Court of Appeal grapples with novelty of overlapping ranges in Jushi v OCV

Is it novel to select a numeric range overlapping with a previously disclosed numeric range? A recent Court of Appeal judgment clarifies the UK approach to the patentability of numeric ranges.

According to UK case law and the Technical Boards of Appeal (TBA) of the European Patent Office (EPO), for a range overlapping with a known range to be novel, the prior art must at least not disclose specific values within the overlapping range. This is the principle that a generic disclosure is not novelty destroying for specific examples covered by the generic. 

An example outside the overlap does not destroy the novelty of an overlapping range

The TBA have established further criteria for an overlapping range to be novel. The claimed range must also, for example, have a technical effect. These criteria can seem addressed to the question of inventiveness as opposed to novelty. For this reason, the UK courts have previously been reluctant to adopt the TBA approach. The recent decision by the Court of Appeal has now firmly incorporated part of the EPO's approach into UK case law.

The Patent

The case concerned whether OVC’s EP(UK) patent for glass fibres (EP 1831118) was novel and inventive in view of a single piece of prior art. The Claimant, a Chinese fibreglass manufacturer, admitted threatened infringement and brought an action of revocation against OVC's patent.

The patent relates to glass reinforcement strands that are both cheap and easy to work with. Claim 1 specifies a glass strand composed of a number of constituents at percentage weights within specified ranges. 

Fibreglass Kats

The prior art US 4199364, “Neely”, was cited by the patent itself. Neely discloses glass compositions composed of the same compounds as that of the patent, at the same or overlapping percentage weights. The point of contention in both the IPEC and Court of Appeal was whether ranges in the prior art that overlapped with those of the invention were novelty destroying. 

Novelty of overlapping ranges – EPO approach

The EPO treats overlapping ranges as equivalent to sub-ranges selected from a broader range of the prior art (T 666/89). In T 279/89 the TBA defined the criteria by which overlapping ranges are assessed for novelty. The overlapping range must be narrower and sufficiently removed from the end-points of the known range. The selection must also have a technical effect, or in other words, be another invention. This approach has been confirmed in subsequent decisions by the TBA, and is currently supported by the EPO Guidelines for Examination.

T 230/07 contradicts the approach of T 279/89, and states that the present or absence of a technical effect of a selection should not be taken into account when assessing novelty. According to the Board, such an assessment relates to the inventiveness, not novelty, of the invention. However, this approach is not currently supported by the guidelines.

According to the TBA, an overlapping range is also disclosed by the prior art if a skilled person would be able and reasonably expected to operate within the overlap (T 26/85). In other words, an overlapping range is not novel if a skilled person would have “seriously contemplated” operating within it.  The TBA has emphasised that this criteria is different to the test for determining inventive step (T 666/89). In particular, the test for inventive step asks whether a skilled person would have tried to bridge the technical gap between the prior art and the claimed range, with a reasonable expectation of success. The test for inventive step does not apply in the case of overlapping ranges because there is no technical gap to bridge.

Novelty of overlapping ranges – UK approach

The UK courts have previously expressed dissatisfaction with the EPO’s approach to the novelty of overlapping ranges. In Lundbeck v Infosint [2011] EWHC 907 (Pat) (IPKat post here), Mr Justice Floyd observed in obiter that, according to the principles of novelty adopted in the UK courts, an overlapping range is novel solely on the basis that it is a narrower selection. This appeared to contradict the position of the TBA, which requires the additional criteria that the overlapping range would not be seriously contemplated in view of the prior art range, and that selection of the range should have a technical effect.

Jushi v OCV – The IPEC decision 

At first instance, His Honour Judge Hacon reasoned that the “seriously contemplated” test of the TBA was in fact necessary to determine the novelty of overlapping ranges.  Hacon HHJ reasoned that under Floyd LJ's suggested approach, ranges with 99% overlap with a known range would be novel.  Hacon HHJ argued that the TBA devised the “seriously contemplated” test to exclude such ranges.

This Kat is not convinced by this reading of the motives of the TBA. An overlapping range is treated as equivalent to a sub-range by the EPO, and must therefore be sufficiently narrow compared to the known range (T 0666/89). According to the EPO Guidelines for Examination, the meaning of the term “narrow” is to be assessed on a case-by-case basis. Thus, one might expect a range with 99% overlap to lack novelty because it lacks narrowness, without the need to assess whether the range would be seriously contemplated. The EPO’s criteria instead seem to be directed at removing arbitrary selections from patentability, and subsets of the prior art ranges that would have been readily used by the skilled person.

The Jushi v OCV dispute was complicated by the multiple overlapping ranges specified in the claim. What was the overall percentage overlap over the entire claim with the prior art composition?  

The Claimant’s expert put the total overlap at 3.9%, by multiplying the individual percentages. The Defendant’s expert argued that this approach was flawed, because it presumed that the individual overlapping ranges were entirely independent: “Even at the simplest level, an increase in one constituent could exert a downward pressure on the percentage of another, because the total must always come to 100%”. Hacon HHJ was unable to determine the percentage overlap from this testimony.

Overall percentage overlap?

Hacon HHJ further remained unsure whether a skilled person would seriously contemplate the overlapping range:

“I was in the end left with no useful idea, not even a vague one, as how likely it was that the skilled person would seriously contemplate juggling all 13 ranges in such a way as to arrive at something within claim 1 of the Patent”

Hacon HHJ thus ruled that claim 1 was novel, given that he determined the burden of proof to be on the side of the party alleging invalidity.

As an aside, this Kat’s own statistical expert advises her that the 3.9% figure for the overlapping ranges will be very close to the true value. This is because there is only a single constraint (i.e on the sum of the constituents). The true figure isn't going to be lower than 3% or higher than 5%. The statistics required to calculate the precise value are not as simple as multiplying the numbers together, but the value can easily be obtained by writing a straightforward computer program.

The Court of Appeal

The Court of Appeal did not resolve the question of the amount of overlap, but came to a finding of novelty for different reasons.

Applying the TBA approach, Lord Justice Floyd argued that a skilled person would expect small changes in percentages to have large non-linear effects on the properties of glass fibres. A skilled person would therefore not understand Neely as suggesting that one may indiscriminately choose any combination of values from the disclosed ranges. This analysis appears in line with the TBA approach, for which teaching away in the prior art conferred novelty to an overlapping range, because it demonstrates that a skilled person would not have seriously contemplated operating within the overlap (T 0026/85). 

Lord Justice Floyd did not, however, follow the TBA approach of additionally assessing whether the overlapping range has a technical effect. This was perhaps because the technical effect was assumed to be clear (given that the patent directly compared the invention with the glass fibres disclosed by Neely). However, there was perhaps scope for argument that the proposed technical effect was not enabled across the entire scope of the claim, and so could not confer an inventive step, at least according to a European approach to inventiveness. 

Inventive step

The claims were also deemed inventive by both the IPEC and the Court of Appeal. In the Court of Appeal, Lord Justice Floyd employed similar reasoning as that used for novelty. Particularly, he reasoned that a skilled person would not be motivated to modify the ranges of Neely, given expert testimony that a skilled person would expect even small changes to the individual constituents to have a disproportionately large effect on the properties of the glass.  

Commentary

The IPEC and Court of Appeal judgment clarify the UK court’s position on overlapping ranges. The UK’s approach is now in line with that of the TBA, at least with regards to the test for the disclosure of an overlapping range in the prior art. To be novel, an overlapping range should not have been seriously contemplated by a skilled person in view of the prior art. However, neither court commented on whether the EPO’s requirement that an overlapping range should have a technical effect is consistent with the UK novelty requirement established by Lord Hoffmann in Synthon BV v Smithkline Beecham plc [2005] UKHL 59. Given that the technical effect criteria is now the well-established approach of the TBA, it is hoped the UK courts will follow suit. But will this sit comfortably with the UK court's understanding of novelty? Jushi v OCV thus provides some clarity on the UK approach to the novelty overlapping ranges, but more is still needed.

Author: Rose Hughes