Smith & Nephew Plc v Convatec Technologies Inc [2015] EWCA Civ 607
Claim for a declaration of non-infringement of a patent which turned on the precision of a numerical limit. The claim was to a process which used an agent in a concentration of ‘…between 1% and 25%…’. The question was whether a process with an agent concentration of 0.77% infringed. The Court of Appeal held that it did. Consistent with the approach taken in a number of English and EPO authorities, it construed the term ‘1%’ as encompassing all concentrations which round to 1% when stated to zero decimal places i.e. all concentrations ≥ 0.5%.