LSIPR webinar: HGF on doctrine of equivalence evolution
The case of Actavis v Eli Lilly introduced “a real change in the law” and the way in which it addresses the doctrine of equivalence, according to Douglas Drysdale, partner at HGF in Glasgow, UK.
Drysdale explored the changes brought about by the UK Supreme Court’s 2017 decision during a joint webinar between LSIPR and HGF on Thursday, October 11.
Under the doctrine of equivalence, patent infringement can be determined even when the infringing device does not fall into the literal scope of the patent’s claims, where that device is equivalent to the claimed invention.
Last year’s landmark decision reformulated the questions that should be asked when testing for infringement under the doctrine of equivalence by reworking the so-called Improver questions, Drysdale explained.
In the 1990 case of Improver Corp v Remington Consumer Products, Lord Hoffmann, then Justice Hoffmann, formulated the three questions that should be asked when the allegedly infringing element falls outside the literal meaning of the patent claim language (the ‘variant’).
These were, whether the variant has a material effect on the way the invention works; if not, whether this would have been obvious to someone skilled in the art when the patent was published; and, if yes, whether that person would have understood that strict compliance with the language of the patent was an essential requirement of the invention.
Drysdale explained that, under the Improver questions, the variant is not infringing if those questions are answered, in order, as yes, no, and yes.
Later, in 2004, Hoffmann went on to rule that the scope of a patent claim should be assessed solely on the basis of a purposive construction (Kirin Amgen v TKT). Drysdale said that this ruling “really defined” this area of the law some time.
However, in Actavis, Lord Neuberger disagreed with—and set aside—Hoffmann’s precedent in Kirin Amgen.
Drysdale said that, in the Actavis case, Neuberger went back to basics in considering how we look at the interpretation of patents and the scope of their claims.
Diverging from Hoffmann’s stance in Kirin Amgen, Neuberger said it is unlikely that a person skilled in the art would determine that a patent owner intended to exclude certain equivalents from the patent’s scope of protection, based on the wording of the claim.
“Neuberger looked back to Improver and said that there are too many hurdles,” Drysdale noted. As a result, Neuberger reformulated the questions with a particularly important change to the second one.
The second question now asks whether it would be obvious to a person skilled in the art, who knows that the variant achieves substantially the same result as the invention, that the variant does so in substantially the same way as the invention.
Drysdale noted that Neuberger’s test “gives the skilled person an awful lot of knowledge”, as under Improver, the skilled person only had the knowledge available at the time that the patent was published.
Under Actavis, the skilled person has the foreknowledge that the variant achieves substantially the same result as the invention, Drysdale explained.
Drysdale’s exploration of the doctrine of equivalence comes shortly after Laurence Gainey, patent director at HGF’s Manchester office, UK, considered the history of personalised healthcare inventions and second medical use patents in Europe in a joint webinar between LSIPR and HGF.
Earlier this year, Catherine Coombes, patent director at HGF, and Chris Moore, partner at HGF, discussed updates and trends in opposition and appeal proceedings at the European Patent Office in another joint webinar.
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