Mathys & Squire analyses the changes to the EPO’s opposition procedure and suggest ways in which businesses can align their strategy with the current legal tools availableOpposition procedure at the European Patent Office (EPO) has long been a relatively cost-effective and efficient way to invalidate patents, especially compared to litigating a European patent in even a single European national court, let alone litigating in every relevant European jurisdiction. Recent changes in EPO procedure have made it an even more attractive tool for protecting business interests from competitors’ patents.Why oppose?For those who are not already familiar with it, the European opposition procedure is intended to allow any third party to seek revocation of a granted patent within nine months of grant. This can result in complete revocation, or limitation. The process can bring to the EPO’s attention circumstances, normally prior art, of which the EPO was not previously aware. It allows competitors to put forward evidence of prior use that is generally not documented in search databases, or evidence of insufficiency backed up by experimental data, which is also not within the scope of normal examination at the EPO. It is also common for other parties to take a harsher view of novelty or inventive step or the formal compliance of amendments (added matter) than the examiner took.There are a number of commercial reasons why oppositions are filed. An obvious reason is that the opponent is directly concerned that they may infringe the patent. It is worth noting that opposition proceedings at the EPO have the advantage of effectively being launched anonymously (via a straw man) and thus filing an opposition does not immediately indicate to a proprietor the identity of a possible infringer. This is an important contrast to court proceedings for invalidation which are likely to provoke a counterclaim for infringement and tend to become rapidly more expensive and build momentum.To read the full article which first appeared in Managing Intellectual Property in December 2018 click here.