12 July 2017

UK Supreme Court restates English law on equivalents

Yesterday, 12th July, the UK Supreme Court (UKSC) handed down its landmark judgement [2017] UKSC 48 in favour of Eli Lilly’s dispute with Actavis concerning sales in Europe of a generic version of Lilly’s anti-cancer combination drug pemetrexed disodium and vitamin B12. Overturning the decision of the Court of Appeal, the UKSC found infringement of Lilly’s patents in the UK, France, Italy, and Spain. The impact of this decision is significant, since it not only considered the approach to claim construction, but also considers how infringement ‘equivalence’ should be assessed under English patent law. In effect, Lord Neuberger’s judgement (with unanimous agreement from the other 4 law lords) reformulates the original Improver questions for assessing the infringement of “equivalents”.

Important also, is the UKSC’s review of this approach within other EPC jurisdictions and its consideration of whether the prosecution history should play any part in deciding infringement.  These and other aspects will be explored in future articles.  However, the most significant aspect of this decision is the UKSC’s approach to the assessment of infringement of “equivalents”.

Following Lord Hoffmann’s judgement in the House of Lord’s decision Kirin-Amgen Inc v Hoechst Marion Roussel Ltd [2004] UKHL 46, the approach moved away from the Improver questions to a more general approach: “what the person skilled in the art would have understood the patentee to be using the language of the claims to mean”.  This new UKSC decision marks a reversal in the approach adopted in Kirin-Amgen and re-formulates the Improver questions.

Claim 1 of the patent related to the use of pemetrexed disodium for use in combination with vitamin B12 for the treatment of cancer.  Pemetrexed is a known anti-cancer agent but had been effectively precluded from use in practice because of seriously damaging, sometimes fatal, side-effects.  The essential disclosure of the patent is that the damaging side effects could largely be avoided if pemetrexed disodium was administered together with vitamin B12.

Actavis’ products involve pemetrexed compounds being used with vitamin B12 for cancer treatments.  However, Actavis products did not contain pemtrexed disodium as the active ingredient (as claimed in Eli Lilly’s patent).  Instead, the active ingredient in Actavis’ products was pemetrexed diacid, pemetrexed ditromethamine, or pemetrexed dipotassium.

The UKSC acknowledged that there was no “literal infringement” (the UKSC’s way of describing it) so went on to look at whether Actavis’ products infringed Eli Lilly’s UK patent (as well as the French, Italian and Spanish equivalents) as variants of what was claimed.  Significantly, the UKSC considered that the Kirin-Amgen approach led to the danger of conflating the issue of claim construction with that of the scope of protection. By reformulating the Improver questions the UKSC considers this will be avoided. These now read:

“i) Notwithstanding that it is not within the literal meaning of the relevant claim(s) of the patent, does the variant achieve substantially the same result in substantially the same way as the invention, i.e. the inventive concept revealed by the patent?

ii) Would it be obvious to the person skilled in the art, reading the patent at the priority date, but knowing that the variant achieves substantially the same result as the invention, that it does so in substantially the same way as the invention?

iii) 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 order to establish infringement in a case where there is no literal infringement, a patentee would have to establish that the answer to the first two questions was “yes” and that the answer to the third question was “no”.”

The key difference with the original Improver questions relates to the second question. The impact of this reformulation will be explored in our subsequent, in depth article.

What Lord Neuberger’s decision has done is bring into UK IP jurisprudence, the scope of Article 69 EPC and the Protocol on Interpretation, as well as the amendments effected by EPC 2000 and Article 2 relating to equivalents. It also identifies other jurisdictions’ approaches as being in step with that in the UK.