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Oppositions can be filed within nine months of a European patent being granted by the EPO. Thousands of European patents are challenged each year. Why…

Successful – 35% of European patents challenged are revoked and 34% amended i.e. a ‘wounding’ rate of ~ 70%

Quick – average duration of Oppositions, from end of the filing period to the decision at oral hearing is ~ 19 months

Anonymity – Oppositions can be filed in the name of a ‘straw man’ e.g. Oxon IP, hiding the true identity of the opponent

No Litigation Estoppel – if unsuccessful, the same arguments and evidence can be used before national courts

Cost Effective - a single action, a single low official fee and a single decision

Finality – when the EPO revokes a patent it is revoked in all states, even if it had survived national court revocation actions

As well as representing Opponents, we have an exceptional record in representing Patentees defending their European patents in Opposition proceedings. Our experience on both sides means we are adept at spotting the flaws in third party patents, as well as the holes in challenges against our clients' European patents.