T 2702/19 - Open-ended range

Key points

• "Claim 1 of the granted patent defines a medical device comprising a visualisation probe comprised of illumination means, an objective lens assembly and a CMOS sensor.
• "The respondent [opponent] argued that the patent did not disclose how to carry out the invention as defined in claim 1 over the whole scope thereof. In particular, it was not disclosed how to carry out the invention for very small values of the maximum outer diameter of the medical device, i.e. for values below 1 mm or even below 0.5 mm, which fell under the terms of claim 1. Furthermore, no reasonable lower limit for the maximum outer diameter of the medical device was known or derivable from the patent."
• "The board is not convinced by the patent proprietor's argument that the person skilled in the art would understand from the example given in the patent of a 0.5 x 0.5 mm CMOS sensor that this is the smallest implementable size of a CMOS sensor and that lower values would be nonsensical."
• The Board: "In conclusion, the person skilled in the art would not be able to derive from the patent, using their common general knowledge, a limit for the values of the maximum outer diameter of the medical device below which they would immediately exclude variants as being clearly outside the scope of practical application of the claimed subject-matter and thus could not justify an objection of insufficiency of disclosure. As argued by the respondent, the patent does not disclose how to carry out the invention over the whole effective claimed range of the maximum outer diameter of the medical device, i.e. also for values of this maximum outer diameter below 1 mm or even below 0.5 mm. Therefore, the ground for opposition under Article 100(b) EPC prejudices the maintenance of the patent as granted." 
• "Claims may be considered insufficiently disclosed if they cover, through open-ended ranges, embodiments that could not be obtained with the process disclosed in the patent, but which might be obtainable with different methods still to be invented in the future (see decision T 1697/12, points 5.5.3 and 5.5.4 of the Reasons; see also Case Law, II.C.5.5.2)."
• Are the Boards getting stricter on open-ended ranges? 
• Note that in T 595/95, allowed claim 1 specified: "A grain oriented silicon steel sheet having an iron loss at W17/50 of less than 0.90 W/kg,"

EPO 

The link to the decision and an extract of it can be found after the jump.

https://www.epo.org/en/boards-of-appeal/decisions/t192702eu1

6. Patent as granted - insufficiency of disclosure (Article 100(b) EPC)

6.1 The ground for opposition under Article 100(b) EPC prejudices the maintenance of the European patent if it does not disclose the invention in a manner sufficiently clear and complete for it to be carried out by the person skilled in the art.

The claimed invention must be sufficiently disclosed, based on the patent specification as a whole, including examples, and taking into account the common general knowledge of the person skilled in the art. At least one way of enabling the person skilled in the art to carry out the invention must be disclosed, but this is sufficient only if it allows the invention to be performed in the whole range claimed (see Case Law, II.C.1).

An objection of lack of sufficiency of disclosure presupposes that there are serious doubts, substantiated by verifiable facts, and it depends on the evidence available in each case whether or not a claimed invention can be considered as enabled on the basis of the disclosure of one worked example (see e.g. decisions T 226/85, OJ EPO 1988, 336; T 409/91, OJ EPO 1994, 653; and T 694/92, OJ EPO 1997, 408; see also Case Law, II.C.5.3).

It is established case law of the boards of appeal that the requirements of sufficiency of disclosure are met if the person skilled in the art can carry out the invention as defined in the independent claims over the whole scope of the claims without undue burden using their common general knowledge (see e.g. decisions T 409/91; T 435/91, OJ EPO 1995, 188; see also Case Law, II.C.5.4).

Claims may be considered insufficiently disclosed if they cover, through open-ended ranges, embodiments that could not be obtained with the process disclosed in the patent, but which might be obtainable with different methods still to be invented in the future (see decision T 1697/12, points 5.5.3 and 5.5.4 of the Reasons; see also Case Law, II.C.5.5.2).

6.2 In opposition proceedings, the burden of proof initially lies with the opponent, who must establish, on the balance of probabilities, that a skilled person reading the patent, using common general knowledge, would be unable to carry out the invention. This means that the opponent initially also bears the burden of proving that the invention cannot be carried out within the whole range claimed (see also Case Law, II.C.8.1).

When the patent does not give any information as to how a feature of the invention can be put into practice, only a weak presumption exists that the invention is sufficiently disclosed. In such a case, the opponent can discharge its burden of proof by plausibly arguing that common general knowledge would not enable the skilled person to put this feature into practice.

If the opponent has discharged its burden of proof and so conclusively established the facts, the patent proprietor then bears the burden of proving the alleged facts. It is then up to the patent proprietor to prove the contrary, i.e. that the skilled person's common general knowledge would enable them to carry out the invention (see Case Law, II.C.9.1).

6.3 Claim 1 of the granted patent defines a medical device comprising a visualisation probe comprised of illumination means, an objective lens assembly and a CMOS sensor.

Claim 1 of the granted patent specifies that "said medical device satisfies the condition that its maximum outer diameter is 3,2mm or less".

6.4 The respondent argued that the patent did not disclose how to carry out the invention as defined in claim 1 over the whole scope thereof. In particular, it was not disclosed how to carry out the invention for very small values of the maximum outer diameter of the medical device, i.e. for values below 1 mm or even below 0.5 mm, which fell under the terms of claim 1.

Furthermore, no reasonable lower limit for the maximum outer diameter of the medical device was known or derivable from the patent.

6.5 The appellant argued that according to claim 1, the medical device comprised a visualisation probe which in turn comprised illumination means, an objective lens assembly and a CMOS sensor.

According to the patent, these components of the visualisation probe, and in particular the CMOS sensor having a certain number of pads, had certain minimum sizes.

The presence of these components and the minimum dimensions thereof as required by the claim defined an implicit lower limit for the maximum outer diameter of the medical device.

6.6 The board is not convinced by the patent proprietor's argument that the person skilled in the art would understand from the example given in the patent of a 0.5 x 0.5 mm CMOS sensor that this is the smallest implementable size of a CMOS sensor and that lower values would be nonsensical.

It would not be unreasonable to try to further reduce the size of the CMOS sensor by using fewer pixels at a given pixel size. This is because paragraph [0007] of the patent discloses that "a compromise must be made based on the primary goal of the device, i.e. whether a small diameter is more important than a high-quality image". Hence, the board finds that the person skilled in the art would have understood that the sensor size may be further reduced at the expense of image quality.

There is a lower limit to the number of pixels because otherwise the resolution would have been too low and the space needed for the illumination means would have been too large in relation to the size of the CMOS sensor. However, it is not apparent to the board where this limit is because there is no clear boundary between when a visualisation probe could and could not be considered to yield insufficient image quality. Therefore, no clear limit can be derived from this consideration as to which sensor sizes the person skilled in the art would exclude as nonsensical.

The board is also not convinced that the situation dealt with in decision T 2773/18 is comparable with the case at hand because in that decision the relevant claim did not contain an open-ended range.

6.7 The board agrees with the patent proprietor that the number of pads on the back side of the silicon substrate specified in claim 1 (three or four) and their minimum size may imply a lower limit to the CMOS sensor size. However, even if the person skilled in the art were to interpret the phrase in paragraph [0009] of the patent "Since current technologies suggest that each pad has a minimum dimension (150 to 350 microns)" as defining what could be implemented on the priority date of the patent and take these values as read, the board is not convinced that the person skilled in the art would rule out any values below 150 microns as nonsensical. Therefore, the board is not convinced that the person skilled in the art could derive from this phrase an implicit lower limit for the maximum outer diameter of the medical device comprising a visualisation probe below which the person skilled in the art would consider the values to be nonsensical.

6.8 In conclusion, the person skilled in the art would not be able to derive from the patent, using their common general knowledge, a limit for the values of the maximum outer diameter of the medical device below which they would immediately exclude variants as being clearly outside the scope of practical application of the claimed subject-matter and thus could not justify an objection of insufficiency of disclosure. As argued by the respondent, the patent does not disclose how to carry out the invention over the whole effective claimed range of the maximum outer diameter of the medical device, i.e. also for values of this maximum outer diameter below 1 mm or even below 0.5 mm. Therefore, the ground for opposition under Article 100(b) EPC prejudices the maintenance of the patent as granted.