Friday, January 03, 2020 T 1362/15 - No special consideration for US-style claim dependencies

This board is not a big fan of US-style claim dependencies

This is an opposition appeal for a patent that originated from a US-PCT application. In opposition, the granted claims are found not to be inventive (see point 1 and further). Auxiliary requests then run into added subject matter problems, in part, because the claims have 'US style' dependencies. The proprietor requests that questions are referred that ask whether the Board should take into account that these claims were originally drafted with a US style. The board did not consider this to be necessary though (see point 3 and further). 

Claim 10 of the main request reads as follows:

"A catalytic converter (10) comprising an outer tube (24) formed without any weld and comprising a tubular first side portion (22), a tubular second side portion (28), and a tubular intermediate portion (32) positioned between the first and second side portions (22, 28), (...) and

a tubular heat shield (18) positioned in the intermediate portion (32) around the longitudinal axis to inhibit transfer of heat from exhaust gas present in the intermediate portion (32) to the intermediate portion (32)."

Reasons for the Decision

1. Main request - Article 56 EPC

1.1 The appellant argued that the starting point E2 did not disclose the following feature of claim 10:

- a tubular heat shield (18) positioned in the intermediate portion (32) around the longitudinal axis to inhibit transfer of heat from exhaust gas present in the intermediate portion (32) to the intermediate portion (32).

1.1.1 E2, Figure 1 and column 4, lines 18 to 21, discloses a tubular shaped support ring ("Stützring 10") positioned between the ceramic bodies 3 and 3' around the longitudinal axis as defined in claim 10. This ring is made of metal or ceramics, as disclosed in column 3, lines 19 to 23.

1.1.2 The appellant argued that there was no indication that the support ring 10 of E2 had any of the properties required for this purpose. However, the patent also does not disclose any particular physical feature of this heat shield consisting of an inner tube 40 (such as a specific material or thermal conductivity) that could lead the skilled person to establish a difference between the inner tube 40 of the patent and the support ring 10 of E2. In the absence of any discernible difference, the support ring 10 in E2 thus corresponds to an inner tube 40 and is therefore also a heat shield, since it poses a further barrier against contact with the hot exhaust gas, which inhibits, at least to some extent, heat transfer from the inside space of the intermediate portion to the wall of the intermediate portion.

1.1.3 The appellant's argument that the support ring 10 in E2 could be made of steel or ceramics and that the thermal conductivity of these materials was either notoriously high or not disclosed, does not alter the Board's conclusion. As already stated above, whilst it is true that E2 does not disclose the thermal conductivity of the steel and ceramic materials used in the support ring, neither does the patent, let alone the claim, specify any material or material property necessary for the tube 40 to qualify as a heat shield.

1.1.4 The appellant argued further that the heat shielding function in E2 was carried out by the mat 2 and not by the ring 10. The embodiment of Figure 1 in E2 comprises a mat 2 and a ring 10 in the same fashion as paragraph [0013] and Figure 1 of the patent together disclose that the heat shield 18 comprises an inner tube 40 and, optionally, an additional insulation layer 12. Both arrangements are analogous. If the inner tube 40 in this embodiment of the patent is considered a heat shield according to the invention, there is no reason to assume differently for the ring 10 in E2, since no structural differences have been defined.

1.1.5 As the appellant also argued, E2 comprised embodiments with a thin foil replacing the support ring 10, and in these embodiments only the mat 2 provided a heat shielding function. However, the heat shielding function of the mat 2 and of the support ring 10 in E2 are not mutually exclusive and the support ring 10 provides an additional heat shield in the same way that the heat shield 18 of the patent disclosed in paragraph [0013] may comprise an optional insulation layer 42 in addition to tube 40.

1.1.6 Thus, the support ring 10 in E2 corresponds to the tubular heat shield as defined in claim 1.

1.2 It is undisputed between the parties that the feature

- outer tube (24) formed without any weld

was not unambiguously disclosed in E2 and that all the remaining features of claim 10 were disclosed in E2. The Board also sees no reason to find otherwise, in particular since although no weld is shown or described, this does not mean that no weld is present.

1.3 The appellant argued that an outer tube formed without any weld was necessarily seamless, and thus resulted in a single piece which then provided a continuous circular inner surface that centered the heat shield perfectly. The Board however does not find this argument correct. Other manufacturing techniques which do not resort to welding, such as tying, crimping or gluing, do not result in a seamless continuous circular inner surface made of a single piece, yet still fall within the claim as the claim only excludes welded tubes and a tubular shape does not necessarily need to have a circular cross-section (see e.g. E4, Figure 4 and column 1, lines 29-55, disclosing a tube with an oval cross-section). The Board can see no technical effect provided by excluding welding from the possible tube manufacturing methods.

The objective technical problem to be solved when starting from E2 as the closest prior art can thus be formulated as being to provide an alternative joining technique for the formation of the outer tube.

1.4 E2 does not disclose any specific information regarding the formation of the metal tube. However, the Board finds that many suitable techniques for forming a tube from a single piece or from two shells, besides welding, are well known in general mechanics to the skilled person, such as extrusion, gluing, crimping or tying. The skilled person would, when looking for an alternative technique, simply select another suitable one from their knowledge of known possibilities, such as tying the two shells together e.g. by circular metal clamps. They would thus arrive at the subject-matter of claim 10 in an obvious manner.

1.4.1 The appellant argued that at the priority date of the patent no other method was known to the skilled person in this specific technical field besides welding, such that the skilled person would not look for any other solution. The Board however does not accept this. There is no feature, implicit or explicit, in the claim that would limit the tube formation technique to any specific method from the joining techniques known to the skilled person well before the priority date from general mechanical production techniques. For example, there is no technical limitation in the claim that would make it unsuitable for the skilled person to tie two shells together and apply a sealant between them.

The appellant's argument that such methods would not withstand high temperatures and seal properly, does not persuade the Board. In the absence of any evidence to support the appellant's argument, the Board finds that the formation and joining techniques known to the skilled person allow for shells to be made, tied and sealed with enough precision and such that they can withstand the temperatures in catalytic converters.

1.4.2 The argument that the skilled person would not arrive at a seamless continuous central cylindrical housing portion when starting from the housing shape of E2, since the conical end side portions would then have to be formed separately, is not found convincing by the Board. As discussed above, the wording of claim 1 simply excludes welding but does not define a seamless housing, i.e. other joining techniques besides extrusion for joining two shells are possible, even those with seams. The longitudinal section in Figure 1 of E2 does not show any discontinuity, but the skilled person knows that the discontinuity may lie in another plane and would recognize in an obvious manner that the shape of the tube in E2 would be obtainable even if it were formed, for example, by tying two separate shells together.

1.4.3 The appellant further argued that many techniques, such as tying, did not allow for a reduction of the diameter of the side portions. However, apparatus claim 10 does not define the specific sequence or the method used to create this reduced diameter. Thus, when tying the two shells, each portion of the shell may possibly already be preformed to the various specific diameters. Thus, the appellant's argument does not alter the Board's conclusion.

1.5 For the above reasons, the subject-matter of claim 10 of the main request is obvious to a skilled person when starting from E2 and given the technical problem to be solved, simply when considering the common knowledge of the skilled person. The subject-matter of claim 1 therefore does not involve an inventive step (Article 56 EPC). The main request is thus not allowable.

(...)

3. Request for referral of two questions to the Enlarged Board of Appeal

3.1 The appellant requested the referral of two questions to the Enlarged Board of Appeal under Article 112(1)(a) EPC (see point VIII. above)

3.2 It is first noted that Article 112(1) EPC provides for the Enlarged Board of Appeal only to have questions referred to it by a Board of Appeal in order to ensure uniform application of the law, or if a point of law of fundamental importance arises. Concerning the issues at hand, the Enlarged Board of Appeal has already clearly defined the general principles which govern the requirements of Article 123(2) EPC inter alia in G 2/98 and G 2/10, i.e. that the skilled person must be able to derive the claimed subject-matter directly and unambiguously, using common general knowledge, and seen objectively and relative to the date of filing, from the original application as a whole.

3.3 Secondly, the referred question must not have a merely theoretical significance for the proceedings in the case to be decided, which would for example be the case if the referring Board were to reach the same decision regardless of the answer to the referred question (see G 3/98, item 62, and G 2/99, item 83).

3.4 Regarding the "U.S. style" claim dependency, the Board notes that there is no actual limitation regarding the possible combinations of features in the claims of a U.S. application. 35 U.S.C 112 allows multiple dependent claims to be drafted and states only that a multiple dependent claim shall not serve as a basis for any other multiple dependent claim. Contrary to the argument of the appellant, this is however not an absolute prohibition or even an insurmountable limitation, as it could be overcome, merely for example, by the use of several independent claims in the same category and/or by redrafting of the dependent claims accordingly.

3.5 The Board also notes that in the present case the relevant dependent claims do not refer back to the independent claim separately in the way that "U.S. style" dependency is defined in question 1. For example, originally filed claims 16 and 17 refer back to originally filed dependent claim 15.

3.6 The further argument from the appellant that such an approach (the use of multiple dependent claims) would involve high cost, also does not constitute a (legal) limitation to the rights of the party. Thus, the Board cannot recognize any dependency "style" or any other reason that could change its way of assessing the compliance with Article 123(2) EPC referred to above under point 3.2.

3.7 The appellant further argued that, in cases where the amended claim was a combination of features containing features from originally filed dependent claims that did not respect the original dependency, the existence of an embodiment in the disclosure containing all the combined features (albeit with even more features) should be enough to fulfill the requirement of Article 123(2) EPC and this was a relevant point of law in which Boards diverged considerably. The appellant pointed to an alleged contradiction between T 2619/11 and T 1414/11.

3.7.1 The Board is not persuaded by this argument and finds that the criteria stated in point 3.2 are the necessary and sufficient criteria to assess the requirement of Article 123(2) EPC. The claimed subject-matter, i.e. the claimed combination of features, must be clearly and unambiguously derivable from the whole content of the application as originally filed. If the combination of originally filed claims alone does not fulfill this criteria, it must be established whether this combination of features is derivable from any other part of the application as filed. This criteria is valid, irrespective of the particular dependency structure of the originally filed claims.

3.7.2 In T 1414/11 (see Reasons 2.2.2 and 2.2.3), the Board found that the first sentence of the fourth paragraph of page 5 in the description directly and unambiguously enabled the skilled person reading the application to derive that the binding agent with graphite particles was applicable to all the carbon and graphite layers of the invention, including the layer materials of dependent claims 2 and 3 and thus provided the basis for the combination of features of dependent claims 2 and 3 with the amended claim 1.

3.7.3 In T 2619/11 (see Reasons 2.5 to 2.9), the Board found that what was directly and unambiguously disclosed for the skilled person reading the application was that the tapered portion of the tube with the features of Figure 3 could extend over "the entire length" of the tube, which was the same as "the whole length" defined in the original claims, and that "substantially the whole length" was a more specific embodiment of "at least a substantial portion" and not an alternative thereto. The Board thus came to the conclusion that the Examining Division had made a mistake by focusing disproportionately on the claim structure of the original application and not on what the skilled person would clearly and unambiguously derive from the application as a whole (see also T 1629/15, Reasons 2.10.2).

3.7.4 The Board thus concludes that both decisions rely on the (same) criteria mentioned above in point 3.2 and do not contradict each other.

3.8 Thus, the Board came to the conclusion that a referral to the Enlarged Board of Appeal was not justified. The Board thus refused the request for referral.

4. Auxiliary requests 2-4 - Article 123(2) EPC

4.1 Claim 10 of auxiliary requests 2 to 4 defines inter alia that the catalytic converter comprises an oxygen sensor secured to the intermediate position. This feature was defined in the originally filed claim 14 which depended directly from independent claim 13 and was not linked to any other claim depending from independent claim 13, such as claims 15 and 17, which the appellant also provided as a basis for the subject-matter of claim 10.

4.2 The appellant argued that although no combination of dependent claims provided the specific combination of features of claim 10 of any of auxiliary requests 2 to 4, the embodiment of Figures 5 to 7 comprised all the features of claim 10 of auxiliary requests 2 to 4 and thus provided a basis for the respective combination of features.

The Board does not accept this. The description relating to the embodiment of Figures 5 to 7 on page 5, line 18, to page 6, line 4, does not disclose an oxygen sensor. Only Figures 5 to 7 disclose an oxygen sensor. The oxygen sensor and its positioning disclosed in these Figures is however more specific than the one defined generally in claim 10 of auxiliary requests 2 to 4. For example, it is secured to the intermediate portion through a sensor mount 36 that is not defined in claim 10 of any of auxiliary requests 2 to 4.

4.3 The appellant argued that the claimed oxygen sensor was not defined in further detail because it was not relevant for the invention, but the Board does not find this argument convincing. Figures 5-7 disclose an oxygen sensor with certain specific features and in the whole of the disclosure it is nowhere stated that such an oxygen sensor or any part of it is less relevant or can for example be left out. Thus, in the absence of any information to the contrary, the skilled person would only directly and unambiguously derive an oxygen sensor with more specific features (such as the sensor mount mentioned above) than defined in claim 10 of auxiliary requests 2 to 4, when using Figures 5 to 7 as the basis.

4.4 For the reasons stated above, the subject-matter of claim 10 of auxiliary requests 2, 3 and 4 extends beyond the content of the application as originally filed and the requirement of Article 123(2) EPC is thus not fulfilled. Consequently, auxiliary requests 2, 3 and 4 are not allowable.

Order

For these reasons it is decided that:

1. The request for referral of questions to the Enlarged Board of Appeal is refused.

2. The appeal is dismissed.

This decision T 1362/15 (pdf) has European Case Law Identifier: ECLI:EP:BA:2019:T136215.20191008. The file wrapper can be found here. Image "flag-heart-love-united-states" by  Alexey Hulsov (Alex80) obtained under the Pixabay License