10.1 General remarks 

A fee that has been validly paid (see A‑X, 7.1.1) is not refunded. For instance, a validly paid further processing fee is not refunded if the request for further processing is rejected due to non-completion of the omitted act, which is another requirement of Rule 135(1) (see E‑VIII, 2). As an exception to this general principle, a validly paid fee is refunded if there are special provisions for the refund in either the EPC or the Rules relating to Fees (see A‑X, 2 A‑X, 10.2).

By contrast, any fee that has not been validly paid is to be refunded (see A‑X, 10.1.1 to A-X, 10.1.3 below). For the repayment of renewal fees not due, see A‑X, 5.1.1 and A‑X, 5.2.4.