EPO opposition and appeal proceedings

You may be familiar with the European Patent Office (EPO) and its role in examining patent applications and granting patents, but did you know that there is also a system available for you to try to invalidate granted European patents? This article describes this system and how you can use it to restrict, or even get rid of, European patents which may impact on your commercial activities.

European patent applications are examined thoroughly, and patents granted by the EPO are widely regarded as being robust. However, patent examiners are not infallible and nor are they able to spend unlimited time searching for potentially relevant prior disclosures or examining each application. Accordingly, although granted European patents are presumed to be valid, they are not guaranteed to be so. The European Patent Convention (EPC) recognises this by including an Opposition procedure which allows you to challenge the grant of a European patent in respect of all of the countries for which the patent is effective. This is a significant advantage compared to the alternative of filing individual revocation proceedings before National Courts.     

The procedure has defined rules. An opposition must be filed within a strict 9-month period following the grant of the European patent. As an opponent, you must file a statement setting out clearly why you think that the European patent should not have been granted and pay a fee (currently €880). Oppositions are limited to three main grounds:

• That the European patent lacks novelty and/or is obvious
• That the European patent does not disclose the invention in way which is sufficiently clear and complete
• That the European patent contains subject-matter which was not in the original application

Most often, opponents will identify prior art documents which have not been referred to during the examination of the application and which call into question the novelty or inventiveness of the granted claims. Documents which were discussed during examination can also be used if for example it can be shown that the examiner misinterpreted the disclosure. It is also possible to argue that the granted claims lack novelty by providing evidence of public prior use of the invention, e.g., by way of commercial sales.

Once an opposition has been filed, and the 9-month period has expired, the Patentee is given the opportunity to respond. The Patentee will inevitably try to rebut any objections and often will also file one more limited versions of the granted claims as ‘auxiliary requests’. Opponents may then file further comments and arguments.

The Opposition procedure is primarily a written procedure however most oppositions are finally decided during an oral hearing. The Patentee, opponents and a three-member panel of EPO examiners convene to discuss all of the objections raised. At the end of the hearing, the panel chairperson announces a decision. There are three possible outcomes: the European patent may be revoked, meaning that the patent is deemed never to have been granted; the opposition may be rejected, meaning that the patent is maintained in its granted form, or the patent may be maintained in amended form on the basis of one of the ‘auxiliary requests’. Over the last 10 years or so, the proportion for each outcome is around 33%:26%:41% respectively. There is some variation with technical field, but the most likely outcome is for patents to survive opposition in an amended form.

Prior to the COVID-19 pandemic, oral hearings took place at the premises of the EPO, either in Munich or The Hague. Travel restrictions however led to the use of video-conferencing, initially as a temporary measure, but now adopted by the EPO as the default for opposition hearings. Parties and their representatives now no longer have to arrange travel and accommodation, saving both time and cost.    

A written decision detailing all of the arguments made by the parties, and the reasoning used by the EPO panel, is typically sent to the parties within a few months of the hearing. In recent years, the EPO have made efforts to speed up the processing of oppositions and the provision of the written decision. The target is to complete the whole procedure within 18 months from the filing of an opposition, but durations of 2-3 years are not uncommon. Often however, this does not mark the end of the story.

Decisions taken in opposition proceedings are subject to appeal. Any party who is adversely affected by the decision has the right to file an appeal to the EPO’s Board of Appeal. So, if the patent is revoked, the patentee may appeal and if the opposition is rejected, the opponent may appeal. And if the patent is maintained in an amended form, both the patentee and the opponent may appeal as both were adversely affected by the decision.

There is a strict deadline of two months, starting from the date of the written decision to file a notice of appeal and pay an appeal fee (currently €2,925). A full statement, setting out the grounds of appeal is then due within a further two months. Once filed, the Board of Appeal will consider the case and make a decision. As with the opposition procedure, most appeals conclude with an oral hearing where the parties make their cases before a three-member panel. Officially, the Boards of Appeal have not adopted video-conferencing as the default for oral hearings and so parties may still have to travel to Munich to attend. In practice however, most Boards are open to conducting hearings virtually, particularly if all parties agree.

An appeal is strictly a legal process. Its purpose is to review the decision reached in the opposition proceedings in order to decide whether it was correct or not. Importantly, an appeal is not an opportunity for the parties to re-litigate issues from first principles. There are strict rules concerning the introduction of new documents or evidence, new lines of argument and new auxiliary requests. Parties must be prepared for Boards of Appeal to simply dismiss or ignore new evidence or submissions, particularly if these relate to matters which could and should have been raised during the opposition proceedings.  

At the end of the oral hearing, the chairperson of the Board of Appeal will announce a decision. This decision is final. There are circumstances where the case may be sent back to the opposition stage to consider a particular matter but should the Board of Appeal rule the patent to be maintained or revoked, then the proceedings are at an end.

There is a backlog of cases before the Boards of Appeal, partly due to fewer cases being decided during the pandemic. Good progress has been made in addressing this though and the current objective is to for 90% of cases to be less than 24 months old by the end of 2025.

The EPO’s opposition procedure is a relatively simple and cost-effective way for you to try to remove, or restrict the scope of, a granted European patent, particularly when compared to individual national revocation proceedings. The procedure is perhaps not as quick as may be desirable, especially when factoring in an appeal, but it can be a valuable tool to build into you IP strategy. Don’t forget however that just as you can oppose your competitor’s European patents, your competitors can oppose yours!

Our attorneys here at Mathisen & Macara have extensive experience of EPO opposition and appeal proceedings, including acting as advocates for our clients at the crucial oral hearing stages. We would be delighted to advise you should you wish to oppose a European patent or if you receive an opposition to one or your own patents.