Obtaining a European patent: the opposition procedure

The opposition procedure, which does not exist for a French patent before the INPI, has many advantages, in terms of cost, effects and, to a certain extent, speed. As for the patentee, if he obtains rejection of the opposition, his title is strengthened all the more.

Once granted, a European patent can be contested through a specific procedure known as opposition. This is an administrative procedure which enables the validity of a European patent to be contested directly before the European Patent Office (EPO), with the aim of obtaining its revocation or limiting its scope. Opposition may be lodged by any person (except the patentee himself), but is only open for a period of nine months from publication of the mention of grant of the European patent in the European Patent Bulletin.

The purpose of this information sheet is to explain the conditions under which an objection can be lodged, the procedure and its effects.