The Schedule of fees of the EPO has two amounts for the appeal fee. A small fee for natural persons or small entities, as defined in Rule 6(4) and (5) EPC, and a large fee for everybody else. What happens, if you accidently declare yourself a small entity, even though you are a large entity, and thus pay the wrong fee? When filing an appeal to an opposition this happened to the unlucky appellant. In this case the appeal was deemed not filed. In particular, an attempt to correct under Rule 139, was dismissed as the correction was not filed quickly enough.
In the decision, the Board goes through of the ways in which this may be rectified, but comes to the conclusion that none apply. The decision has the following abstract (translated from the German):
For the question of the insignificance of the difference between the full appeal fee and the appeal fee, see Reasons No. 4.8.
On the question of an implicit request for correction of a debit order and the timeliness of the submission of a request for correction, see Reasons 5.7 to 5.14.
On the issue of ex officio correction of amounts in debit orders, see Reasons 6.1 and 6.2.
For the question of interpretation of a debit order with regard to the appeal fee, see Reasons No. 8.4.
Below a machine translation of the sections cited in the abstract is provided, and below that, the original German.