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T 1782/21 – Common general knowledge in case of lack of sufficiency - A patent is not representative of common general knowledge.

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The application relates to biometric authentication using vein patterns of e.g. a palm or a finger. The positions of the vein pattern for matching are normally defined in respect of the outline of the considered region, which requires the acquisition of the entire region. For speed reasons it is desired to perform vein authentication using partial patterns. The application proposes to use the surface skin patterns, such as skin wrinkles, and characteristic points thereof, to define positions of areas for vein pattern matching.

Brief outline of the case

The applicant appealed the ED’s decision to refuse the application for lack of compli­ance with Art 83.

During the appeal procedure, the applicant filed the following documents

D7=Tsuyoshi Takatani et Al., “Decomposition of reflection and Scattering by Multiple Weighted Measurements”, 2011, and

D8: Mizuki Watanabe et Al., “Examination of vein extraction by colour conversion and annealing method”, 15 March 2016, as well as


The board confirmed the refusal.

The ED’s position

The ED refused the application for lack of disclosure of the following claimed feature:

“a pattern extraction means (11, 12) configured to extract a surface pattern and a blood vessel pattern of a living body from a biometric image”

reasoning that the skilled person did not know, from the application, or from the common general knowledge, how to extract the two different patterns from one single image, e.g. how to separate the skin lines from the vein lines in figure 5.

The applicant’s position

In order to establish that the missing disclosure was indeed common general knowledge, the applicant referred to documents D7, D8 and D10.

Document D7

Document D7 discloses technologies where diffuse reflection and specular reflection are extracted from an image, see for example the abstract of document D7. Diffuse reflection corresponds to the vessel pattern of the independent claims in AR1, while specular reflection corresponds to the surface pattern.

Document D8

Document D8 discloses a technology in which a vein image is generated by using a red component and a green component which are extracted from an image. Although vein patterns are usually acquired using infrared light and detectors, the technology disclosed in document D8 was developed to allow identifying a vein pattern using visible light such as for example using digital cameras in a mobile phone.

Document D10

The filing of D10 was due to “the importance given by the board to the specific wavelengths used for obtaining the image in relation to document D8″, i.e. infrared and not visible light

During the OP the applicant further argued that the technical field of the application, i.e. biometric sensing and authentication, was a competitive and fast moving one, and suggested that, therefore, every patent would quickly become known in the interested circles. D10 was granted more than one year before the priority date of the application, during which time it could be assumed to have become known to the person skilled in the art.

The board’s position

It is undisputed that it is not self-evident how to extract from a single image, rather than from two separate ones, two biometric patterns which are formed, respectively, at the surface of a living body and below the surface (subcutaneously). It is also undisputed that the application does not provide any information on how to do this, and hence how to carry out the quoted claimed feature.

Document D7

The Board agreed that D7 shows that “separation of the diffusion reflection and the mirror reflection” was known, but, D7 makes no mention of the separation of vein from surface patterns.

The board was not convinced by the applicant’s statement that “Diffuse reflection corresponds to the vessel pattern … while specular reflection corresponds to the surface pattern” and, in view of the foregoing, that D7 discloses what is missing in the application at hand.

Document D8

The board noted that in D8, it is thought that a vein image cannot be captured without a near-infrared radiation in a conventional vein authentication technology … The present authors have been studied an algorithm for identifying a vein by limiting the visible light”.

For the board, D8 rather points out that standard technology required infrared light for vein pattern acquisition, which also corresponds to what the current application teaches when presenting the vein pattern acquisition.

Document D10

Although D10 could be dismissed under Art 13(2) RPBA, the board nevertheless admitted it.

It was clear from the applicant’s letter that the submission was pertinent to the discussion and why. The submission was filed sufficiently ahead of the OP for the board to have time to analyse it.

The board agreed with the applicant that D10 discloses that which is missing in the application. To overcome the insufficiency objection, however, it must also be shown that what D10 discloses constitutes common general knowledge.

The board held that certain knowledge is indeed common general knowledge is demonstrated by reference to encyclopaedias, textbooks, monographs or such like.

At the same time, patent literature such as D10 is normally not sufficient for this purpose. It has been accepted that in exceptional cases patents could represent common general knowledge. The board referred to T 412/09, reasons 2.1.3, 2d §, in which it was accepted that, exceptionally, a series of patent publications can be sufficient if it “provides a consistent picture that a particular technical procedure was generally known and belonged to the common general knowledge in the art at the relevant date”.

However, D10 is not only not a “series”, but also does not support the applicant’s view on common general knowledge. Specifically, D10 does not present the method in question as commonly known but as an invention made at the time

The applicant’s argument that the field is so competitive and fast moving that the skilled person would follow all developments and therefore get to know all new methods, including that of D10, soon after they are published was a mere allegation.

This allegation was not supported by any evidence. The board has no reason to believe that the field is special nor that D10 itself is.

Moreover, the extraordinary idea that any published patent application in some field might become common general knowledge in little time is not convincing, at least not in general.


The present case illustrates well that, when it comes to sufficiency, in case of fundamentally missing features, those missing features can possibly be compensated by true common knowledge.

The board confirmed that a patent document is in general not to be considered as representative of common general knowledge.

It is only in exceptional circumstances that a patent document can be representative of common general knowledge. Next to T 412/09, it is also possible to quote T 51/87, OJ 1991, 177, and T 1117/14.

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3 replies on “T 1782/21 – Common general knowledge in case of lack of sufficiency – A patent is not representative of common general knowledge.”

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