14 Apr 2020

Technetix V Telestre: Equivalence and "The Gillette Defence"

One of the questions that has preoccupied patent pundits since the Supreme Court first introduced a doctrine of equivalents into the UK patent system in Actavis v Eli Lilly ([2017] UKSC 48) is the fact of the so-called "Gillette Defence". Is it still a defence against patent infringement to do something which differs from the prior art only in non-patentable ways?

That question has now been considered by HHJ Hacon in Technetix v Telestre ([2019] EWHC 126(IPEC)). HHJ Hacon first noted that it has long been a principle of UK patent law that a patentee should not be able to prevent a person from doing whatever he or she had lawfully been entitled to do before the patent was granted. He stated that it would be surprising if the Supreme Court in Actavis had intended to abandon this long-held principle without expressly saying so. He then referred to similar principles that hold in countries that also have a doctrine of equivalents, namely the Formstein defence in Germany and the ensnarement principle in the US. HHJ Hacon felt that the Supreme Court may in due course introduce some form of Formstein defence into English law. He considered the facts of this case on the hypothesis that such a defence exists.

Under the Formstein defence, a product does not fall within the scope of a patent if it is anticipated by or obvious over the state of the art. Its purpose is to stop the patent from being extended via equivalency to cover subject-matter which is within the state of the art, and for which the patentee could not have obtained protection in examination proceedings. In this case, HHJ Hacon decided that if a Formstein defence exists in English law, defendants Telestre were entitled to that defence. He also commented that the Formstein defence provides a squeeze on infringement, noting that where the simplicity of the inventive concept tends to make the scope of the claim broader, this will also increase the likelihood that a Formstein defence will apply.