations implement the European Union (EU) Directive 2018/822 of 25 May 2018 on the mandatory disclosure and automatic exchange of cross-border tax arrangements (the Directive or DAC6) and also impose further reporting requirements.As the Polish legislation goes beyond the minimum standard set forth in the Directive, two types of tax arrangements are recognized under the Polish Tax Code: (i) the so-called “cross-border tax arrangements” (consistent with the EU Directive); and (ii) other tax arrangements (which are...