Friday, 26 April 2013

T 1507/06 – Adding Zero?


This is an appeal against the rejection of an opposition.

Claim 1 of the patent as granted read:
A method of producing mineral wool, wherein fibres are produced starting from a viscous mineral melt which contains silicon and metal oxides, the fibres then being further processed to form a non-woven wool material, characterised in that added to the mineral melt is a spent aluminium silicate catalyst material which contains at least 40% by weight of aluminium oxide and at least 40% by weight of silicon oxide, as well as magnesium oxide with a proportion of up to 5% by weight and sodium and/or potassium oxide with a proportion of up to 5% by weight. (my emphasis)
The opponent argued that the components magnesium oxide and sodium and/or potassium oxide were optional because there was no lower limit for these components. They were unessential and could not establish novelty over the prior art. Thus claim 1 lacked novelty over example 2 of document D1.

In what follows the Board explains the correct interpretation of claim 1.

*** Translation of the German original ***

[1.3.1] Claim 1 of the impugned patent concerns a method of producing mineral wool, characterised in that added to the mineral melt is a spent aluminium silicate catalyst material which contains at least 40% by weight of aluminium oxide and at least 40% by weight of silicon oxide, as well as magnesium oxide with a proportion of up to 5% by weight and sodium and/or potassium oxide with a proportion of up to 5% by weight.

The Board of appeal is of the opinion that a skilled person would interpret claim 1 such that magnesium oxide and sodium and/or potassium oxide may be added to the melt either as part of the catalyst material or independently of the catalyst material. This broad interpretation follows from the fact that the conjunction “as well as” (“sowie”) is preceded by a comma, as a consequence of which the skilled person understands that a spent aluminium silicate catalyst material and magnesium oxide with a proportion of up to 5% by weight and sodium and/or potassium oxide with a proportion of up to 5% by weight are added to the melt.

Although claim 1 does not have a lower limit for the amount of magnesium oxide and sodium and/or potassium oxide, the wording of claim 1 makes it clear for the skilled person that both magnesium oxide and sodium and/or potassium oxide have to be present. As a matter of fact, claim 1 indicates that an aluminium silicate catalyst material as well as magnesium oxide and sodium and/or potassium oxide are added. This means that the addition of magnesium oxide and sodium and/or potassium oxide constitutes a process step and that it would not make technical sense if nothing was added in this process step.

Thus claim 1 establishes that magnesium oxide and sodium and/or potassium oxide have to be added. It also indicates the maximum amount, the % by weight of which have to refer to the mineral melt because the oxides are not necessarily part of the catalyst material. The fact that magnesium oxide and sodium and/or potassium oxide have to be added to the melt is also in line with the description, paragraphs [0013] and [0014] of which indicate that the catalyst material that is added according to the invention contains up to 5% by weight of magnesium oxide 5% by weight of sodium and/or potassium oxide. Magnesium oxide is added in order to reduce the crystallisation tendency whereas sodium and/or potassium oxide should be added in order to decrease the melting point. The way in which the claim is drafted does not exclude that in case of need alkali earth oxides be added, if the melt viscosity is to be reduced, as mentioned in paragraph [0010] of the patent specification.

Moreover, wording claims such that they indicate maximum amounts is standard practice in claim drafting (also see T 988/07 [2.1.2]).

Thus the Board comes to the conclusion that claim 1 is to be interpreted such that both magnesium oxide and sodium and/or potassium oxide have to be added to the mineral melt in some way.

The appeal was finally dismissed.

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

The file wrapper can be found here.

2 comments:

Unknown said...

Compare this whith T1009/12 discussed here where the fact that a lower limit of an ingredient resulted in that the presence of the ingredient was disregarded for the assessment of inventive step.

Conclustion: adding a zero amount is sufficient for establishing novelty but not for inventiveness? Or is it the word "added" vs. "comprising" that makes the difference?

Myshkin said...

I don't see a discrepancy. Not specifying a lower limit means the amount can be arbitrarily small, but more than zero. If the prior art has a zero amount, then one molecule is sufficient for establishing novelty.

Inventive step however requires as a minimum that the distinguishing ingredient achieves a technical effect over the whole claimed scope. If trace amounts of the ingredient fall within the scope of the claim, there will normally not be a technical effect, and therefore no inventive step.