Eli Lilly v Actavis UK Ltd & Ors [2017] UKSC 48

Eli Lilly's patent covered pemetrexed disodium with vitamin B12 for cancer treatment. Actavis sought to market products using other pemetrexed salts and the free acid. The Supreme Court held these directly infringed under a reformulated doctrine of equivalents, marking a significant shift in UK patent law.

Facts

Eli Lilly held European Patent (UK) No 1 313 508, which claimed the use of pemetrexed disodium in the manufacture of a medicament for combination with vitamin B12 to treat cancer (marketed as Alimta since 2004). The invention addressed the serious, sometimes fatal, side-effects of pemetrexed when used alone. Actavis proposed to market three products using, respectively, pemetrexed free acid, pemetrexed ditromethamine, and pemetrexed dipotassium, each combined with vitamin B12. Actavis sought declarations of non-infringement; Lilly counterclaimed for threatened infringement in the UK, France, Italy and Spain.

Arnold J held there was no infringement (direct or indirect). The Court of Appeal held there was indirect but not direct infringement. Both parties appealed to the Supreme Court.

Issues

The principal issues were:

• The correct approach under UK law (and the laws of France, Italy and Spain) to interpreting patent claims, particularly the requirement under Article 2 of the Protocol on the Interpretation of Article 69 EPC 2000 to take account of equivalents.
• The extent to which the prosecution history of a patent may be used in determining scope of protection.
• Whether indirect infringement was established under section 60(2) of the Patents Act 1977.

Arguments

Lilly contended that the Actavis products embodied the essence of the invention – a pemetrexed compound used with vitamin B12 – and infringed either directly (via the doctrine of equivalents) or indirectly (because the products would be dissolved in saline, producing pemetrexed disodium in solution).

Actavis argued that the claims were expressly limited to pemetrexed disodium, that as a matter of ordinary language their products fell outside the claims, and that the prosecution history confirmed this narrow limitation. They also argued against indirect infringement on the basis that the dissolved solution did not contain pemetrexed disodium and that any infringement would depend irrationally on solvent and dosage.

Judgment

Direct infringement and the reformulated approach

Lord Neuberger (with whom Lord Mance, Lord Clarke, Lord Sumption and Lord Hodge agreed) held that infringement should be approached by addressing two issues: (i) whether the variant infringes on a normal interpretation of the claim; and (ii) if not, whether it nonetheless infringes because it varies from the invention in an immaterial way. He held that the Court in Kirin-Amgen had wrongly conflated these into a single question of interpretation.

His Lordship reformulated the Improver questions as follows:

• Does the variant achieve substantially the same result in substantially the same way as the inventive concept revealed by the patent?
• Would it be obvious to the skilled person, 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?
• Would such a reader have concluded that the patentee nonetheless intended that strict compliance with the literal meaning of the claims was an essential requirement of the invention?

The critical change was to the second question: the notional addressee is now to be assumed to know that the variant works, removing the previously high burden on patentees.

Applying this approach: (1) the Actavis products plainly achieved the same result in the same way (delivery of the pemetrexed anion with vitamin B12); (2) the skilled addressee, knowing the variants worked, would find it obvious they worked in the same way, given that salt screening was routine and the free acid, dipotassium and ditromethamine salts were established; (3) the addressee would not have concluded that strict compliance with “pemetrexed disodium” was essential – there was no plausible reason for so narrow a limitation, and the specification gave no teaching as to the importance of the sodium cation.

Prosecution history

Lord Neuberger held that reference to the prosecution file should be permitted only where: (i) the point at issue is genuinely unclear on the specification and claims and the file unambiguously resolves it; or (ii) it would be contrary to the public interest to ignore the file. The narrowing of the claims to pemetrexed disodium during prosecution (in response to added matter/disclosure objections) was held not to affect the scope of protection under the doctrine of equivalents, since the doctrine specifically extends protection beyond the literal claims.

France, Italy and Spain

Applying the relevant national doctrines of equivalents, the Court held the Patent was directly infringed in each jurisdiction. In France the Patent fell into the moyens généraux category. In Italy the Court rejected Arnold J’s conclusions on the doctrine and prosecution history. In Spain, judicial comity suggested Spanish courts would follow the reformulated Improver approach. A late application by Actavis to reopen the Spanish issue based on the Lundbeck decision was refused.

Indirect infringement

Although strictly unnecessary given direct infringement was established, the Court upheld the Court of Appeal’s conclusion on indirect infringement. When dissolved in saline, the Actavis products produce a solution chemically containing pemetrexed disodium, so the products constitute means relating to an essential element of the invention under section 60(2) of the 1977 Act.

Implications

This decision marks a significant development in UK patent law. The Supreme Court has expressly recognised that the question of infringement involves two distinct issues – normal interpretation and equivalents – and is no longer to be treated as a single exercise in purposive construction. This brings UK law closer to German, Dutch, Italian and French approaches and gives effect to Article 2 of the Protocol.

The reformulated second Improver question lowers the bar for patentees by assuming the skilled addressee knows the variant works. This is likely to broaden the effective scope of patent protection, particularly in pharmaceutical cases where minor chemical substitutions (such as alternative salt forms or counter-ions) are made.

The Court also clarified that reference to the prosecution history will be permitted only in narrow circumstances, preserving legal certainty for third parties while leaving room for justice in exceptional cases. Importantly, narrowing amendments made during prosecution to address disclosure or added matter objections do not necessarily restrict the doctrine of equivalents.

The decision is of particular significance to the pharmaceutical sector, generics manufacturers, and patent litigators across Europe, signalling greater convergence in approach across EPC jurisdictions. It also illustrates the limits of literalism in patent claim construction and reinforces the principle that patent protection should not be defeated by immaterial variations.

Verdict: The Supreme Court allowed Eli Lilly’s appeal and held that the Actavis products (containing pemetrexed free acid, pemetrexed ditromethamine, and pemetrexed dipotassium) directly infringed the Patent in the United Kingdom, France, Italy and Spain. Actavis’s cross-appeal was dismissed on the basis that, had the products not directly infringed, they would have indirectly infringed to the extent held by the Court of Appeal.

Source: Eli Lilly v Actavis UK Ltd & Ors [2017] UKSC 48