EP Case Law in Brief: Erroneous Disclosures


Mistakes in a document do not in themselves constitute prior art such as to prevent the grant of a patent.

So begins section I.C. 4.9 of the Case Law of the Boards of Appeal. This statement, and the accompanying case law, provides for the possibility of a ‘get out of jail free card’ for novelty objections in certain circumstances.

An invention is "considered to be new if it does not form part of the state of the art". The "state of the art" is defined as "everything made available to the public by means of a written or oral description, by use, or in any other way, before the date of filing of the European patent application" (Art. 54 EPC). However, if the prior art document contains a mistake recognisable by the skilled person, the case law of the Boards of Appeal consistently confirms that the erroneous disclosure in said document does not constitute prior art such as to prevent the grant of a patent.

In particular, in decision T 230/01, the Board of Appeal found that a document does not form part of the state of the art if “it can unequivocally be proven that the disclosure of the document is not enabling, or that the literal disclosure of the document is manifestly erroneous and does not represent the intended technical reality. Such a non-enabling or erroneous disclosure should then not be considered part of the state of the art” (emphasis added).

Thus, in T 230/01, the Board defines two circumstances in which a disclosure should not be considered part of the state of the art:

(1) when the disclosure is manifestly erroneous and does not represent the intended technical reality, and

(2) when the disclosure is not enabling.

In this article, we focus on case law discussing when a disclosure is deemed manifestly erroneous, i.e. circumstances that fall under criteria (1) above.

In T0591/90, the Board took the view that a document is normally considered prior art even if its disclosure is deficient. “In evaluating the disclosure, it was to be assumed that the skilled reader was mainly ‘interested in technical reality’” (emphasis added). Therefore, using his general technical knowledge and consulting the reference literature, if the skilled person could see that the information disclosed was not correct, then that information did not form part of the prior art. The skilled person would “try to correct recognisable errors”, but not “take the deficient disclosure as pointing the way towards a solution to an existing technical problem”.

This was confirmed in T0412/91, where the Board stated that what has to be assessed is what the disclosure of a prior art document “revealed to the skilled person as a matter of technical reality” (emphasis added), not just “the words actually used”. If a statement is “plainly wrong, whether because of its inherent improbability or because other material shows that it is wrong, then although published it does not form part of the state of the art”. If, on the other hand, the skilled person cannot see that the disclosure is erroneous, the disclosure does form part of the state of the art.

Importantly, in T0161/98, the Board made it clear that when wrong statements are made in a document, “[w]hat does not belong to the state of the art is the wrong information, and not the whole technical teaching of the document”.

Related, contemporaneously available evidence may be relied on to shown that a disclosure is erroneous and does not represent the intended technical reality (T 77/87). Of note, the filing of declarations to contest a disclosure has generally not been found convincing by the Boards. Declarations have been qualified as “personal evaluations” and “subjective opinions” (T1009/97).

T 77/87 dealt with a specific situation of conflicting disclosures where only one could be true. Specifically. a published abstract did not correctly reproduce the original paper. The Board held that “it was clearly the disclosure of the original document that had to prevail” (emphasis added). This is because the original paper was “the primary source of what had been made available”.

T1080/99 also dealt with a conflicting disclosure of an abstract of a Japanese patent document and the corresponding full Japanese patent application. The Board noted that “if an abstract appears to add something to the original document then this points to an error in the abstract, or at least to an error in its interpretation”. This differed from T0160/92 where  “only the Japanese abstract was on file and there was no indication that its disclosure might be erroneous or might otherwise have to be interpreted differently in the light of the disclosure of the original document”.

In T1015/03, a prior art document disclosed contradictory statements with regard to the concentration of an agent in a composition. The Board found that this internal discrepancy led to an ambiguous teaching since it was unclear which concentration values were correct. Consequently, the prior art document was not considered to form part of the state of the art. Similarly, in T0412/91, the Board found that contradictory values would lead the skilled person to correct values in a GB patent application in light of the US equivalent document.

A review of Appeal Board decisions is provided in the briefing here. The review includes the type of document which recites the alleged erroneous disclosure, the evidence provided, as well as the Board’s comments.