The protest fee is paid for the benefit of the IPEA/EP and its amount is fixed by the EPO. It is payable within one month from the date of the invitation to pay additional examination fees after a finding of lack of unity (Form PCT/IPEA/405, see GL/PCT‑EPO C‑V, 4.3). The amount payable is the amount applicable on the date of payment.[Rule 68.3(e); ]