UK: UK Court Considers Whether Skilled Person Would "Seriously Contemplate" Working In Overlapping Ranges

Last Updated: 29 March 2017
Article by Joseph Lenthall and Stephen Hodsdon

Mewburn Ellis LLP represented Owens Corning's subsidiary, OCV Intellectual LLC ("OCV"), in its successful defence of one its glass fibre composition patents, EP(UK) 1 831 188 B, in the UK courts.  Revocation proceedings were instigated by the Jushi Group Ltd ("Jushi") in the UK Intellectual Property Enterprise Court ("IPEC"), a specialist UK IP court.  The judgment can be found on here.

The Court today handed down the decision that the patent is both novel and inventive over a US patent document, "Neely". The decision is notable for its discussion of the criterion for novelty of claims including ranges, where there is an overlap between the ranges in the claims and in the prior art.

Claim 1 of the Patent claims a glass fibre composition having a number of constituents defined by a range of weight percentages.  The claim further includes a specific weight ratio of CaO to MgO and a minimum weight percentage of Al2O3, MgO and Li2O.  Jushi relied on two specific glass fibre composition examples and two Tables containing glass fibre compositional ranges within Neely for their validity attack.

The ranges of constituents in Tables IV and VI in Neely overlap with the ranges in claim 1 of the Patent.  Jushi alleged that the skilled person would "seriously contemplate" working in the area of overlap and thus the claim of the Patent was not novel.  The "seriously contemplate" approach to novelty and overlapping ranges arises in the EPO Technical Board of Appeal ("TBA") decisions T26/85 and T666/89, and later in the UK Court in H. Lundbeck A/S v Norpharma SpA [2011] EWHC 907 (Pat).  All three decisions were discussed in the judgment.

Although Floyd J did not follow the TBA's criterion of "seriously contemplate" in Lundbeck, HHJ Hacon decided to the adopt the TBA's criterion in this case. Claim 1 of the patent includes 13 ranges.  For seven of the ranges of the patent, the corresponding Neely Table IV range is either the same as, or falls squarely within the claim 1 range.  Figures produced by both sides showed that the overlap in the remaining 6 ranges varied between around 35% and 88%.  The cumulative effect of the partially overlapping ranges means that the total area of overlap had to take into account the probability of Table IV being performed within all 13 overlapping ranges.

OCV attempted to demonstrate the total overlap by multiplying the percentages of overlap to give around 4% total overlap.  HHJ Hacon acknowledged that such a method was flawed because it assumed that the 6 overlapping ranges were entirely independent, when in fact the total of the composition weight always has to be 100%.  However, HHJ Hacon also acknowledged that the calculation of the total overlap was a complicated statistical problem.

As a result, the judge said that he was "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 ways as to arrive at something within claim 1 of the Patent." The judge went on to give specific advice to parties who wish to argue that a patent lacks novelty pursuant to the application of the "serious contemplation" criterion.  He stated that the party must provide evidence of the relevant overall area of overlap in the Grounds of Invalidity to give the court a sufficiently accurate impression of where how large the area of overlap is.  The party must also provide evidence that the skilled person would seriously contemplate implementing the prior art across the whole of the range(s) in the prior art and particularly the overlap area.

Based on the evidence, HHJ Hacon concluded that "I am not satisfied that I know the extent of the overlap between Table IV and claim 1.  Nor, more importantly, am I satisfied that it has been shown that the skilled person would seriously contemplate making fibre glass according to the teaching of Table IV within that area of overlap and thus within claim 1."

HHJ Hacon also found in favour of OCV on the other validity attacks and concluded that the patent is valid over Neely.

The team at Mewburn consisted of Dr. Joe Lenthall and Stephen Hodsdon.  They are very pleased to have helped OCV to achieve this result.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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