Why has my payment been rejected?

The validation functionality detects and automatically rejects the following: 

• the payment of renewal fees that are not due
• the payment of additional fees under Rule 51(2) EPC that are not due
• the double-payment of fees except those listed in Annex A.3 to the ADA
• the payment of fees for transfer of rights for definitively closed European patent applications
• the payment of fees for European patents with unitary effect that are not due
• will be automatically rejected."

The automatic rejection of payments reduces the administrative work involved in refunding invalidly paid fees, for both users and the EPO.