Patents: Convatec Ltd. v Smith & Nephew Healthcare Ltd
In Convatec Ltd. and others v Smith & Nephew Healthcare Ltd and Others [2011] EWHC 2039 (Pat) (27 July 2011), His Honour Judge Birss QC, sitting as a judge of the High Court, tried a claim for patent infringement and a counterclaim for revocation of the patent in suit on the grounds of anticipation, obviousness and insufficiency.
The invention for which the patent was granted was a moist wound dressing. The patent specification explained that most dressings consisted of materials that tended to absorb puss and other body fluids produced by a wound known as exudate. Such absorption tended to dry and thereby stick to the wound thus impeding healing. The invention was a gel that kept the wound moist while absorbing exudate.
The relevant claims were as follows: "Claim 1: A wound dressing comprising a blend of discrete modified cellulose gel forming fibres with at least one other type of discrete gel forming fibres. Claim 3: A wound dressing as claimed in any preceding cla...