The boards' previous case law, that it could be within the scope of R. 89 EPC 1973 (now R. 140 EPC) to correct the text of a patent if it was not, and obviously could not be, in the form intended by the decisionmaking department (classic examples of such rulings being T 850/95, OJ 1997, 152; T 425/97, T 965/98), was radically changed by G 1/10. The boards in T 367/96 and G 1/97 (OJ 2000, 322) had already held previously that R. 89 EPC 1973 had to be interpreted narrowly and, accordingly, only allowed for the correction of formal errors in the written text of the decision notified to the parties in accordance with R. 68 EPC 1973 (now R. 111 EPC). It did not, however, pave the way for reexamination of the factual or legal issues on which a decision was based, nor for reversal of any conclusion derived by the decisionmaking department from a consideration of these issues.
In G 1/10 (OJ 2013, 194), however, the Enlarged Board went further, holding that, since R. 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 during opposition or limitation proceedings. The Enlarged Board's decision was limited to corrections of grant decisions, more precisely to corrections within grant decisions of the description, claims and drawings (patent documents), and not concerned with corrections of bibliographic data.
The Enlarged Board of Appeal pointed out that legal certainty and the prevention of adverse effects on third parties were the reasons for the narrow ambit of allowable corrections under R. 140 EPC (see G 1/97, travaux préparatoires). It agreed with the statement in T 850/95 that patent documents referred to in a grant decision become an integral part of the decision, but did not agree with the subsequent conclusion that errors in those documents may subsequently be corrected under R. 140 EPC.
The Enlarged Board stated that the absence of a possibility to request patent corrections under R. 140 EPC should not prejudice patent proprietors. If a correction is obvious (as it should be to satisfy R. 140 EPC) then there will be no surprise or adverse effect on opponents or others, because all concerned should read the patent as if corrected and an actual correction is unnecessary. If, however a correction is less than immediately obvious, it should not be allowed under R. 140 EPC anyway, which is confined to correction of "obvious mistakes". If, given the opportunity to check the patent text before approving it, an applicant does not draw any errors to the attention of the examining division and thus ensures that his approval is limited to the correct text, then the responsibility for any errors remaining in that text after grant should be his alone, whether the error was made (or introduced) by him or by the examining division.
If however the examining division proceeds to make a decision to grant which contains an error subsequently made by it, so that the granted text is not that approved by the proprietor, then the proprietor is adversely affected by that decision and is entitled to appeal. A patent proprietor may seek to amend his patent during opposition or limitation proceedings and such an amendment could remove a perceived error, however, it would have to satisfy all the legal requirements for amendments including Art. 123 EPC.
In T 212/88 (OJ 1992, 28) the board held that the absence of a chairman's or minute-writer's signature at the end of an opposition division's decision was a rectifiable, obvious error within the meaning of R. 89 EPC 1973 (now R. 140 EPC). In the case in question a second examiner had been referred to in the minutes as a member of the opposition division, although in fact he was not a member and did not take part in the oral proceedings (see also T 212/97). The board held that correction of the two errors had to be by means of a decision under R. 89 EPC 1973 with retrospective effect from the date of the original decision. The same board emphasised the retrospective effect of corrections under R. 89 EPC 1973 in T 116/90 but stated that it was unnecessary to re-date the decision as from the date of correction. In T 212/97 the board pointed out that R. 89 EPC 1973 (now R. 140 EPC) permitted the opposition division to correct an obvious mistake in the copy of the decision notified to the parties. In the case at issue, a fourth person had been named as a member of the opposition division although no such person had been mentioned in the original document.
In T 867/96 the patentee had requested the correction under R. 89 EPC 1973 (now R. 140 EPC) of a sentence, in the reasons for a board of appeal decision, stating that all the parties had agreed that a certain document represented the closest prior art. The board pointed out that the case was closed, as res judicata, and therefore no longer before it. Citing in particular G 8/95 (OJ 1996, 481) and G 1/97 (OJ 2000, 322), the board held that only the board which had taken a decision could decide whether it required correction. Furthermore, establishing whether correction was necessary involved studying the facts, implying in general and up to a certain point that such requests were admissible. The current board thus ruled that the request for correction was admissible. However, it also held that this particular request did not fulfil the requirements of R. 89 EPC 1973, was unfounded and should therefore be refused.
In T 425/97 the board referred to G 8/95, which dealt with the scope of R. 89 EPC 1973 (now R. 140 EPC), stating that the difference between an appeal against a decision and a request for correction of a decision might be seen in the fact that in the first case the remedy was directed against the substance of the decision and in the latter case against the form in which the decision was expressed. In another decision issued prior to G 1/10, the board in T 1093/05 (OJ 2008, 430) similarly held that, if a grant decision was defective, the patent proprietor had to consider carefully the nature of the defect and how it could best be rectified. If it involved a substantial procedural violation, rectification was possible only on appeal. A request for correction under R. 89 EPC could succeed only if it was clear that the examining division had not intended to grant the patent in that form – and also in what form it had intended to grant it.