For the purpose of assessing novelty, the party alleging that the inevitable outcome of a prior art disclosure is in contradiction with the explicit disclosure of the cited prior art has not only the burden of reproducing the earlier disclosure in such a way as to demonstrate that the alleged inevitable outcome has occurred, but also the burden of proving convincingly that if any significant deviation from the conditions specified in the earlier disclosure are not material to the outcome (T 204/00; see also T 396/89).
In T 713/01 the appellant denied the existence of an "enabling" disclosure in D2 with regard to the preparation of polymers in the presence of a solubilised lithium pyrrolidide initiator by reference to T 124/87 (OJ 1989, 491) and T 206/83 (OJ 1987, 5). According to this case law, the criterion for a prior art disclosure to be novelty-destroying is that the claimed subject-matter should be directly and unequivocally inferred from an enabling disclosure in it. In the case at issue, the board held that the only difference between D2 and the claim wording, i.e. the presence or not of a solubilising agent as part of the lithium pyrrolidide initiator, did not qualify as a distinguishing feature of the claimed product because that "product-by-process" feature was not detectable on the product by a reliably distinguishing property. In this context, the board added that in proceedings before the examining division the burden of proof for an allegedly distinguishing "product-by-process" feature lay with the applicant (see further T 205/83, OJ 1985, 363 and T 279/84).