(1) For sufficiency of disclosure (Articles 100(b) and 83 EPC), the Board has to be satisfied firstly that the patent specification certainly puts the skilled person in possession of at least one way of putting the claimed invention into practice, and secondly that the skilled person can put the invention into practice over the whole scope of the claim. If the Board is not satisfied on the first point that one way exists, the second point need not be considered (Point 2).

(2) If for an invention which goes against prevailing technical opinion the patentee has failed to give even a single reproducible example, sufficiency of disclosure cannot be acknowledged. It would amount to undue burden for the cautious and conservative skilled person to have to do research of his own to establish whether the invention can be put into practice in some circumstances, not specifically described in the patent, when prevailing technical opinion suggests the outcome will be failure (Points 3 to 5).

(3) If the patent contains only an example with a hypothetical experimental protocol, if this example is to be relied on for showing sufficiency, then the burden of proof lies on the patentee to show that in practice this protocol works as stated. Evidence that a variation of the protocol works is unlikely to be enough (Points 9 to 11).