EPO Oppositions: Moving Faster In Future

The "Opposition" procedure is a widely used and cost-effective way to challenge a patent granted by the European Patent Office (EPO). Within nine months of the grant of a European Patent, third parties can lodge oppositions against the patent. A significant proportion of European Patents are opposed – some survive the opposition process unscathed while others are revoked or are maintained but with narrower scope.

The most common criticism of the opposition process, however, is that it is slow, with lengthy gaps between the various stages of the procedure. Most oppositions take 3-4 years or more to progress to a decision, and because many decisions are appealed it may be another 2-3 years or more after that before a final outcome is reached.