EP 2 974 084 B1 relates to a noise reduction method and to systems to be used in hearing aids.
Brief outline of the case
The opposition was rejected and the opponent appealed.
Claim 1 as granted lacked IS over document of category X,Y mentioned on the SESR. The same applied to AR1-4. The remaining AR were not admitted.
The patent was thus revoked.
At stake is feature (e):
- “the step of attenuating the signals further includes determining the attenuation of selected frequencies based on the magnitude or power of the difference between the left and right microphone signals or a value derived from the magnitude or power of the difference between the left and right microphone signals.”
The board’s decision on the MR
The proprietor submitted that feature (e) provided the technical effect of an improved signal-to-noise ratio.
The board was not convinced that this alleged effect is credibly achieved over the whole scope of claim 1. This finding is based on fundamental ambiguities in the claim language which prevent the skilled reader from objectively deriving a technical function for feature (e).
In particular, claim 1 as granted is silent as to the purpose of the “determining” step – whether explicitly or implicitly. The claim only requires that an attenuation value be determined; it does not require this value to be applied in a way that would have any technical impact on the method’s operation.
Without any requirement for this value to be used in a technical feedback loop, the “determining” step could well serve, for example, a non-technical purpose, such as the mere logging or displaying of a value for a user’s information, without any functional impact on the noise-reduction process itself.
Consequently, the board found that feature (e) does not produce a credible technical effect over the whole scope of the claim. It must therefore be regarded as a non-functional modification of the disclosure in document D2, see, for example, also T 287/23, Reasons 2.8.2.
The absence of a credible technical effect over the whole range claimed has direct consequences for the application of the well-established problem-solution approach in the assessment of inventive step.
The board acknowledges that the case law has developed two main approaches for assessing inventive step in such situations.
Approach 1
The first approach, seen in decisions such as T 1179/16, Reasons 3.4.4 and applied by the OD in the present case, is to formulate the objective technical problem as “providing an alternative“, i.e. “how to provide an alternative noise reduction method”.
However, the board considered this approach problematic, at least in the present case, particularly as it can lead to paradoxical outcomes. The “teaching away” exception mentioned in Reasons 3.4.4 of T 1179/16, which was a point of contention between the parties, presupposes a technical, i.e. functional, reason for avoiding a feature. Yet, this creates a logical inconsistency if the feature itself has been determined to genuinely have no technical effect.
In the board’s view, the “teaching away” concept, when assessing inventive step under Art 56, must rather be based on technical reasons, but a truly non-functional feature cannot be the subject of a technical “teaching away“.
The board therefore holds that a distinction must be made between “functional alternatives” and “non-functional modifications“.
The formulation of the OTP problem as “providing an alternative” is only appropriate for the former. For the latter, a different approach is warranted.
Approach 2
In line with its established jurisprudence, see e.g. T 1465/23, Reasons 2.7 and 3.3.3, the board found that, where distinguishing features constitute non-functional modifications, the problem-solution approach can be concluded without the formulation of an artificial OTP.
Accordingly, an arbitrary and non-functional modification of the prior art cannot support an IS.
Application to the present case
Applying this latter approach to the present case, the board concludes that feature (e) is a non-functional modification of the system of D2.
Consequently, it cannot contribute to an IS.
Comments
The important passage in Reasons 3.4.4 of T 1179/16 reads: “if the only contribution of the invention is to propose something different from the prior art, i.e. the provision of an alternative, then it is usually appropriate to consider that the skilled reader would take into account any alternative known in the underlying technical field, unless the closest prior art teaches away from it”.
The board considered that, in the absence of a technical effect, the OTP is not necessarily “providing an alternative”, but a distinction has to be made between “functional alternatives” and “non-functional modifications”.
Lack of IS can be decided in presence of “non-functional modifications” which should not be confused with “providing an alternative”.
It will have to be seen whether this approach will be taken over by other boards.
Comments
1 reply on “T 769/23-“Providing an alternative” is not necessarily the OTP”
A silly line of reasoning to try to reach a result that the board felt was “right”. We don’t need decades of case law explaining the difference “functional alternatives” and “non-functional modifications”. Such a distinction is arbitrary. The problem-and-solution approach is perfectly capable of handling “alternatives” without adding more layers of complexity and uncertainty.