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

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...