The central objective of this work is to study (international) lis pendens, as Brazilian civil procedural law makes it impossible for lawsuits in different jurisdictions to lead to a stay. In the meantime, the central problem lies precisely in the position adopted by Brazilian processualist doctrine, which is the same, even when international treaties establishing lis pendens exist for actions brought in different countries, such as MERCOSUR, for the protocols relating to contracts and arbitration awards or awards. The study therefore passes on the definitions of lis pendens in Brazilian law, as well as the Mercosulino protocols on the subject, raising the question about the compatibility between domestic law and international treaties. This turns on the issue of reconciling domestic and international groupings by one-tier and dualist theories, in an attempt not only to clarify the Brazilian position, but also to provide a solution to the problem raised in the light of international law.