Select Healthcare (UK) Ltd v Cromptons Healthcare Ltd & Anor

Patent claims must be construed purposively, by asking what the skilled person would understand the language to mean in the context of the specification. A claim requiring a pimpled finish is not satisfied by dimples produced by pin bonding or embossing. A coating may exist even where the low-friction material migrates to the surface from a mixture; the manufacturing method is immaterial where the claim is directed to a product. An invention is obvious where the skilled person would plainly consider the claimed difference as an available way of solving the relevant problem. The specification must enable performance across the claim’s scope without prolonged research, but routine trials and ordinary manufacturing adjustments are permissible.

The claimant, an alleged exclusive licensee, brought a patent infringement claim concerning a disposable patient slide sheet. The first defendant denied infringement and counterclaimed for revocation of the patent for obviousness, insufficiency and added matter. The disputed claim covered a nonwoven patient slide sheet with a pimpled, low-friction coated surface which could be folded for use. The central issues were the construction of “pimpled finish” and “coated”, whether the defendant’s Poly-Glide product infringed, and whether the patent was valid.

1. Construction. Claim 1 required a nonwoven material with an array of protuberances rising above the common surface and promoting friction reduction. The term “pimpled finish” did not require particular geometric shapes or protuberances visible to the unaided eye, but it intentionally excluded finishes produced by pin bonding and similar embossing processes. “Coated” meant a covering layer of low-friction material. It did not require a distinct manufacturing step applying that material on top of the surface.
2. Infringement. Poly-Glide’s appearance resulted from pin bonding and embossing, producing dimples rather than pimples. It therefore lacked the required pimpled finish. The additive, probably erucamide, migrated to the polyethylene surface and formed a thin low-friction coat. That element of the claim was satisfied, but the product did not infringe because the pimpled-finish requirement was absent.
3. Obviousness. Applying the structured approach in Pozzoli v BDMO [2007] EWCA Civ 588, the difference between the prior art and the inventive concept was the pimpled finish. The skilled person knew that separating smooth contacting surfaces could reduce friction and that protrusions or pimples could achieve that separation. The experts accepted that this was an obvious approach and straightforward to implement. Claim 1 was therefore obvious over Berge and Berge 2.
4. Insufficiency and added matter. The skilled person could implement the claimed invention using routine trials and manufacturing adjustments, so the insufficiency allegation failed. Applying the comparison required by Bonzel v Intervention [1991] RPC 553, the application and granted patent disclosed the invention in the same way. No subject matter had been added.
5. Exclusive licence. Although unnecessary to the result, the evidence established an oral agreement granting Select the exclusive right to exploit the patent and related developments in return for royalties. The patent was nevertheless invalid for obviousness. The precise form of order was left for agreement or further argument.