Saturday, 23 June 2012

T 1644/07 – A Problematic Extraction

In T 201/83, it was said that “[a]n amendment of a concentration range in a claim for a mixture, such as an alloy, is allowable on the basis of a particular value described in a specific example, provided the skilled man could have readily recognised this value as not so closely associated with the other features of the example as to determine the effect of that embodiment of the invention as a whole in a unique manner and to a significant degree”. The present decision gives an example where this condition was not fulfilled.

All the parties appealed against the maintenance of the opposed patent in amended form.

The decision contains an interesting discussion on whether the main request before the Board complied with the requirements of A 123(2). Claim 1 of this request read (in English translation; my emphasis):
Pulverulent polymerisate which has been post-crosslinked at the surface, which absorbs water or aqueous fluids and which is composed of polymerised, possibly pre-crosslinked monomers containing partially neutralised carboxyl groups, characterised in that the pulverulent polymerisate has been reacted following the post-crosslinking with an Aluminium sulphate of [sic], wherein the concentration of the Aluminium sulphate in the solution lies between 25.86 and 80 wt.%, calculated in anhydrous form (wasserfrei berechnet).
*** Translation of the German original ***

[2] The issue that has been debated in view of A 123(2) concerns the basis for the boundaries of the numerical range of the feature “wherein the concentration of the Aluminium sulphate in the solution lies between 25.86 and 80 wt.%, calculated in anhydrous form” in the characterising part of claim 1.

[2.1] The question to be answered in this context is whether the numerical value calculated from the indications given in Example 20 can be generalised and applied as the lower limit for the concentration range over the whole breadth of the subject-matter of the claim. As a matter of fact, the Examples all dealt with the treatment of some specific polymerisates based on acrylic acid.

[2.2] It is true that the salt concentration of the salt solution used for the post-treatment of the polymerisate is an important parameter, but is only meaningful when seen together with the quantity of solution in relation to the polymerisate. Moreover, the nature of the polymerisate, the nature of the post-crosslinking and its degree of crosslinking as well as the portion of fine particles (Feinteilchen)  and the absorption speed (Aufnahmegeschwindigkeit) of the water, which is related to the latter, play an essential role.

For the sake of completeness, [the Board] refers to the statement in the paragraph bridging pages 2 and 3, according to which the abrasion of polymerisate particles, i.e. fine dust, in particular impairs the ability of a swollen absorber gel to transport further liquid (so-called “gel blocking”). The Board is of the opinion that this holds true in a general way for all such polymerisates, all the more as no explanations contradicting this [view] have been put forth. These statements can be summarised [by saying] that in such a system there is a great number of interactions as a consequence of which the generalisation of such a particular value for the salt concentration over the whole breath of the claims is inadmissible.

[2.3] In other words, it cannot be asserted that the numerical value “25.68 wt.%” in Example 20 is independent of the other boundary conditions mentioned in this Example. As a consequence, the numerical value does not fulfil the criteria that apply to the admissibility of the generalisation of this value and its use as boundary in the independent claims that extend far beyond the Example. Concerning these criteria, [the Board] refers to decision T 201/83.

Therefore, the lower boundary of 25.68 wt.% for the concentration range introduced into claims 1 and 5 has to be considered not to be directly and unambiguously disclosed in the original documents.

[2.4] For this reason alone, the main request […] is not allowable because it violates the requirements of A 123(2) as a result of the new definition of the concentration range. As a consequence, it is not necessary to deal with the arguments concerning the upper boundary of the range.

[2.5] Therefore, the main request is dismissed.

Should you wish to download the whole decision (in German), just click here.

The file wrapper can be found here.