The US non-profit organization American Free Enterprise Chamber of Commerce (AFECC) has lodged with the Belgian Constitutional Court a claim for the annulment of the Undertaxed Profits Rule (UTPR). Belgium adopted the UTPR as part of the implementation of the EU Global Minimum Tax Directive, which in turn implements throughout the EU the OECD/IF Pillar Two framework with variations imposed by the EU institutional architecture. The grounds for the claim have not been made public, but there is an ongoing debate within the international tax community on the compatibility between the UTPR and tax treaties. The claim was received by...