The renewal fee for the third year can always be validly paid until the due date under
Rule 51(1) EPC. If, however, the renewal fee for the third year fell due within the 31-month time limit for entry into the European phase, the due date is deferred and the fee may be paid without surcharge up to expiry of the 31-month time limit. In that case the grace period of six months within which the renewal fee can still be validly paid, subject to payment of a 50% additional fee, is computed from the date of expiry of the 31-month time limit.