During recent years, the OECD has carried out continuous work regarding the development of the rules that make up Pillar Two, that is, the Income Inclusion Rule (IIR) and the Under taxed Payments Rule (UTPR). Along these same lines, the European Union has followed the same steps and has developed the normative introduction of the same rules. Now, with respect to the Subject to Tax Rule (STTR), because it is applicable through a bilateral tax treaty, its inclusion at the European regulatory level is not so direct; however, there are regulatory proposals capable of providing a tax response similar to that sought by the STTR of the OECD Pillar Two. An example of this is the Proposal for a Council Directive on a common system of taxation applicable to interest and royalty payments made between associated companies of different Member States.