5.2.2 Cases in which the burden of proof was reversed
In T 792/00 the claimed invention went against prevailing technical opinion and the patent only contained a hypothetical example. The board found that if the patent contained only an example with a hypothetical experimental protocol, and if this example was to be relied on for showing sufficiency, then the burden of proving that this protocol worked in practice as stated lay with the patentee. Evidence that a variation of the protocol worked was unlikely to be enough. However, if the example contained a complete experimental protocol and the patentee affirmed that the results reported had been obtained, a board was likely to accept that the patentee had done enough to shift the burden of proof to the opponent who would then have to provide a repeat of the experiment in order to convincingly demonstrate that the protocol did not, in fact, work as stated. The findings of this decision are summarised in T 1875/19 (antibodies) as follows: in T 792/00, the deciding board held that, under the particular circumstances, the patent proprietor could only demonstrate sufficiency of disclosure if the hypothetical example was reproducible by following the experimental protocol as stated in the patent and not by using a different experimental protocol.