T 1497/08 – Tell Me All

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

Claim 1 of the main request before the Board read:

A process for producing a fried flour-based product, comprising the steps of:

(a) preparing a dough comprising flour, water and an added lipolytic enzyme which has phospholipase activity in the range of 0.5- 45 kLEU per kg flour,

(b) holding the dough during or after mixing, and

(c) frying the dough to obtain the fried product.

In the proceedings before the Board, the question of clarity proved decisive:

[2.1] During the opposition proceedings, the parameter “phospholipase activity in the range of 0.5-45 kLEU per kg flour” was inserted into claim 1 of the main request. The claim does not specify how this phospholipase activity has to be measured.

According to […] the description of the opposed patent, the phospholipase activity “may be determined by the plate assay in WO 02103805 (PCT/DK 01/00472) or by an assay WO 2000/32758, e.g. the PHLU, LEU, monolayer or plate assay 1 or 2”. A specific method for determining phospholipase activity is given in paragraphs [0042] and [0043] of the opposed patent.

It has to be examined whether, under these circumstances, the insertion of the phospholipase activity into claim 1 meets the requirements of A 84, in particular in view of the fact that no information is contained in the claim as to how to determine this activity.

[2.2] According to A 84, the claims define the matter for which protection is sought. This implies that the claims must be clear in themselves when being read by the competent technical expert exercising normal skills, without the need to resort to information derived from the description of the patent.

As is set out in numerous decisions (e.g. T 1156/01 [2.2-3], T 412/02 [5.6-9], T 908/04 [3.1-8] and T 555/05 [3.2.7-10]), this implies that the method for measuring the parameter (or at least a reference thereto) must appear completely in the claim itself, if the invention is characterised by a parameter.

[2.3] As set out above, in the present case, no such method (or reference thereto) is contained in claim 1 of the main request.

[2.4] In this situation, the requirements of A 84 would still be met if it could be shown that

(i) knowing which method to employ belongs to the skilled person’s common general knowledge, or

(ii) all the methodologies known in the relevant technical field for determining this parameter yield the same result within the appropriate limit of measurement accuracy (see e.g. decision T 1156/01 [2.3]).

[2.4.1] As regards point (i), no evidence has been provided by the [patent proprietor] that it is indeed part of the skilled person’s common general knowledge to know which method to employ to measure phospholipase activity. In fact, the opposed patent itself acknowledges […] that different methods may be used to determine phospholipase activity. This is confirmed by D13, D35, D36 as well as by […] the opposed patent, where various measurement methods are described that differ inter alia in terms of pH and temperature. More particularly, pH and temperature vary as follows:

• pH 5 and 37ºC (“PLU” method described [in] D13),
• pH 7 and 30ºC (“PHLU” method described [in] D13 and LEU method in […] the opposed patent),
• pH 7 and 37ºC (point 2.3 [in] D36) and
• pH 8 and 40ºC ([…] D35).

The skilled person reading claim 1 would not know which of these methods to apply, and in particular which pH and temperature to use when determining the phospholipase activity required by this claim.

The [patent proprietor] argued in this context that the [opponent] itself did not specify the method for determining phospholipase activity when referring to this activity in its own patent applications D37-D39. In the [patent proprietor’s] view this proved that the skilled person, on the basis of common general knowledge, would know which measurement method to apply.

However, three single patent applications cannot in general constitute proof of what the skilled person’s common general knowledge is. Moreover, D37-D39 focus on amylases rather than phospholipases, and no reference to phospholipase activity is made in any of the claims of these documents. It is thus not surprising that no measurement method for determining the phospholipase activity is given in these documents. In view of this, it remains unclear to the board how the omission of the method for determining phospholipase activity in D37-D39 can constitute proof that the skilled person, on the basis of common general knowledge, would know which method to apply and in particular which pH and temperature to use when determining phospholipase activity. The [patent proprietor’s] argument therefore must fail.

[2.4.2] As regards point (ii), namely the question whether all measurement methods yield the same value for the phospholipase activity, it follows from table 4 of D13 that the phospholipase activity strongly depends on the pH employed during the measurement. More particularly, by varying the pH from 5 to 8, which is the range of pH values used in D13, D35, D36 and the opposed patent […], phospholipase activity determined for one and the same enzyme changes by 375%. Equally, by varying temperature from 30ºC to 40ºC, which is the range of temperatures used in D13, D35, D36 and the opposed patent […], phospholipase activity determined for one and the same enzyme changes by 18% ([…] D13).

The same can be observed when pH and temperature are changed simultaneously. More particularly, for one and the same enzyme, phospholipase activity is

• 1454/mg-1458 LEU/mg (opposed patent […]) when measured at pH 7 and 30ºC,
• 1540 LEU/mg when measured at a pH of 8 and a temperature of 40ºC ([…] D35), or
• 225 LEU/mg when measured at pH 7 and 37ºC ([…] D13, “PHLU” is equivalent to LEU […]).

[2.5] In summary, the skilled person reading claim 1 would not know which method to apply for the determination of the phospholipase activity and when trying different measurement methods, he would obtain different activities for one and the same enzyme. The activity range required by claim 1 is therefore unclear, which implies that claim 1 of the main request does not meet the requirements of A 84.

[2.6] The [patent proprietor] argued that claim 1 met the requirements of A 84 as a measurement method was given in […] the opposed patent. The [patent proprietor] referred in this context to decision T 94/82.

However, this decision nowhere contains a general statement that it is sufficient for a measurement method to be contained in the description when a claim refers to a parameter. In fact, the decision refers to the specific case in which the parameter is “usual in the art” and “can conveniently and reliably be obtained in following the instructions given in the description and in accordance with the German standard DIN 53840 mentioned therein” (point [2.3] of the reasons). This clearly differs from the present case, in which the only specific method mentioned in the description does not constitute a generally recognised German or other national standard and it is even explicitly acknowledged in the description that various methods can be applied […].

Accordingly, the decision referred to by the [patent proprietor] and the reference in […] the opposed patent to a specific measurement method cannot invalidate the above finding that claim 1 lacks clarity.

I for one do not approve of this approach because, as I have already said somewhere, this will only lead to clumsy claims, without any real benefit for whomsoever. The reader of a patent can be expected to look for measuring methods etc. in the description. But this decision clearly indicates the direction into which we are moving.

To read the whole decision, click here. The file wrapper can be found here.