In Europe, patents can be challenged after they are granted in opposition proceedings before the European Patent Office (EPO). Opposition proceedings allow the validity of newly-granted patents to be challenged on certain limited grounds, while allowing the challenger to remain anonymous. This provides an offensive tool that can be used to remove potential blocking patents at a much lower cost and lower risk than litigation. 

Renner Otto's attorneys are experienced in both attacking and defending patents in opposition proceedings at the EPO. We understand the considerations that go into the grounds for opposing patents, in finding and applying prior art, and in considering patent invalidity based on amendments to the claims made during prosecution at the EPO.  Our attorneys are also well-versed in opposing such grounds for opposition, including the considerations involved in possible claim amendments that can be suggested as fallback positions that still provide useful patent protection.  We work with European counsel to navigate through all phases of the complex opposition process, from the filing of grounds for opposition and other written submissions, to oral hearings before the Opposition Division and possible appeals.  

Beyond the opposition proceedings themselves, our attorneys' experience in this area also has the benefit of informing our approach to patent prosecution before the EPO.  Through careful attention to how the claims are amended during prosecution, we seek to minimize the grounds upon which an opposition might be based in the first place.