The relevant part of Claim 1 of the patent in suit reads as follows:
“1. Use of at least one of melamine cyanurate, melamine-phosphate, melamine-pyrophosphate or melamine-polyphosphate as an adhesion enhancer in an elevator load bearing member (26), a passenger conveyor drive member (56), or a passenger conveyor handrail (48)(…).”
With reference to G 2/88, the Opposition Division (OD) held that claim 1 was functionally limited by the adhesion enhancing effect and considered that none of the grounds raised (Art. 100 (c) and (a) in combination with Art. 54 and 56 EPC) prejudiced maintenance of the patent.
In its appeal, the opponent (appellant) raised a new ground of opposition under Art. 100 (b) EPC and argued that the adhesion enhancer effect was not sufficiently disclosed. Concerning inventive step, the appellant argued that, as a consequence of the lack of proof, the effect could not be considered as a limiting functional feature and was therefore, obvious in view of the cited prior art.
The respondent objected against the introduction of the fresh opposition ground under Art. 100 (b) EPC and consequently, the Board had no power to examine sufficiency of disclosure.
With respect to inventive step, the claim would be considered to involve an inventive step, on the proviso that “as an adhesion enhancer” were acknowledged to be a limiting functional feature.
The Board assessed the conditions imposed by G2/88:
Condition (i) was undisputed and therefore met. The decision thus, hinged on the interpretation of “described in the patent”.
According to the Board:
“There is, however, no pointer in the Enlarged Board's considerations suggesting that an assessment of the plausibility or credibility of the actual achievement of the claimed technical effect on the basis of the patent's description would be required (…) when examining whether a claimed new technical effect should be understood as a limiting functional technical feature of a use claim.”
Thus, the Board concluded that “described in the patent” relates to whether the skilled person can recognize what technical effect is underling the new purpose claimed.
The Board considered that “adhesion enhancer” is described in the patent and thus, the condition (ii) of G 2/88 (see above) is met. Consequently, the attaining of the technical effect was considered as a limiting technical functional feature of claim 1 that cannot be ignored when examining inventive step.
Since the adhesion enhancer effect of the melamine derivatives neither belongs to common general knowledge nor is it disclosed in the cited prior art, the subject-matter of claim 1 involves an inventive step.
The Board further concluded that:
“Whether the effect is plausibly described, rather than merely described, is not relevant to the present decision since this concerns, in the case of an effect defined in the claim itself, the opposition ground under Article 100(b) EPC. Only where the effect is not defined in the claim, would the question then arise of whether such effect needs to be taken into account when deciding on inventive step.”
The appeal was dismissed.