T 0987/17 - Burden of proof technical effect on patentee

 Key points

• The OD found claim 1 to be obvious in view of D3. The patentee submits comparative results with the Statement of grounds allegedly showing an improvement.
• “As D3 was not acknowledged in the application from which the patent at issue was granted, this prior art document was not considered when formulating the technical problem to be solved originally. ”
• “Thus, the technical problem invoked by the appellant [patentee] in its statement and at the oral proceedings has been formulated for the first time in appeal proceedings. ”
• “The board notes that it is established case law (see e.g. T 1188/00 of 30 April 2003) that a formulation of a more ambitious technical problem first alleged in the opposition/appeal proceedings cannot be used to substantiate inventive step unless it is plausibly demonstrated that the alleged improved effect could be achieved across the whole scope of the claim. The burden of proof however lies with the proprietor in this respect.”
• After considering the facts and evidence, “ the board has strong reservations that the problem is effectively solved across the breadth of claim 1 at issue”. In the end the claims are found to be obvious.

T 0987/17 - 

https://www.epo.org/law-practice/case-law-appeals/recent/t170987eu1.html

2.3 Technical problem

In its grounds of appeal, the patent proprietor formulated the technical problem to be solved over D3 as "to provide multilayer tubes having improved mechanical properties and improved (inter-layer) adhesion" in particular in view of the results in the comparative tests D9.

At the oral proceedings, on the basis of the results shown in D9, the appellant invoked only "good (inter layer) adhesion" in addition to "improved mechanical properties".

2.4 Solution

As a solution to the problem underlying the alleged invention, the patent as granted provides the multilayer tube according to claim 1, which is in particular characterised by the presence of

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2.5 Success of the solution

2.5.1 As D3 was not acknowledged in the application from which the patent at issue was granted, this prior art document was not considered when formulating the technical problem to be solved originally. As apparent from [0003] and [0006] of the patent, as well as from the comparison in the original examples over a tube made of two layers of PA-11, the technical problem was simply formulated as to provide a multilayer tube having good mechanical properties such as pressure resistance, vibration resistance, and flexibility, with good impact behaviour when cold and at high temperature, as well as good resistance to engine lubrication oils and fuels. There is however no mention of an improvement, let alone of an improved adhesion.

Thus, the technical problem invoked by the appellant in its statement and at the oral proceedings has been formulated for the first time in appeal proceedings.

2.5.2 The board notes that it is established case law (see e.g. T 1188/00 of 30 April 2003) that a formulation of a more ambitious technical problem first alleged in the opposition/appeal proceedings cannot be used to substantiate inventive step unless it is plausibly demonstrated that the alleged improved effect could be achieved across the whole scope of the claim. The burden of proof however lies with the proprietor in this respect.

2.5.3 Therefore, in the case at issue, the board has strong reservations that the problem is effectively solved across the breadth of claim 1 at issue, because:

- a technical problem based on an improvement in adhesion may not be allowed, as having not been formulated originally;

- the comparative tests in the patent are not made over a tube according to D3, but over a two-layers tube of only PA-11;

- the closest embodiment of claim 6 of D3 is open as to the nature of the polyamide and neither requires the presence of e.g. elastomers such as the EPRm used in D9, nor of a tie layer;

- although D9 shows an improvement for the particular tube J, having PA6,10 and polyolefin as the inner layer material, there are no comparative example in D9 with polyamides as such, i.e. without elastomers, let alone with the co-polyamides disclosed under "polyamides" in D3;

- comparative test D8 (filed in opposition with letter of 26 May 2015) does not concern PA6,6 but PA6, mentioned not only in [0022] of D3 but also in [0126]. Moreover, the tubes tested do not differ only in the kind of PA but also in their material formulation, such as the different amount of elastomer, plasticiser and stabiliser, and the results show that the presence of polyolefin or of a further polyamide such as PA11 greatly influences the mechanical properties such as the crash test at low temperature (shock), in so far as a PA-6,10* has a result in such a test which is slightly lower than the threshold for acceptance (47 vs 50, compared to 20 for the PA-6,10 with elastomer), although using only 10% of PA11. Hence, as already expressed in the communication in preparation for oral proceedings, it has not been plausibly shown that the claimed multilayer tube has improved mechanical properties over the multilayer hoses of claims 1 and 6 of D3 across the whole breadth of claim 1 at issue.

2.5.4 Nevertheless the board assumes arguendo, in favour of the appellant, that in view of D3 the formulation of the technical problem to be solved can be seen - as invoked by the appellant at the oral proceedings - in the provision of "a multilayer tube inter alia (see [0003] of the patent) exhibiting improved impact behaviour when cold and good (inter layer) adhesion upon coextrusion".

2.5.5 The board also assumes in favour of the appellant that the single improvement shown in D9 is transposable and thus achieved across the entire breadth of claim 1 at issue, so that the technical problem invoked by the appellant would be effectively solved.

2.6 Obviousness of the proposed solution

2.6.1 It remains to be assessed whether the skilled person starting from D3 and facing the above problem would have been motivated to implement the generic closest embodiment disclosed in D3, claims 1 and 6, over the whole teaching of D3 and thereby would have arrived in an obvious way at a multilayer tube as defined in claim 1 at issue.

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2.6.8 Therefore, the skilled person working in the technical field of the patent, starting from D3 and considering the disclosure of its paragraph [0021], would have used polyamides such as PA6,12 for implementing the inner layer of the multilayer tube according to claims 1 and 6 of D3 in the expectation of achieving improved shock resistance and good inter-layer adhesion with PA11 or PA12 over the polyamides such as PA6,6 encompassed in [0021] of D3, in view of his background knowledge on the general properties of the polyamides for multilayer tubes for transferring fluids as apparent from D4 and D10. Thereby it would have arrived in an obvious way at a multilayer tube with an outer layer of PA11 or PA12 and an intermediate layer made of e.g. PA6,12, i.e. a polyamide A1 as defined in claim 1 at issue.

2.6.9 The board thus concludes that the subject-matter of claim 1 as granted was obvious over D3 taken as the closest prior art (Article 56 EPC).

2.7 Since the ground of opposition under Article 100(a) EPC (lack of an inventive step) prejudices the maintenance of the patent as granted, the (sole) request on file of the appellant cannot be allowed.

Order

For these reasons it is decided that:

The appeal is dismissed.