T 0788/90 (Opposition by patent proprietor) of 28.10.1993

Summary of Facts and Submissions

I. The appellants filed an opposition against their own European patent No. 0 223 659 (granted on 26 April 1989 for application No. 86 402 288.4), seeking revocation of its Claim 1 as non- inventive over the prior art cited in their opposition and requesting that the patent be maintained with a new set of Claims 1 to 5.

II. The Opposition Division rejected the opposition. The appellants, in their capacity as opponents, appealed against that decision, citing in their statement of grounds a new document in support of their arguments.

III. During the appeal proceedings, the Board advised the parties of its view that Claim 1 of the amended set of claims did not appear inventive over the opponents' new document and another two new documents cited by the Board of its own motion under Article 114(1) EPC.

IV. Decision G 9/91 (OJ EPO 1993, 408) and opinion G 10/91 (OJ EPO 1993, 420) were handed down by the Enlarged Board of Appeal before this Board could rule on the present case. Since the Enlarged Board's decision and opinion found that for oppositions the principle of examination of the Office's own motion was of limited scope, and expressed doubts about the validity of decision G 1/84 (OJ EPO 1985, 299), and since the decision in the present case depends on how said Enlarged Board decisions and opinion are interpreted, this Board has advised the parties that it is referring this important point of law to the Enlarged Board of Appeal.

Reasons for the Decision

1. Under Article 112(1)(a) EPC, Boards of Appeal are empowered, during proceedings on a case, to refer questions of their own motion to the Enlarged Board of Appeal where a decision is required in order to ensure uniform application of the law or if an important point of law arises. In the case here at issue, the present Board's decision depends on the extent to which it is competent to examine of its own motion the patentability of the claims proposed and agreed to by the proprietors of the patent in question, who are simultaneously both appellants and respondents. To answer this question, decisions G 1/84 and 9/91 and opinion G 10/91 have to be interpreted.

2. Decision G 1/84 ruled that a European patent could be opposed by its own proprietor. It argued that opposition proceedings are not essentially contentious ones between conflicting parties where the deciding body takes a neutral position; rather they are investigative proceedings in which an opponent may play a completely passive role or even withdraw without thereby bringing them to an end (see Reasons, point 4).

Decision G 1/84 is based on the principle that an opposition, once filed, is examined by the EPO of its own motion. Once inquisitorial proceedings of this kind are under way, the opponent's role is only secondary. His identity is therefore unimportant; he serves only to set in motion proceedings which are then conducted by the Opposition Division and, subsequently, the Board of Appeal.

3. Decision G 9/91 and opinion G 10/91 however took a different view, namely that opposition proceedings essentially involve opposing parties, and the role of the Opposition Division and Board of Appeal is like that of a civil tribunal which has to treat both parties equally.

4. Where a proprietor files an opposition against his own patent, the division and board are no longer ruling on adversarial proceedings between two opposing parties.

5. The question thus arises whether decision G 1/84 can continue to be applied in the light of decision G 9/91 and opinion G 10/91, which are at odds with the reasoning behind it. The present Board considers this an important point of law which needs to be resolved.

6. If the Enlarged Board rules that a proprietor can admissibly oppose his own patent, this would raise the question of the application to such a case of the principles laid down in decision G 9/91 and opinion G 10/91. These found that the competence of the Opposition Division or the Board of Appeal depends upon the extent to which the patent is opposed in the notice of opposition. They also acknowledged however that claims depending on an independent claim which falls in opposition or appeal proceedings may be examined as to patentability even if they have not been explicitly opposed, provided their validity is prima facie in doubt on the basis of already available information. The basis for extending the opposition's scope in this way to include dependent claims was that these were implicitly covered by the statement of opposition to the independent claim (see Reasons, point 11 of the decision and opinion).

7. Thus the legal basis given in decision G 9/91 and opinion G 10/91 to justify the competence of the Opposition Division and Board of Appeal to examine dependent claims is that opposition to the independent claim implicitly requests their revocation as well. This can hardly be the case however where a proprietor, in his capacity as opponent, is requesting limitation of his own patent but expressly restricts his opposition's scope to said limitation.

8. Furthermore, where a proprietor/opponent requests limitation of claims on the basis of prior art he has chosen himself, in the large majority of cases the validity of limited claims examined on the basis of such prior art can clearly not be considered as prima facie in doubt.

9. In such circumstances, the effect of applying the principles of decision G 9/91 and opinion G 10/91 to an opposition filed by a proprietor against his own patent would be to enable him to limit his patent without any possible scrutiny of the unopposed claims, as both the Opposition Division and the Board of Appeal would be bound by his original requests.

This raises the question of the compatibility of such limitation proceedings with the general principles of examination and opposition established by the EPC. As indicated in G 1/84, the EPC - unlike the Community Patent Convention (CPC) - contains no provision enabling a proprietor to request limitation of his own patent. In the CPC, such a request is subject to examination to determine whether the grounds for revocation under Article 56(1)(a) to (d) CPC - which correspond to the grounds for opposition laid down in Article 100 EPC - prejudice maintenance of the Community patent as amended (see Article 52(1) CPC).

ORDER

The following questions are referred to the Enlarged Board of Appeal:

1. Given the Enlarged Board of Appeal's new interpretation in decision G 9/91 and opinion G 10/91 of the basis for the opposition procedure, can a European patent be opposed by its own proprietor?

2. If so, do the Board of Appeal's powers of review in such a case depend on the extent to which the patent was opposed in the notice of opposition?