T 110/07 – One Way Only

Back to basics!

One of the opponents filed an appeal against the decision of the Opposition Division (OD) to maintain the opposed patent in amended form.

The Board did not agree with the way in which the OD had validated the priority claim:

[2.1] The patent in suit claims the priority dates of 14 March 1997 (P1) and of 23 July 1997 (P2). The earlier priority document P1 discloses, as a thickness for the sodium ion diffusion barrier layer (SIDB), the ranges of 2 to 50 nm […] and 2 to 18 nm […]. Furthermore, P1 discloses in the examples individual values of SnO2 CVD-deposited SIDB layer thickness of 101 nm, about 100 nm, 434 nm […], and of 50 nm for SnO2 layers obtained by spray pyrolysis […]. Thus, P1 fails to disclose the range in the claim feature “sodium diffusion barrier layer … having a thickness of at least 10 nm” […]. This was not disputed by the respondent. The question is therefore whether a PASC layer thickness of “at least 10 nm” may be derived from P1.

[2.2] Opinion G 2/98 [ 8.4] – to which the OD referred in the contested decision […] – states that

“[t]he requirement for claiming priority of “the same invention”, referred to in A 87(1), means that priority of a previous application in respect of a claim in a European patent application in accordance with A 88 is to be acknowledged only if the skilled person can derive the subject-matter of the claim directly and unambiguously, using common general knowledge, from the previous application as a whole.”

For the board, neither the claimed lower limit of 10 nm nor the open-ended range of ≥ 10 nm is directly and unambiguously derivable from P1, so that the earlier priority date is not valid.

[2.3] The OD came to a different conclusion, upon applying a “novelty test” based on the concept of overlapping ranges. The board considers the application of this “novelty test” as inappropriate in view of G 2/98 itself, because in the present case there is no overlap, but rather a generalization of ranges. It is true that G 2/98 [8.4] states that “priority claims should not be acknowledged if the selection inventions in question are considered “novel” according to these criteria” (i.e. the criteria applied by the EPO with a view to assessing novelty of selection inventions over the prior art). However, it does not automatically follow from the said statement that priority claims should be acknowledged if the selection inventions in question are considered not “novel”. (In this context, attention is drawn to decisions T 1233/05 [4.4], T 230/07 ([headnote, 4.1.6] and T 1130/09 [3.2] according to which the demonstration of a technical effect over a sub-range is not decisive for acknowledging novelty. A sub-range must be novel per se.)

[2.4] The feature in question relating to the thickness of the SIDB layer is however literally disclosed in P2 […] so that the patent enjoys priority rights of 23 July 1997.

Should you wish to download the whole decision, just click here.

The file wrapper can be found here.

NB: This appeal was won by fellow blogger Laurent Teyssèdre. Congrats!