T 1450/16 (Acoustic port of a hearing device/SHURE) of 17.1.2020
The problem-solution approach is a well-known framework for the assessment of inventive step according to Article 56 EPC, but often leads to discussions of its correct application.
In the very beginning of this multi-step process, a document is selected to be the “closest prior art”, and on the basis of this document inventive step of the application is assessed.
The application in question concerns an earphone (in-ear headphone). The board in this case held that the closest prior art was a document D1 published in 1968 directed to a hearing aid.
The applicant however suggested that selection criteria for the closest prior art were as follows:
- The closest prior art should belong to the same technical field as the application.
- The closest prior art should relate to the same technical problem as the application in question.
- The number of features in common between the application and the closest prior art should exceed the number of features shared with other documents.
The applicant thus concluded that the person skilled in the art would not have chosen D1 as closest prior art.
The board, however, did not agree that the person skilled in the art could be the person who selects the closest prior art. According to the board, this would mean that “the same (fictitious) person as the one who finally assesses the obviousness of a certain claimed subject-matter has already selected their “favourite” prior-art document in order to conduct that assessment.” This would render the approach subjective.
The board remains that the skilled person should only enter into the problem-solution approach once the objective technical problem has been formulated. The board concludes therefore that “it must be the respective deciding body – be it the examining division, the opposition division or the relevant board of appeal – who selects the closest prior art rather than the skilled person mentioned in Article 56 EPC.”
Based on the prior art chosen by the board, none of the presented claims were allowable under the Article 56 EPC and the appeal was dismissed.
