Apimed Medical Honey Ltd v Brightwake Ltd (t/a Advancis Medical)

For obviousness, the court must identify the actual differences between the prior art and the inventive concept, then ask, without hindsight, whether those differences were obvious to the skilled person. A known dressing is not the relevant difference where, on the proper construction of the claim, it cannot perform the claimed gelling function. The critical step may instead be dispensing with a separate dressing and using a gelling agent to increase honey’s viscosity sufficiently for it to form a flexible sheet or pliable putty. An attack based on common general knowledge requires particular caution. It must identify the starting point and precise difference; a bare assertion that honey could be made thicker is insufficient.

Apimed owned a European patent for medical dressings comprising gelled honey. It alleged that Brightwake’s Algivon dressing infringed. Brightwake denied infringement and counterclaimed for revocation for lack of novelty and obviousness.

The Patents County Court held that the patent was not infringed and was invalid for obviousness, while rejecting the novelty challenge. Apimed appealed the finding of invalidity. Following settlement, the non-infringement issue was not pursued. The Court of Appeal therefore considered whether the patent was obvious over the Molan paper or the common general knowledge, including whether the relevant difference was merely the substitution of alginate dressings for gauze, or the use of a gelling agent to form the honey into a dressing without a separate dressing material.

Lord Justice Kitchin gave the leading judgment. Lord Justice Etherton and Lord Justice Toulson agreed.

1. Construction and skilled person. The unchallenged construction of claim 1 meant that calcium alginate and sodium-calcium alginate felt dressings did not constitute natural based gelling agents. Applying honey to such a dressing therefore did not produce the claimed composition. The skilled person was properly identified by reference to the practical work addressed by the patent. The court also rejected the argument that the skilled person needed a particular level of interest in honey. The prior art was to be read properly and with interest, through the eyes of the skilled person, applying Catnic Components Ltd v Hill Smith Ltd [1982] RPC 183, Schlumberger Holdings Ltd v Electromagnetic Geoservices AS [2010] EWCA Civ 819 and Asahi Medical Co Ltd v Macopharma (UK) Ltd [2002] EWCA Civ 466.
2. Molan paper. Applying the structured approach in Pozzoli SpA v BDMO SA [2007] EWCA Civ 588, the judge had identified the wrong difference between the prior art and the inventive concept. The real difference was not replacing gauze with a known alginate dressing. It was discarding the separate dressing and using a gelling agent, such as particulate sodium alginate, to increase honey’s viscosity sufficiently to form a flexible sheet or pliable putty. The Molan paper taught liquefying or spreading honey on a dressing pad, or squeezing it into a deep wound. It gave no teaching that the critical claimed step was obvious.
3. Common general knowledge. The judge’s brief reasoning did not identify the starting point, the precise difference, or why the skilled person would make the required combination without hindsight. Merely making honey thicker did not address the claim’s requirement for a composition capable of being rolled into a sheet or used as a putty without a separate dressing. The caution required for common-general-knowledge attacks was applied in accordance with Abbott Laboratories Ltd v Evysio Medical Devices UCL [2008] EWHC 800 (Pat).
4. Disposition. The appellate restraint applicable to findings of obviousness did not prevent intervention where the judge had made errors of principle, as recognised in Biogen Inc v Medeva plc [1997] RPC 1 and Lundbeck A/S v Generics (UK) Ltd [2008] EWCA Civ 311. The appeal was allowed. The Comptroller’s new technical argument based on Kaltostat was not admitted because it had not been raised below, lacked evidential development and could not properly be resolved on appeal.

• Patents County Court: His Honour Judge Fysh QC held on 14 January 2011 that the patent was not infringed and was invalid for obviousness, while rejecting the allegation of lack of novelty.
• Court of Appeal (Civil Division): The appeal against invalidity was allowed. The non-infringement finding was not pursued following settlement. [2012] EWCA Civ 5