A. The principle of the protection of legitimate expectations

1.Applicability of the principle of the protection of legitimate expectations

1.1.Sources of legitimate expectations

1.2.Limits of the legitimate expectations principle

1.2.1Knowledge of the relevant legal provisions and the case law

1.2.2Interpretation of substantive patent law

1.2.3Weighing of interests in inter partes cases

1.2.4Area of party's own responsibility

1.2.5Administrative notice with no legal consequences

1.3.Causal link and the requirement of proof

2.Information provided by EPO

2.1.Clear and unambiguous communications and forms

2.2.Information provided as courtesy service

2.3.Contradictory acts

2.4.Information provided by telephone

2.5.Decisions of the department of first instance

2.6.Correction of already issued decision

2.7.Information provided in the Guidelines

3.Obligation to draw attention to easily remediable deficiencies

3.1.General principle

3.1.1Deficiency correctable within the relevant time limit

3.1.2Obligation to set new time limit

3.2.Examples of cases addressing the obligation to draw attention to easily remediable deficiencies

3.2.1Language issues

3.2.2Missing or insufficient fee payments

3.2.3Electronic filing of documents

3.2.4Further examples involving easily identifiable deficiencies

3.3.Limits of the obligation to draw attention to easily remediable deficiencies

3.3.1Area of party's own responsibility

a)Filing of valid appeal

b)Filing of divisional application

c)Bank account information

3.3.2No obligation to scrutinise submissions for deficiencies

4.Obligation to enquire in case of unclear nature of request

5.Legitimate expectation and case law

5.1.Case law deviating from or overruling the practice

5.2.Point in time from which a new decision which deviates from existing practice becomes generally applicable

The principle of the protection of legitimate expectations is a general principle well established in European Union law and generally recognised in the EPC contracting states and board of appeal case law (G 2/97, OJ 1999, 123; see also R 4/09). Its application to procedures before the EPO implies that measures taken by the EPO should not violate the reasonable expectations of parties to such proceedings (G 5/88; G 7/88; G 8/88, OJ 1991, 137). The term "good faith" is also used to describe this concept (J 10/84, OJ 1985, 71; J 38/97; J 19/13; J 19/16).

The protection of the legitimate expectations of users of the European patent system has two main principles. It requires that the user must not suffer a disadvantage as a result of having relied on erroneous information or a misleading communication received from the EPO (see in this chapter III.A.2.). It also requires the EPO to warn the applicant of any loss of right if such a warning can be expected in good faith. This presupposes that the deficiency can be readily identified by the EPO (see in this chapter III.A.3.).

Users of the European patent system, who are parties in proceedings before the EPO, must also act in good faith (G 2/97, R 4/09, T 861/12). An alleged violation of the principle of the protection of legitimate expectations is in itself not a ground for a petition for review under Art. 112a EPC (R 13/11, R 1/16).