Opposition Practice At The EPO ' Advice For Patent Owners

• Published date: 02 July 2021
• Subject Matter: Intellectual Property, Patent
• Law Firm: Gill Jennings & Every
• Author: Mr John Fisher and Philippa Makepeace

Opposition proceedings at the EPO provide a time-limited opportunity for a third party to challenge the validity of a granted European patent centrally, with the aim of achieving revocation, or at least a limitation, of the granted patent rights. In this article, we will give an overview of the opposition procedure, before delving into tips and strategies for patent proprietors when faced with opposition proceedings.

Overview of the EPO opposition procedure

EPO opposition proceedings are a very cost-effective tool for third parties who wish to oppose the grant of a European patent. A granted European patent is converted into a bundle of independent national patent rights that are administered at the national level under the patent laws of each country. EPO opposition proceedings are an exception to this, whereby the grant of a European patent can be contested centrally for a limited period of time after the date of grant.

The cost of challenging the grant of a European patent centrally at the EPO is a small fraction of the cost of pursuing separate invalidity proceedings in the national courts in each country where the patent is in force. Furthermore, any decision by the EPO to revoke or limit a European patent is not open to challenge in the national courts. As around two-thirds of oppositions result in limitation or revocation of the opposed patent, EPO opposition proceedings are both a powerful tool for the opponent and a serious threat for the patent owner.

Since 2016 the European Patent Office has applied a streamlined opposition procedure that aims to deliver a first-instance decision within two years from the date of grant for straightforward cases. Procedural economy is an important characteristic of these...