There is no definition of equity in the EPC. The boards of appeal therefore had to develop the criteria determining whether costs were to be apportioned on a case-by-case basis. In a number of decisions it has generally been stated that apportionment of costs is justified if the conduct of one party is not in keeping with the care required, that is if costs arise from culpable actions of an irresponsible or even malicious nature (see, for example, T 765/89, T 26/92 and T 432/92).

Requests for a different apportionment of costs are often filed in various scenarios in which costs are incurred for:

- late submission of documents and/or requests (see in this chapter III.R.2.1.);

- acts or omissions prejudicing the timely and efficient conduct of oral proceedings (see in this chapter III.R.2.2.);

- filing of opposition or appeal (see in this chapter III.R.2.3.);

- withdrawal of opposition or appeal at short notice (see in this chapter III.R.2.4.);

- other cases (see in this chapter III.R.2.5.).