The patent proprietor may defend the patent in different versions on the basis of a main request and one or more auxiliary requests. An auxiliary request is considered only under the condition that the main request or a higher ranking auxiliary request is found not to meet the requirements of the European Patent Convention. The submission of new requests is procedurally limited. Requests submitted in oral proceedings are, as a rule, not admitted unless they can be readily discussed by the panel and the opponent, or if they are a reaction to a new objection made in the oral proceedings. This means, as a rule, that primarily only small, particularly editorial amendments may be made during oral proceedings.
At the end of the oral proceedings, which typically take one sometimes two days, the Opposition Division deliberates and issues its decision, i.e. either a full revocation of the patent, a limitation, or the maintenance of the patent as granted. Due to the COVID-19 pandemic, oral proceedings only take place in the form of video conferences, at least until September 19, 2021.
Every year, oppositions are filed against about 4.000 patents which corresponds to about 4 % of all granted patents. From the official statistics of the European Patent Office, it appears that over the years roughly equal numbers of the opposed patents are fully revoked, maintained in amended form and maintained as granted, however with an increasing tendency of negative results.