4. Correction of errors in the description, claims and drawings – Rule 139 EPC
4.5. Correction of errors in the description, claims and drawings after grant, and in opposition proceedings
In J 42/92 the board had to decide whether a request under R. 88, second sentence, EPC 1973 could be made after grant. It came to the conclusion that a request under R. 88 EPC 1973 for amendments to the description or claims could only be filed during the pendency of application or opposition proceedings. Under Art. 97(4) EPC 1973, the decision to grant a European patent took effect on the date on which the European Patent Bulletin mentioned the grant. After this date, R. 88 EPC 1973 could only be applied while opposition proceedings were pending. In the case at issue, the decision to grant the patent had already taken effect, and no opposition had been filed. The appeal was therefore dismissed, since the EPO had ceased to have jurisdiction to consider a request under R. 88 EPC 1973 at the time when the request was filed (see also J 23/03 and T 493/08).
Note that G 1/10 (OJ 2013, 194) deals with the different fields of application of various provisions as compared with R. 140 EPC (formerly R. 89 EPC 1973), in particular R. 139 EPC (points 9 and 11 of the Reasons) and Art. 123 EPC (see point 13 of the Reasons).
In T 657/11 the board observed that according to G 1/10 R. 140 EPC was not available to correct the text of a granted patent and a request for such a correction was inadmissible whenever made, including after the initiation of opposition proceedings (likewise T 2051/10, T 164/14, T 1578/13). However, in the case at issue, the amendments went beyond the mere removal of an error; namely by limiting the claims to those granted as (process) claims 6-11. Hence the basis for the decision on the appeal (and, thereby, on the opposition) was no longer that for the decision to grant the patent-in-suit, which decision would definitely lose its effect and be replaced by a new decision. In such a situation any (further) amendment of the claims, even if it aimed at the removal of an obvious mistake in the claims as granted, did not constitute a correction of an error or a mistake in a decision of the EPO within the meaning of R. 140 EPC. The board held that in opposition proceedings mistakes or errors concerning the claims, the description or the drawings of the patent as granted could be removed either by an amendment occasioned by a ground of opposition under Art. 100 EPC (see R. 80 EPC) or, insofar as the mistakes or errors concerned texts or drawings which remained unamended, by way of a correction pursuant to R. 139 EPC (which applied independently of R. 80 EPC; see also T 556/13). See also T 164/14 and T 1578/13, in which, however, the boards ultimately did not decide whether corrections could be made under R. 139 EPC in the conditions set out in T 657/11, because, in any event, the mistakes at issue in those cases were not obvious.