UK – Mölnlycke Health Care v BSN Medical

Posted: November 13th, 2012

Mölnlycke Health Care AB and Mölnlycke Health Care Limited v BSN Medical Limited and BSN Medical GMBH, 9 November 2012, Case No. HC09C03755, Neutral Citation Number: [2012] EWHC 3157

Mölnlycke Health Care alleged that BSN Medical’s “Cutimed Siltec” range of layered wound dressings infringed its European Patent (UK) No 0855921, which claimed a wound dressing comprising a layer of “holey” form coated with a layer of skin-adhering hydrophobic gel (e.g. silicone gel) wherein the walls of the holes in the foam were coated with gel at the ends which were proximal to the wearer’s skin.  BSN claimed that the patent was invalid for want of novelty, inventive step and sufficiency.

Mr Justice Floyd held that the patent was valid, but not infringed by the BSN products.

In construing the patent, Mr Justice Floyd confirmed that in the context of a product claim, the court was concerned with the end result and not with the means by which that result was achieved. Thus the requirement in claim 1 that the foam be “coated” with hydrophobic gel would be understood by the skilled person to mean that the foam and gel must be in intimate contact with one another; investigation into how that contact was achieved was irrelevant for the purposes of the claim.

The assessment of infringement turned on: (i) whether the silicone layer of the BSN products constituted a “gel”; and (ii) whether the silicone in the BSN product coated the walls of the holes in the foam.


BSN performed experiments in an attempt to show that their silicone was not a gel as required by the patent.  However, the judge held that, on the correct construction of the term “gel”, what mattered was whether the material was sufficiently gel-like to perform in accordance with the invention. It was impossible to say that the BSN silicone was not sufficient of a gel for the purposes of the patent.

The two sides approached the second issue using different experimental techniques: Mölnlycke used X-ray tomography whilst BSN used scanning electron microscopy. In the end both sets of experiments revealed a product in which the silicone layer did not coat the walls of the holes in the foam. Thus, the experimental evidence did not support a finding of infringement. Of interest is the Judge’s commendation of the parties’ use of a grid to indicate regions on the micrographs, which helped to ensure that everyone was looking at the same place on the photograph.

Turning to validity, the Judge held that the patent was neither anticipated by, nor obvious over, a US patent for a three layered wound dressing. In considering the scope of the common general knowledge, Floyd J did not accept that that an entire chapter from a standard reference text would have been part of the common general knowledge. Had it been so, Floyd J would have expected to see other documents produced to evidence that state of knowledge.

Finally, the Judge held that the patent was not insufficient. BSN had alleged that insufficiency was demonstrated by the fact that Mölnlycke had to rely on tests which were not specified in the patent in order to demonstrate adhesion and softness. Thus, the case was analogous to Pharmacia v Merck [2002] RPC 41 in which the Court of Appeal held that it was necessary to test whether the extent of the monopoly claimed exceeded the technical contribution by adopting the criteria which were used in the specification to explain that technical contribution. Mr Justice Floyd was not persuaded that the cases were analogous since, in contrast to the situation in Pharmacia, Mölnlycke’s invention did not lie only in the identification of a particular degree of skin adherence and softness. Thus, the patent was not insufficient.

Read the judgment (in English) here.

Head note: Gina Lodge and Graham Burnett-Hall

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