This book aims to provide tax authorities, policymakers, courts and practitioners with a systematic legal comparison of domestic mandatory disclosure regimes or comparable rules, which are either based on BEPS Action 12/DAC6 or were in force prior to these instruments.

The OECD Action 12 Final Report on mandatory disclosure rules, published in 2015, provides a modular framework for countries to design a disclosure regime to elicit early information relating to aggressive or abusive international tax schemes and the promoters and users of such schemes. The recommendations give countries the flexibility to balance their interest in obtaining information with the compliance costs on taxpayers. The uptake of Action 12 has received significant impetus within the European Union, owing to Council Directive (EU) 2018/822 of 25 May 2018 amending Directive 2011/16/EU regarding mandatory automatic exchange of information in the field of taxation in relation to reportable cross-border arrangements (known as DAC6). DAC6 obligates EU Member States to implement mandatory reporting of cross-border arrangements affecting at least one EU Member State that falls within one of the “hallmarks”. The aim of this book is to provide tax authorities, policymakers, courts and practitioners with a systematic legal comparison of domestic mandatory disclosure regimes or comparable rules, which are either based on BEPS Action 12/DAC6 or were in force prior to these instruments. The comparison also considers issues arising from implementation with respect to legal professional privilege, interaction with other domestic procedural rules and fundamental rights.