1.13.2 Schematic drawings

In T 748/91 the board, agreeing with the appellant, held that schematic drawings depicted all the essential features. The board reached the conclusion that size ratios could be inferred even from a schematic drawing as long as the delineation provided the relevant skilled person with discernible and reproducible technical teaching (with reference to T 451/88). In the case at issue the description provided the skilled person a sufficient teaching for an unambiguous interpretation of the drawing.

In T 497/97 the board noted that, since drawings were often approximate and therefore unreliable, they could only be used in interpreting amended claims if the description did not contain a more precise indication of what was meant.

Likewise, in T 906/97 the board held that the parent application as filed failed to disclose unambiguously the position of a door. The only indication of this position could be found in some figures, and in the board's view there was no suggestion whatsoever in the description itself that this detail of the schematic representation was actually meant to correspond to a technical feature of the apparatus shown in the figures, rather than being merely an expression of the draughtsman's artistic freedom.

In T 1148/12 the board distinguished the case at hand from the one in T 748/91. In the case at issue in T 1148/12, the schematic nature of the figures did not allow the skilled person to clearly and unmistakably derive the feature in question (parallel arrangement of electrodes), nor did the description of the original application allow him to clearly and unmistakably derive anything related to the function of the purported parallel arrangement.

In T 614/12 the board found that the drawing did not show any measurements or scale or give any other indication that it was an exact engineering drawing reproducing the construction elements to scale. It was thus no more than a schematic illustration of the kind commonly found in patent documentation. The imprecision of such an illustration made it impossible to measure angle sizes.

In T 398/00 the appellant sought to derive a feature (concerning the positioning of an engine) from the drawings. Referring to T 169/83 (OJ 1985, 193) the board explained that what would be required was that the person skilled in the art would clearly unmistakeably recognise from the drawings, in the context of the description as a whole, that locating the engine according to this feature was the deliberate result of technical considerations directed to the solution of the technical problem involved. Given in particular the schematic nature of the illustration of the engine, this was however not the case. Cited in T 886/15.