What language must I use when filing an international application if I want to participate in the IP Australia-EPO pilot?

If you file with the RO/AU the filing language of your international application must be English, which is one of the EPO’s official languages. Therefore, if you select the EPO as ISA, no translation is required, neither in the international nor in the European phase. If you file with the RO/IB, your international application can be filed in any language. If it is not one of the EPO’s official languages (English, German or French), a translation into an EPO official language must be filed (Rule 12.3 PCT) if you select the EPO as ISA.