T 0261/15 - Novelty of steel alloys

Key points

• Claim 1 is for a stail rail, wherein the steel consists of the the elements C, Si, Mn, V, N, P, S, H, Cr, Al and O each with a range for the amount, the balance being Fe and unavoidable impurities.
• D1, D5, D9, and D8 disclose steel with (some of) these elements, but with different (but overlapping) ranges.
• Is claim 1 novel? The Board: " Thus, in the case of an alloy composition, a disclosure of a combination of the different alloying elements within the claimed ranges is necessary for a finding of lack of novelty." 
• The Board: " The criterion (c) [of T 279/89, "the selected area should not provide an arbitrary specimen from the prior art, i.e. not a mere embodiment of the prior description, but another invention (purposive selection)."]  by contrast goes beyond the comparison of the invention defined in the claims with the disclosure of the prior art, because it considers the presence of an effect of the claimed invention. Whether the claimed selection is purposive or not is thus, in the view of the present Board, more a question of inventive step than of novelty. As pointed out by the respondent, this view is also taken in the majority of the more recent jurisprudence (see for instance T 1233/05, T 230/07 or T 1948/10)." 
• "The appellant [opponent]  attempted to find a teaching in D1 leading towards the claimed composition. Depending on the alloying element, the appellant considered for some elements the middle of the composition range disclosed in D1, whereas for other elements the limit values of the broad or preferred ranges taught in this document were used. In respect of the limit values the appellant further argued that these values were explicitly disclosed and that in order to recognise novelty of a sub-range selected from a broader numerical range of the prior art the selected sub-range had inter alia to be sufficiently far removed from the end-points of the known range. The approach taken by the appellant is an exercise in cherry-picking within the disclosure of D1, which creates a novel combination of features that is not disclosed in D1" 
• " In the view of this Board, the limit values of a known range, although explicitly disclosed, are not be treated in the same way as the examples. The person skilled in the art would not, in the absence of further teaching in this direction, necessarily contemplate working in the region of the end-points of the prior art range, which are normally not representative of the gist of the prior art teaching." 
• Compare recent decision [2018] EWCA Civ 1416, discussed here on IPKat. 
• Generally, the reason why for metal alloys and steel compositions, granted claims always use " consisting of .... the balance being Fe and unavoidable impurities" (or similar phrasing) was discussed here and boils down to established EPO practice described in the article of Mr.  Spiekermann in Mitt. 1993 (XP002152326)

EPO T 0261/15 -  link

2. Novelty

2.1 Claim 1 is directed to a pearlitic steel rail which is defined by its composition.

Novelty objections have been raised in view of each of D1, D5, D9 and D8. The composition of claim 1 and the broad compositions disclosed in these documents are compared in the following table (in wt%):

2.2 Novelty of a composition or a numerical domain has to be assessed, like the novelty of any other subject-matter, by comparing the invention as defined in the claim with the disclosure of the prior art.

2.2.1 For an invention to lack novelty, its subject-matter must be clearly and directly derivable from the prior art. A claimed subject-matter would lack novelty only if a "clear and unmistakable teaching" of a combination of the claimed features could be found in a prior art disclosure (Case Law of the Boards of Appeal of the European Patent Office, 8th edition 2016, I.C.4. and I.C.4.2).

Thus, in the case of an alloy composition, a disclosure of a combination of the different alloying elements within the claimed ranges is necessary for a finding of lack of novelty.

2.2.2 Alloy compositions often present a situation wherein the state of the art includes documents containing technical teachings described in general terms (the broadest composition ranges); these teachings in turn subsume a number of more specialised technical teachings (e.g. the specific embodiments). In assessing the novelty of subject-matter that can be subsumed under a general term in the state of the art, the question arises whether the general term makes the claimed matter fully or partially accessible to the public. In other words, it has to be established whether the general term used in the citation discloses the subject-matter defined by the special term in the claim. The prior-art disclosure needs to be identified particularly carefully in such cases (Case Law of the Boards of Appeal of the European Patent Office, 8th edition 2016, I.C.6.1).

According to decision T 279/89 and numerous decision following it (see Case Law of the Boards of Appeal of the European Patent Office, 8th edition 2016, I.C.6.3.1) a selection of a sub-range of numerical values from a broader range is new when each of the following criteria is satisfied:

(a) the selected sub-range should be narrow;

(b) the selected sub-range should be sufficiently far removed from the known range illustrated by means of examples;

(c) the selected area should not provide an arbitrary specimen from the prior art, i.e. not a mere embodiment of the prior description, but another invention (purposive selection).

The first two criteria (a) and (b) compare the invention as defined in the claims with the disclosure of the prior art, as is proper to the examination of novelty. They take into account that a disclosure of a prior art document disclosing a numerical range with some examples of embodiments within it is not limited to the specific examples disclosed in this document. Rather it should be assessed, on the basis of the teaching of the whole document, in which region of the broad composition the person skilled in the art would seriously contemplate working.

The criterion (c) by contrast goes beyond the comparison of the invention defined in the claims with the disclosure of the prior art, because it considers the presence of an effect of the claimed invention. Whether the claimed selection is purposive or not is thus, in the view of the present Board, more a question of inventive step than of novelty. As pointed out by the respondent, this view is also taken in the majority of the more recent jurisprudence (see for instance T 1233/05, T 230/07 or T 1948/10).

2.3 As can be seen in the table above, the claimed composition overlaps with the generic composition of the pearlitic rail disclosed by D1 (claims 1 and 6).

2.3.1 Since the different alloying elements interact with each other to form precipitates and solid solutions their content ranges are not to be considered in isolation but in combination. Hence, the range of overlap is narrow in respect of the composition of D1 (see for instance contents of C, Si, Mn, S and V).

Moreover, none of the several inventive examples of D1 exhibits a composition in accordance with present claim 1. In particular, no example has a V content as claimed, the disclosed contents being all below the claimed lower limit. The example with the highest V content is example 2-10 of table 3, with 0.04% of V and with C, Mn and S also not in accordance with claim 1. Moreover, the S more preferred content of D1 (page 5, line 15) is lower than the claimed range. Therefore, the examples and the teaching of D1 do not lead the person skilled in the art to seriously contemplate working in the claimed composition.

2.3.2 The appellant [opponent] attempted to find a teaching in D1 leading towards the claimed composition. Depending on the alloying element, the appellant considered for some elements the middle of the composition range disclosed in D1, whereas for other elements the limit values of the broad or preferred ranges taught in this document were used. In respect of the limit values the appellant further argued that these values were explicitly disclosed and that in order to recognise novelty of a sub-range selected from a broader numerical range of the prior art the selected sub-range had inter alia to be sufficiently far removed from the end-points of the known range.

The approach taken by the appellant is an exercise in cherry-picking within the disclosure of D1, which creates a novel combination of features that is not disclosed in D1, for instance by considering the preferred ranges for some elements (such as C) while disregarding them for other elements (such as S for which the preferred range does not overlap with the presently claimed range).

The same applies to the limit values known from the prior art which, albeit being explicitly disclosed values, cannot be combined with each other at whim as the case to be made may require.

Finally, in respect of the argument according to which a selected sub-range has inter alia to be sufficiently far removed from the end-points of the known range the Board points to that it is not aware of any jurisprudence stating this condition in such a general way. It is true that the Guidelines for Examination in the European Patent Office, G.VI.8, recite under point (ii)(b) this criterion as a condition for acknowledging novelty of a numerical selection. However, neither of decisions T 198/84 and T 279/89 which are cited in this passage of the Guidelines stipulates this condition. In the view of this Board, the limit values of a known range, although explicitly disclosed, are not be treated in the same way as the examples. The person skilled in the art would not, in the absence of further teaching in this direction, necessarily contemplate working in the region of the end-points of the prior art range, which are normally not representative of the gist of the prior art teaching.

As already explained above, in the present case D1 does not provide any teaching which would lead the person skilled in the art to seriously contemplate working in the claimed composition.

2.3.3 Even if one were to consider for the sake of argument the presence of "purposeful selection" as a pre-condition for acknowledging novelty this would not change the above finding in view of D1, since the claimed invention provides improved RCF (rolling contact fatigue) and wear resistance (Figures 1 and 2).

2.3.4 Therefore, D1 is not novelty-destroying.