The Formstein defence in action in the UK

12 Dec 2022 | Newsletter

Michael Hicks and Jamie Muir Wood – Hogarth Chambers, UK

On 24 August 2022, Nicholas Caddick QC (sitting as a deputy High Court Judge), handed down judgment in Vernacare v. Moulded Fibre Products [2022] EWHC 2197 (IPEC) (Link).  The case involved two patents concerned, respectively, with the configuration of open topped moulded fibre wash bowls and their composition.

Since the introduction into English law of a stand-alone test for infringement by equivalents, the English courts have continued to develop checks and balances on the doctrine. The courts had previously considered whether the German Formstein defence could be applied in the UK; the Judge in Vernacare decided that it can.

The configuration patent had previously been litigated in Vernacare v. Environmental Pulp Products [2012] EWPCC 41 in which HHJ Birss QC, as he then was, found the patent to be valid and infringed by two products but not by a third.  Claim 1 of the patent read as follows:

An upwardly open wash bowl manufactured from maceratable, dried moulded paper pulp, the wash bowl comprising a base wall and an enclosing wall extending upwardly from the periphery of the base wall and defining a liquid-receiving volume, the enclosing wall comprising recesses located on opposite sides of the liquid-receiving volume below the upper periphery of the enclosing wall and forming grip means located below the upper periphery of the enclosing wall for facilitating lifting.”

The patent explained:

By providing recesses in the enclosing wall, it is not necessary to rely on a peripheral lip in order to lift the bowl when full and thus the likelihood of disintegration of a filled bowl is greatly reduced.  In addition, by having recesses in the enclosed wall, a more rigid structure is produced.”

HHJ Birss QC decided that the claim required the recesses to have “sides in order to impart their rigidity”.  The third product, which had a continuous sinusoidal ridge running round it was found not to have the necessary recesses.

In the more recent case, the defendant’s product had a similar, but more pronounced continuous sinusoidal ridge running round the wash bowl than the third product in the earlier case.  Mr Caddick QC held that the claim was valid but not infringed.  He held that on a ‘normal’ or purposive interpretation of the claim the continuous sinusoidal ridge or shoulder did not constitute “recesses” in the enclosing wall.

The claimant argued that even if there was no infringement on a normal interpretation of the claim, the defendant’s sinusoidal ridge was the functional equivalent of recesses and therefore infringed on the basis of the doctrine of equivalents (see Actavis v. Ely Lilly [2017] UKSC 48).  In response the defendant argued that the Formstein defence was a complete answer to that argument.

The Judge considered that it was arguable that the sinusoidal ridge achieved the same result in substantially the same way as the recess of the claim.  He then went on to consider the decision of Birss LJ in Facebook v. Voxer [2021] EWHC 1377 and the third Actavis question, namely “Would such a reader of the patent have concluded that the patentee nonetheless intended that strict compliance with the literal meaning of the relevant claim(s) of the patent was an essential requirement of the invention?”

In Facebook Birss LJ said that in previous cases UK Judges had recognised Formstein as a possible way forward, but had not had to “confront the issue” (see Technetix v. Teleste [2019] EWHC 126 (IPEC) and E Mishan v. Hozelock [2019] EWHC 991 (Pat)). However, Birss LJ went on to conclude “As things have turned out in this case, I do not have to do so either.

In Vernacare the Judge concluded that a skilled person, knowing that ridges were an obvious way of strengthening a moulded fibre product would have concluded that the patentee intended there to be strict compliance with the literal (i.e. normal, purposive) meaning of the claim, because the claim would otherwise be invalid for obviousness.

Accordingly, the equivalence argument failed and the Formstein defence succeeded. This is therefore the first time that the Formstein defence has determined the outcome of patent infringement proceedings in the UK.

Michael Hicks and Jamie Muir Wood represented Vernacare Limited

their instructing patent attorneys were WP Thompson