MÖLNLYCKE HEALTH CARE AB v BSN MEDICAL LIMITED

Patent claims are construed purposively in their technical and descriptive context. A product claim directed to a coating concerns the resulting physical relationship, not the process used to create it. Where a claim requires gel-coated end parts of foam holes, the gel must coat the inside walls of those holes; contact merely at the edge is insufficient. A material is a gel if it has the required cross-linked structure and extractable liquid, together with sufficient softness and adhesion to perform the invention. Novelty requires a clear and unambiguous disclosure or direction in the prior art. Obviousness is assessed on all the circumstances using the structured approach. A patent is not insufficient merely because its technical contribution lies in a novel product configuration rather than specified numerical properties.

Mölnlycke sued BSN for infringement of European patent (UK) No 0 855 921 concerning wound dressings comprising absorbent foam coated with hydrophobic, skin-adhering gel. BSN denied infringement and challenged validity for lack of novelty, obviousness and insufficiency.

The alleged products were the Cutimed Siltec range. The central construction issue was whether the claim required the gel to enter and coat the inside walls of holes in the foam, or whether contact at or near the hole edge was sufficient. The court also had to determine whether the products contained gel and whether the patent was invalid over Lang 1 or insufficient for extending beyond stated adhesion and softness values.

1. Construction. Applying the purposive approach in Kirin Amgen v TKT [2005] RPC 9 and the guidance approved in Virgin Atlantic v Premium Aircraft [2009] EWCA Civ 1062; [2010] FSR 10, “coated” referred to the physical result and did not require a particular manufacturing process. “Skin-adhering” imposed no specific numerical adhesion threshold. A secondary dressing could assist in forming a seal. “Gel” was context-dependent, but required a cross-linked structure, extractable liquid and sufficient softness and adhesion to perform as described.
2. Feature (f) required the gel to coat the inside walls of the holes at their skin-facing ends. The patent’s teaching about thin gel layers, material savings, prevention of foam contact and prevention of reflux supported that construction. Gel merely abutting the edge of a hole was insufficient. Claim 2 did not alter that conclusion.
3. Infringement. The Cutimed products satisfied the coating, skin-adhering and gel requirements. The experimental evidence did not establish that the gel coated the inside walls of the relevant holes. Isolated contact points and mechanical contact from lamination could not substitute for that requirement. There was therefore no infringement.
4. Validity. Applying Synthon v SmithKlineBeecham [2006] RPC 10, Lang 1 did not clearly and unambiguously disclose or direct the skilled person to make a dressing with a hydrophobic gel layer. The claim was novel. Applying the structured approach in Pozzoli v BDMO [2007] EWCA Civ 588; [2007] FSR 37, BSN had not shown that the claimed combination was obvious over Lang 1.
5. The insufficiency objection failed. The technical contribution lay in the novel structure and its components, so the reasoning in Pharmacia v Merck [2002] RPC 41 did not apply.

The patent was valid, but no accused product infringed it.