T 428/09 – On Purpose

This is a revocation appeal.

Claim 1 of the main request before the Board (and claim 1 as granted) read (in English translation):

Process for recovering clear solutions containing cell contents from biological samples in a high throughput process, comprising the steps of

(a) preparing a plurality of protein-containing solutions which contain insoluble ingredients in separate chambers of a multi-chamber filtration unit,

(b) removing insoluble ingredients by filtering the solutions through the multi-chamber filtration unit with the application of a pressure differential, cross contamination of adjacent chambers being prevented by the addition of an antifoam to the cell lysates and/or by the use of a transfer unit between the outlet end of the multichamber filtration unit and the inlet end of the collecting containers, and

(c) collecting the individual filtrates separately in collecting containers.

In what follows, the Board examines the novelty of this claim.

*** Translation of the German original ***

[1] Claim 1 of the main request is directed at a process for recovering clear solutions containing cell contents from biological samples in a high throughput process, comprising three steps (a), (b), and (c). Step (b) mentions the addition of an antifoam as one alternative for preventing the cross contamination of adjacent chambers. According to claim 2 the antifoam is selected from primary, secondary or tertiary C1-6 alcohols. The specification mentions ethanol as preferred antifoam […].

[2] In the impugned decision the Opposition Division (OD) had come to the conclusion that e.g. Example 11 of document D14 deleted the novelty of the subject-matter of claim 1 […].

[3] Document D14 concerns a process for isolating cell contents such as nucleic acids from natural sources by removing the digested natural sources such as cells or cell debris by filtration […]. In a preferred embodiment of the process according to the invention, multiple samples are processed simultaneously and passed through appropriate devices advantageously adapted to microtitration systems. […] Figure 7 shows a preferred embodiment of the device according to the invention, which may be present in the form of microtitration strips. In Figures 8 and 9 corresponding configurations, each having different adsorption materials, are described […]. It is also disclosed […] that up to 96 samples may be processed at the same time when the design of the filtration device according to the invention is in microtiter format.

[4] Example 11 of document D14 discloses […] a process for the preparation of genomic DNA from liver tissue that is performed in a multi-chamber filtration unit […]. First the liver tissue is comminuted and the cells are lysed at 50°C for 2 hours by addition of proteinase K. Then ethanol is added and the filtration device is attached on top of a vacuum chamber, and the cell lysate is sucked through the device. The filter cake, together with cell fragments, is discarded and the filtrate is sucked through the silica gel extraction column to achieve adsorption of DNA. Subsequently the extraction column is washed to remove RNA and proteins. Finally, the DNA is eluted and is collected in tubes. Thus the Board is of the opinion that document D14 discloses a process for recovering liver tissue solutions containing DNA in a high throughput process, comprising the three process steps of the process according to claim 1 of the impugned patent.

[5] The [patent proprietor] points out that document D14 does not disclose a high throughput process or the preparation of a plurality of protein-containing solutions because Example 11 only discloses the treatment of a single sample and because there was no figure corresponding to figure 9.

[6] The Board cannot endorse this argument. It is true that none of the devices shown in the figures of document D14 is marked as “figure 9”. However, both the device shown on sheet 7/8 and the one shown on sheet 8/8 are marked as “figure 8”. As the devices shown on sheet 7/8 and 8/8 are different and as the description of document D14 discloses more than one that there is a device according to figure 8 and a device according to figure 9 […] the skilled person would have understood that one of the two devices marked as figure 8 was indeed the device according to figure 9. According to […] D14, the devices shown in figures 8 and 9 differ in respect of the adsorption materials. As […] the device shown in figure 9 has both an anion exchanger layer (10) and a silica gel layer (11), there is no doubt for the skilled person that the device shown on sheet 8/8 of D14, which contains both layers, corresponds to figure 9. This understanding is confirmed by the European patent specification (D1) corresponding to document D14, where the corresponding figure is marked as figure 9 […].

[7] The device according to figure 9 of document D14 comprises eight columns in which the cell lysates are processed in parallel […]. Thus the Board is of the opinion that Example 11 discloses both a high throughput process and the preparation of a plurality of solutions according to step (a).

[8] According to the established case law of the Boards of appeal, it is not justified, when the novelty of a claim is to be assessed, to read into the claims features that are only disclosed in the description (Case Law, 6^th edition, 2010, II.B.5). Thus the parallel treatment of at least 24, preferably at least 48 and most preferably 96 samples or more […], which is disclosed in the description of the impugned patent, does not limit claim 1. Moreover, the general teaching of document D14 is clearly directed at the parallel treatment of several samples in devices that are adapted to microtitration systems […]. According to the established case law of the Boards of appeal the technical teaching of examples can be combined with the teaching offered elsewhere in the same document (such as in the description of a patent document) provided that the example under consideration is in line with the general technical teaching that is disclosed in the document (Case Law, 6^th edition, I.C.2.2). Thus the skilled person would have directly and unambiguously derived from the general description of document D14 in connection with the process disclosed in Example 11 and the device shown in sheet 8/8 that the process may be performed using up to 96 filtration units in parallel.

[9] Claim 1 only requires the preparation of a plurality of protein-containing solutions and does not specify that they have to be different. Thus the parallel treatment of one sample disclosed in document D14 is covered by claim 1. Moreover, the treatment of aliquots is explicitly mentioned in the impugned patent […].

[10] The [patent proprietor] also submitted that Example 11 did not disclose step (a) of the process according to claim 1 because the treatment with proteinase K led to proteins being “completely digested”.

[11] The Board is of the opinion that the solutions prepared in Example 11 of document D4, which are obtained by lysing rat liver tissue, contain proteins, not least because of the presence of proteinase K (a protein) that is used for cell lysis. Moreover, claim 1 only requires the solutions prepared in step (a) to contain protein. Claim 1 does not exclude the degradation (Abbau) of the proteins in a subsequent step because the claim is directed at a process comprising the steps (a), (b), and (c).

[12] The argument of the [patent proprietor] according to which document D14 does not contain any reference to a clear solution is not persuasive either. The Board notes that the impugned patent uses the expressions “clear solution” and “filtrate” synonymously for referring to a solution which is substantially free from insoluble matter such as cell debris for example […]. Example 11 of document D14 explicitly discloses the removal of cell debris by filtration and the preparation of a DNA containing filtrate and, thus, the recovery of a clear solution containing cell contents.

[13] Thus the only difference with respect to the process according to document D14 is that according to step (b) of claim 1, the addition of ethanol has the purpose of preventing the cross contamination of adjacent chambers, whereas in the process according to document D14, ethanol is added in order to adjust the sample to the adsorption conditions on glass.

[14] According to the established case law of the Boards of appeal, the technical features of a process claim are the physical steps defining the process (cf. G 6/88 [2.5]). The physical step of adding ethanol in step (b) of claim 1 of the impugned patent is identical to the physical step of adding ethanol in Example 11 of document D14. When [ethanol is added], the purpose of preventing cross contamination of adjacent chambers, which is based on the antifoam effect of ethanol, is obtained regardless of whether the addition of ethanol to the cell lysates was performed in view of this or a different purpose. Thus the Board is of the opinion that the purpose for which ethanol is added in step (b) of the process according to claim 1 cannot constitute a feature that establishes novelty.

[15] The [patent proprietor] points out that according to decision T 848/93 the use feature in step (b) of claim 1 should indeed be considered as a functional feature of the process that could establish novelty.

[16] In decision T 848/93 the claim under consideration was directed at a process for remelting galvanic layers on printed circuit boards. It was the use of the process (remelting instead of vapour phase soldering) that was different from the prior art. The competent Board came to the conclusion that in line with decisions G 2/88 and G 6/88 of the Enlarged Board the process feature of remelting galvanic layers constituted a functional technical feature establishing novelty (see [3.1-4] of the Reasons).

[17] However, the Board is of the opinion that the considerations of T 848/93 are not applicable to the present case because what is being discussed is not whether the use of the process  can establish novelty but whether the use of a single process step [can have this effect].

[18] Moreover, according to more recent case law of the Boards of appeal, the indication of purpose in a process claim directed at the manufacture of a product does not constitute a limiting feature within the meaning of decisions G 2/88 or G 6/88 (see Case law, 6^th edition, I.C.5.3.[1] e and f, as well as, e.g. T 1049/99 [8.4.4-8.5]; T 1343/04 [2]; T 1179/07 [2.1.3]; T 304/08 [3.3.2-3]).

[19] For the reasons given above, the Board comes to the conclusion that claim 1 does not comply with the requirements of A 54. The impugned decision is not to be criticised in this respect.

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