Responding to the written opinion or the International Preliminary Examination Report issued by the EPO

Question 2
Once the changes of the Implementing Regulations of the European Patent Convention comes into force on 1st April 2010, will it be mandatory to respond to the written opinion or the International Preliminary Examination Report issued by the EPO as the ISA upon entry into the European phase of a PCT application?

Answer 2
According to new Rule 161 EPC, for which the EPO acted as ISA (International Search Authority) or IPEA (“International Preliminary Examination Authority”), the EPO shall invite the applicant to respond within a period of one month from the date of the respective communication. The legal consequence of the failure to respond within the time limit is that the application shall be deemed to be withdrawn. This new rule will apply to European patent applications for which the ESR (“European Search Report”) or SESR (“Supplementary European Search Report”) is drawn up on or after 1 April 2010.
We recommend that a response to the written opinion or IPER issued by the EPO on or after 1 April 2010 should be considered prior to entry into the European regional phase, due to the very short time period available (i.e., one month) once the communication under Rule 161 is issued.