The European Patent Office (EPO) confirmed in recently issued Decision G3/14 the practice highlighted in earlier decisions (T301/87), whereby establishing that during opposition proceedings of a European patent the Opposition Division of the EPO can only analyze the lack of clarity of the amended claims when the amendments made may introduce an alleged lack of clarity.

However, the Opposition Division of the EPO shall not examine the lack of clarity of claims which were worded as per grant and have not been amended during opposition proceedings. No third party will be able to file an opposition based on lack of clarity either because it is not grounds for opposition under Article 100 of the European Patent Convention.