When filing an international application claiming priority from an earlier national, European or international application already searched by the EPO (i.e. a "doublure"; see GL/PCT‑EPO B‑IV, 1.1), the applicant may submit to any receiving Office informal comments aimed at reacting to the objections raised in the search opinion established by the EPO for the priority application. At the EPO, this service is called "PCT Direct".
Such informal comments are to be understood as arguments regarding the patentability of the claims of the international application and also possibly as explanations regarding any modifications to the application documents, in particular to the claims, in comparison with the priority application. If the requirements under GL/PCT‑EPO A‑IV, 1.2, are met, the informal comments will be taken into account by the EPO as ISA when it establishes the international search report and written opinion for the international application.
For the processing of applications under the PCT Direct service by the EPO as ISA, see GL/PCT‑EPO B‑IV, 1.2.