A written opinion for the purposes of international preliminary examination is a notification issued by the IPEA which indicates any comments or objections concerning the international application. Pursuant to Rule 66.1bis(a) PCT the WO-ISA is considered to be a (first) written opinion of the IPEA for the purposes of international preliminary examination. The EPO has notified the International Bureau under Rule 66.1bis(b) PCT that this provision is only applied by the EPO as IPEA to the extent that the WO-ISA has been established by the EPO acting as ISA.