More rule changes for the better at the EPO
Lack of unity and further searches in the regional phase
Applicants may enter the European regional phase at the European Patent Office (EPO) from a PCT application. The EPO may or may not have acted as the International Searching Authority (ISA) for the PCT application.
Currently under Rule 164 EPC, when the EPO is not the ISA, the EPO will carry out a supplementary search. If the patent application is considered by the EPO search examiner not to comply with the requirement for unity of invention, the supplementary European search report will only be drawn up on the parts of the application which relate to the invention first mentioned in the claims. Any further invention can only be prosecuted by filing a divisional application, which is costly...
More information here.