EP 3 161 066 B1 relates to polyethylene compositions used for injection moulding.
Brief outline of the case
The opposition was rejected and the opponent appealed.
The reason for the rejection was that two resin compositions DMDA-8904 NT7 and DMDA-8907 NT7 were considered not belonging to the prior art under Art 54(2).
The board considered that, in view of G 1/23, the two compositions belonged to the prior art under Art 54(2). It followed that claim 1 as granted was lacking N over the two compositions. The amendments to claim 1 of AR I did not overcome the objection.
The patent was eventually maintained according to ARII which was deemed inventive over the two resins taken as CPA or over D6=US 7,300,988, not mentioned in the ISR established by the EPO.
The file was remitted to the OD for the adaptation of the description.
We will concentrate on AR II and the two resin compositions used as CPA.
The proprietor’s point of view on the resins as CPA
For the proprietor the knowledge of the method used to obtain the DMDA resins is essential in order to achieve a resin composition as defined in operative claim 1.
The proprietor argued that the two commercial polymer grades, DMDA-8904 and DMDA-8907, could not be reproduced by the skilled person without undue burden, due to the lack of crucial information about the catalysts and process conditions used in their manufacture.
Reverse engineering these products would not allow the skilled person to reconstruct the precise manufacturing process, as industrial polymer grades depended on complex and proprietary manufacturing methods involving specific interactions between a catalyst, process parameters, and polymerisation unit.
The proprietor further argued that the skilled person would have no motivation to modify a commercial product since the resulting product would require (re)certification.
Under these circumstances, it was not obvious for a skilled person starting from the DMDA resins as the closest prior art to obtain a composition according to claim 1 of auxiliary request II.
The opponent’s point of view on AR II
During the OP, the opponent argued that the DMDA resins were used in the same technical field as the claimed invention, making them a realistic starting point for further development.
Furthermore, the ability of the skilled person to reproduce these resins was irrelevant to the choice of the CPAt. The decisive point was whether the skilled person had access to them or could produce a resin with similar properties.
The opponent took the view that the skilled person would know how to adjust the density of the DMDA resins while maintaining the other properties, MIE, MIF and ER values, within the ranges defined in claim 1.
The board’s decision on AR II
The central point of dispute between the parties was whether a non-reproducible product can be selected as the CPA for assessing IS. In that regard, it will be assumed, for the benefit of the party arguing that the DMDA resins cannot be selected as the CPAt, that these resins could not be reproduced by a skilled person before the effective filing date of the opposed patent.
For the board, it was not in dispute that a PPU may be selected as the CPA for the assessment of IS.
This finding is supported by the case law, such as T 1464/05, Reasons 5.2.2, T 0660/16, Reasons 7.2 or T 2463/22, Reasons 6.4 to 6.6.3.
The question is, however, whether this also applies to commercial products which cannot be reproduced by the skilled person.
For the board, G 1/23 does not exclude that a non-reproducible product be selected as the CPA. Instead the specific circumstances of the case must be analysed.
It is known that the resins DMDA-8904 NT 7 and DMDA-8907 NT 7 were polyethylene compositions which could be used for injection moulding and were characterised by good impact stress crack resistance and processability.
These characteristics correspond to the technical field and the alleged advantages of the compositions claimed in the opposed patent. In the board’s view, this information makes commercial resins DMDA-8904 NT 7 and DMDA-8907 NT 7 immediately relevant for a skilled person working in the present technical field and wishing to provide alternative or even improved compositions.
Even assuming that the skilled person would not know how to reproduce these resins, the board did not consider this point to be a sufficient reason to disregard them as CPA.
First, the DMDA resins being commercially available, the skilled person could use them as such or modify these resins, within the limits of its competence, to obtain different properties. This situation essentially corresponds to the example given in G 1/23, Reasons 96.
For the board, the skilled person could have analysed the internal composition of the DMDA resins and, within certain limits, attempted to reproduce some of their properties.
In any case, there is no apparent reason why the skilled person would have considered a priori, i.e. before identifying the differences and establishing the objective technical problem solved, that any further improvement necessarily required a modification of the specific synthesis conditions employed for the preparation of the commercial product, which were not known, and excluded the product as a possible starting point on that basis.
Accordingly, even if the DMDA-8904 NT 7 and DMDA-8907 NT 7 resins were not fully reproducible, they are nevertheless a realistic starting point for further developments in the present technical field.
Contrary to the proprietor, the board did not regard the absence of the knowledge of the method used to obtain the DMDA resins as a valid criterion for not selecting them as CPA.
In this respect, the extent to which a non-reproducible product must be modified to obtain the claimed subject-matter, and the level of knowledge about that product and its manufacture required to achieve it, are not considered relevant for determining whether the product can be regarded as the CPA.
These aspects instead relate to later stages of the problem-solution approach, namely identifying the distinguishing features between the product and the claimed subject-matter and/or assessing whether the skilled person, starting from that product, would have been able to obtain the claimed one.
Under these circumstances, the board considered that commercial resins DMDA-8904 NT 7 and DMDA-8907 NT 7 can be selected as starting point for assessing IS.
For the board, the problem to be solved was, at best, the provision of an alternative composition.
Even if the selection of parameters defined in claim 1, density, MIE, MIF and ER values, is considered arbitrary, it would still be necessary to establish that the preparation of a polyethylene composition meeting those parameters was itself obvious.
The decisive issue is thus whether the skilled person, relying on the information available in the prior art and, if necessary, on CGK, would have been able to identify the measures leading to a composition that fulfils the parametric definition of claim 1, without resorting to undue experimental effort.
The exact processes by which the DMDA resins are prepared are not disclosed in the prior art and are likely to constitute confidential know-how of the manufacturer, i.e. the opponent.
Although the opponent explained in general terms which practical steps could be followed – such as the use of a Ziegler-Natta catalyst in a gas-phase fluidised-bed reactor as part of the UNIPOLTM process – it has not been shown that, by following these indications and with only routine experimentation, the skilled person would have been able to reproduce the DMDA resins or obtain materials having comparable properties.
The board accepted that a skilled person could indeed increase the density of a polyethylene, the evidence on file does not allow to conclude that a skilled person would have no difficulty in maintaining the other characteristics of the polymer. This is all the more problematic given that the ER value of DMDA resins, 0.50 for DMDA-8904 NT 7 and 0.49 for DMDA-8907 NT 7, is relatively close to the upper limit of the range defined in claim 1, 0.40 to 0.52. The opponent did not provide evidence of what a skilled person would have concretely done to adjust this parameter.
For these reasons, whether the skilled person would be able to identify the measures which would, starting from the DMDA resins, lead to a polyethylene composition that meets the parametric definition of claim 1 without having to resort to an undue amount of experimental work remains a matter of conjecture.
The board concluded that the invention defined in claim 1 of AR II has not been shown to be obvious to a person skilled in the art starting from any of the DMDA resins as the CPA.
Comments
Whilst accepting that a commercial product can be used as CPA, the board went down a different route: the obviousness hinged on whether the skilled person would have been able to reproduce the DMDA resins or obtain materials having comparable properties. This was not sufficiently demonstrated by the opponent and hence the lack of IS was not demonstrated.
The conclusion is understandable, but claiming that a commercial product is prior art under Art 54(2), and can even serve as CPA, but acknowledging IS of a claim due to the fact that the commercial product is not reproducible, is somehow contradictory and shows some problems in the reasoning of the EBA in G 1/9, at least when it comes to assessing IS.
In T 438/19, commented in the present blog, the patent leading to G 1/23 was revoked as the proprietor withdrew the approval of all requests. In the board’s communication under Art 15(1), the board argued that the product ENGAGE could be replaced by a similar product with the help of the teaching of a further document. This could be a practical route.
In T 143/24, commented in the present blog, the board held that products sold under a confidentiality agreement are not part of the prior art. Reasonable doubts are permitted whether this decision is in conformity with G 1/23, as selling products under a NDA allows to easily circumvent G 1/23.
In T 807/23, commented in the present blog, the board has apparently applied G 1/23, but sent the case back to the OD without taking any decision on the substance.
We will have to wait for more decisions to see in how far G 1/23 is actually applicable when it comes to assessing IS.
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