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12 September, 2012

In a recent decision (G1/10) the Enlarged Board of Appeal at the European Patent Office (EPO) has confirmed that Rule 140 EPC is not available to correct the text of a granted patent and that a patent proprietor’s request for such a correction is inadmissible whenever made.

Rule 140 EPC provides that: “In decisions of the European Patent Office, only linguistic errors, errors of transcription and obvious mistakes may be corrected”.

In this case, an opposition was based solely on the argument that claim 1 of the patent as granted contained added subject-matter. The patent proprietor argued that this resulted from a typographical error during prosecution and requested that the opposition be stayed and that the patent be sent back to the examining division for re-issuance after correction under Rule 89 EPC 1973 (which corresponds to Rule 140 EPC).

The opposition division took the interlocutory decision to stay opposition proceedings, to remit the case to the examining division for a decision on the request for correction under Rule 140 EPC, and to allow a separate appeal against this decision. The opponent appealed against the decision. Concerned that the opponent could be left without legal remedy in the event that the examining division corrects a granted patent under Rule 140 EPC, the Technical Board of Appeal referred the following questions to the Enlarged Board of Appeal:

1. Is a patent proprietor’s request for correction of the grant decision under Rule 140 EPC which was filed after the initiation of opposition proceedings admissible? In particular, should the absence of a time limit in Rule 140 EPC be interpreted such that a correction under Rule 140 EPC of errors in decisions can be made at any time?

2. If such a request is considered to be admissible, does the examining division have to decide on this request in ex parte proceedings in a binding manner so that the opposition division is precluded from examining whether the correction decision amounts to an unallowable amendment of the granted patent?

In decision G1/10, the Enlarged Board of Appeal has answered the questions as follows:

1. Since Rule 140 EPC is not available to correct the text of a patent, a patent proprietor’s request for such a correction is inadmissible whenever made, including after the initiation of opposition proceedings.

2. In view of the answer to the first referred question, the second referred question requires no answer.

In reaching this conclusion, the Enlarged Board of Appeal reasoned that, although the description, claims, and drawings referred to in a grant decision are part of that decision, errors in those documents may not be subsequently corrected under Rule 140 EPC since the provision is intended for correcting errors in decisions of the EPO and not errors in documents filed by a patent application or proprietor.

In the Enlarged Board of Appeal’s opinion, a patent applicant or proprietor is considered to have adequate means at his disposal to ensure his patent as granted is in the exact form he wants it without any need to invoke Rule 140 EPC. For instance, should an applicant make a mistake in a document he has filed, at any stage up to final approval by him of the text of the patent, then that mistake can be corrected on request under Rule 139 EPC. Further, a patent applicant is obliged to approve the text in which his patent is to be granted. Thus, responsibility for any errors remaining in that text after grant are considered to be his alone, whether or not the error was introduced by him or by the examining division and it would be illogical to impute the mistake to the examining division in order to bring the applicant’s own error within the ambit of Rule 140 EPC.

Although Rule 140 EPC is not available for correcting granted patents, the Enlarged Board of Appeal noted that a patent proprietor may seek to amend his patent during opposition or limitation proceedings and such an amendment could remove a perceived error. Such an amendment would, of course, have to satisfy all the legal requirements for amendments, including both the prohibition of added subject-matter and the prohibition of post-grant broadening of the scope of the claims.

This decision serves as a reminder of the need to thoroughly check the text intended for grant accompanying the Communication under Rule 71(3) EPC.