T 1450/16 - We decide what the CPA is

Key points

• This examination appeal is about inventive step. Claim 1 is directed to an earphone. The Examining Division considered D1 to be the closest prior art.
• The applicant: “Given that earphones and hearing aids were very different apparatuses, document Dl, being directed to a hearing aid of 1968, was an unrealistic starting point for an application directed to an earphone for sound reproduction.”
• “The board is not persuaded by these arguments for the following reasons.”
• “This board [3.5.03] follows the conclusions drawn, for example, in T 422/93-3.3.01 (see Headnote 1)  [i.e. T 422/93, taken by Board 3.3.01] and T 1140/09-3.4.03 (see Reasons 4.4) that the relevant skilled person is to be defined starting from the objective technical problem. As a consequence, in the board's view, the person skilled in the art within the meaning of Article 56 EPC enters the stage only when the objective technical problem has already been formulated.” (emphasis added)
• “Thus, the skilled person under Article 56 EPC is the person qualified to solve the established objective technical problem [] and not necessarily the person versed in the field of the underlying application or in the field of the selected closest prior art [].
  In conclusion, this board considers that it must be the respective deciding body [board or first instance division] who selects the closest prior art rather than the skilled person mentioned in Article 56 EPC [].”
• I'm not entirely sure how the Board here takes into account that the skilled person is merely notional. The phrase that the skilled person 'decides' something is of course merely a figure of speech; it's the actual humans taking the decision (e.g. the Board members Bengi-Ayürek, Peirs and Romandini in this case) that decide.  
• “The closest prior art D1 discloses the following limiting features of claim 1 of the main request (as labelled by the board): (a) an earphone (page 2, lines 7-9: "hearing-aid") for sound reproduction”
• I suppose that if you interpret the claim feature 'earphone' to encompass 'hearing-aid', the applicant's argument that these are different things indeed does not work.
• The Board also writes in another paragraph (r.2.1.6): “This is all the more so since "hearing aids" and "earphones" are similar in structure” (emphasis added). How a  prior art document mentioning 'hearing-aid' therefore takes away the novelty of the claim feature 'earphone', if hearing aids and earphones are (not identical but only) 'similar' in structure is a question I must leave as an exercise for the reader.
• The Board: “It is generally accepted that the closest prior art is that prior art which, within a single reference, discloses the combination of features which constitutes the most promising starting point for a development leading to the invention.
  One of the established criteria for selecting that starting point is that the closest prior art should typically relate to the same or at least a similar purpose as that of the claimed invention (see e.g. T 1841/11-3.4.03, [Headnote]).”
• I don't think it's a new observation, but saying that a document is the ‘closest prior art’ because it's the ‘most promising starting point’ begs the question how the Board knows that the document is the most promising starting point. 

EPO  T 1450/16 -  link

EPO Headnote
In the application of the problem-solution approach for the assessment of inventive step, the person skilled in the art within the meaning of Article 56 EPC enters the stage only when the objective technical problem has been formulated in view of the selected "closest prior art".
Only then can the notional skilled person's relevant technical field and its extent be appropriately defined. Therefore, it cannot be the "skilled person" who selects the closest prior art in the first step of the problem-solution approach. Rather, this selection is to be made by the relevant deciding body, on the basis of the established criteria, in order to avoid any hindsight analysis (see point 2.1.4 of the Reasons).


Reasons for the Decision

2. Main request: claim 1 - inventive step

The subject-matter of present claim 1 does not involve an inventive step, for the reasons set out below.

2.1 Selection of closest prior art

2.1.1 The board holds that, of the prior art to hand, document D1 constitutes the "closest prior art", the reasons being as follows.

2.1.2 The appellant contended that D1 was not the closest prior art on several grounds. It was evident from paragraph [05] of the description as originally filed, in particular from the formulation "[t]o reduce bulkiness and weight, in-the-ear speakers or earphones have been designed to replace headphones", that the claim, being directed to an "earphone for sound reproduction", was in no way intended to cover a "hearing aid". Given that earphones and hearing aids were very different apparatuses, document Dl, being directed to a hearing aid of 1968, was an unrealistic starting point for an application directed to an earphone for sound reproduction. In that context, the appellant named several selection criteria developed in the jurisprudence of the boards of appeal for choosing a particular document as the "closest prior art":

- A first selection criterion was that such a document should belong to the same technical field as the underlying application. The appellant argued that in the era before the advent of digital hearing devices, such as the 1970s, the 1980s and the 1990s, an earphone was very different from a hearing aid. It stressed that even today no hearing aid manufacturer was selling earphones and concluded that earphones and hearing aids were to be seen only as neighbouring fields.

- A second selection criterion was that the prior-art document should consider the same technical problem as the application in question. The appellant referred to paragraph [08] of the description as filed to underline that the present application aims "to provide a means for allowing a user to readily customize an earphone so that the sound reproduction fit[s] the user's musical tastes and hearing ability". Document D1, by contrast, dealt with a selection of soft rubber to avoid acoustic leakage and loss of resilience, as stated in lines 32-42 of page 1. Hence, D1 rather addressed material aspects.

- A third selection criterion was the number of features that the document has in common with the claim. The appellant argued that D1 was not closer than D5 or D6 in this respect.

From the above, the appellant concluded that the skilled person would not have chosen document D1 as the closest prior art. In particular, "the skilled person would not start from a hearing aid when confronted with an earphone" (see statement of grounds of appeal, page 4, first paragraph).

2.1.3 The board is not persuaded by these arguments for the following reasons. Since the proper selection of the closest prior art was an essential issue in the present case, the board finds it helpful to consider in more detail the jurisprudence of the boards of appeal in that respect.

2.1.4 First, the board does not agree with the assumption relied on by the appellant that, according to the basic problem-solution approach, the person skilled in the art may be entrusted with the task of selecting the closest prior art or a suitable starting point for the assessment of inventive step, which is the first step in the multi-stage method of that problem-solution approach (see e.g. R 5/13, Reasons 13). In the board's view, 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. Given that the objective technical problem is to be derived from the distinguishing features established with respect to the selected closest prior art, such a selection would further imply that this skilled person could pose the objective problem to him or herself. However, this would be at odds with the very aim of the

problem-solution approach, namely to provide an objective method of evaluating inventiveness, avoiding as far as possible an inadmissible hindsight analysis.

In that regard, the board is aware of case law which at least implicitly indicates that the skilled person may select their "own" closest prior art (see e.g. T 1841/11-3.4.03, Reasons 2.6, emphasis by the present board: "... choice of closest prior art, provided that it would be immediately apparent to the skilled person that what is disclosed in the document could be adapted to the purpose of the claimed invention in a straightforward manner ..."; T 2057/12-3.4.01, Reasons 3.2.2, last paragraph: "... why the skilled person ... would have indeed envisaged selecting a document ... as closest prior art ..."; T 1248/13-3.2.03, Reasons 2.1: "... It is indeed not apparent for which reasons the skilled person, who is a technician mainly active in the field of warheads ... would have envisaged applying the teaching of [closest prior art] D4 ..."). Rather, this board follows the conclusions drawn, for example, in T 422/93-3.3.01 (see Headnote 1) and T 1140/09-3.4.03 (see Reasons 4.4) that the relevant skilled person is to be defined starting from the objective technical problem.

As a consequence, in the board's view, the person skilled in the art within the meaning of Article 56 EPC enters the stage only when the objective technical problem has already been formulated. Thus, the skilled person under Article 56 EPC is the person qualified to solve the established objective technical problem (see e.g. T 32/81-3.2.01, Reasons 4.2; T 26/98-3.4.01, Reasons 6.3; T 1523/11-3.5.07, Reasons 4.4) and not necessarily the person versed in the field of the underlying application or in the field of the selected closest prior art, as apparently advocated in T 25/13-3.2.08 (see Reasons 2.4). In conclusion, this board considers that it must be the respective deciding body (whose members cannot be equated with the skilled person as a notional entity; see T 1462/14-3.4.01, Reasons 14 and 15) - 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, in accordance with the findings in T 855/15-3.5.06 (see Reasons 8.2).

2.1.5 It is generally accepted that the closest prior art is that prior art which, within a single reference, discloses the combination of features which constitutes the most promising starting point for a development leading to the invention. One of the established criteria for selecting that starting point is that the closest prior art should typically relate to the same or at least a similar purpose as that of the claimed invention (see e.g. T 1841/11-3.4.03, Catchword).

2.1.6 In the present case, when starting from claim 1 to select the closest prior art, the board does not accept the appellant's view that D1 is excluded from being a promising starting point since it was not related to the same or similar purpose. The hearing aid of D1 and the earphone of claim 1 both provide sound to a listener via an electro-mechanical acoustic transducer mounted in an electric device having a means for electrical amplification and being worn in the ear. Therefore, the claimed earphone and the hearing aid of D1 relate to the same purpose. Moreover, hearing aids and earphones are not to be regarded as neighbouring fields, but belong rather to the same technical field. This is all the more so since "hearing aids" and "earphones" are similar in structure (see the similar devices shown in the figures of the present application and in D1), in use (i.e. the present case relates mainly to an in-the-ear earphone and D1 relates to a hearing aid that is to be worn in the ear) and in function (i.e. both provide electrically amplified sound to a wearer).

2.1.7 In addition, the board can find no indications, either in the decision under appeal or in the appellant's submissions, that D5 or D6 would have more features in common with present claim 1.

2.1.8 In view of the above, the board considers D1 to be the most suitable starting point for the assessment of inventive step in this case.

2.2 Distinguishing features as between claim 1 and D1

2.2.1 The closest prior art D1 discloses the following limiting features of claim 1 of the main request (as labelled by the board):

(a) an earphone (page 2, lines 7-9: "hearing-aid") for sound reproduction, comprising:

[...]

2.4 In conclusion, the main request is not allowable under Article 56 EPC.