BEPS Action 6 established a “minimum international standard” to fight against tax treaty shopping, in particular by proposing to add article 29(9) of the OECD Model (2017) (the so-called principal purpose test, PPT) to tax treaties. This article explains why the PPT is susceptible to be interpreted differently across the world and, especially, shows that this outcome is very likely to materialize in view of some administrative and judicial decisions in different countries in 2021 in very relevant tax treaty shopping cases. Further tensions are added by the recent proposal for a directive by the European Commission against the use of shell companies since it is not in line with the BEPS Action 6 minimum standard. In essence, it is argued that the BEPS Action 6 minimum standard needs to be complemented with some further actions if the goal is to have a real and homogeneous anti-tax treaty shopping international standard and more legal certainty.