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...