This decision of the Courts of Appeal related to a declaration of non-infringement of a claim and considered jurisdictional points in relation to declarations in other European jurisdictions. The issue of non-infringement was primarily based on the construction of the claim.
This was a successful appeal by Lilly from the decision of Arnold J ( EWHC 1511 (Pat).
The lead judgment was given by Floyd LJ, the other judges agreeing.
This case relates to European Patent No. 1313508 of Lilly directed towards the use of the cancer treatment pemetrexed disodium in combination with vitamin B12. An application was made by a group of European subsidiaries of Actavis plc for declarations of non-infringement in relation to various European designations of the patent for a generic product in which the active ingredient was pemetrexed diacid, pemetrexed dipotassium or pemetrexed ditromethamine. Lilly counterclaimed for threatened infringement of the UK designation.
At first instance the judge found that the claims were not infringed and granted the declarations of non-infringement. Lilly appealed against the finding of non-infringement and on jurisdictional points relating to the non-UK European designations.
The key issue was the meaning of the expression “pemetrexed disodium” to the skilled team including an oncologist and a chemist.
Floyd LJ reviewed the law on claim construction, including Kirin-Amgen Inc. v Hoechst Marion Roussel Limited  UKHL 45 and commented that:
As Lord Hoffmann stressed in Kirin-Amgen at , the Protocol questions are not legal rules, but guides more useful in some cases than in others which in appropriate cases help to decide what the skilled person would have understood the patentee to mean. On the other hand, the basic principles of purposive construction, what Lord Hoffmann called "the bedrock of patent construction", are applicable in every case…
In cases where it is useful to ask it, the second Protocol question involves asking whether it would be obvious to the skilled reader that the variant has no material effect on "the way the invention works". At  in Kirin Amgen Lord Hoffmann suggested that in future it might be better to ask, as the German courts apparently do, whether it "solves the problem underlying the invention by means which have the same technical effect". The advantage of posing the question in that way is that it avoids any assumption that the variant works at all. In both cases, however, it is axiomatic that one is concerned with what would be obvious, in the sense of immediately apparent, to the skilled reader from a reading of the specification informed by common general knowledge.
Thus, for the purposes of the assessment involved in the second Improver question, I would take it as clear that the notional addressee is not presented with information which he cannot derive from the patent or his common general knowledge about whether the variant will in fact have no material effect on the way the invention works.
Arnold J had held at first instance that it was appropriate to refer to the prosecution history when construing the claims. Floyd LJ disagreed:
The difficulty I feel with endorsing this reasoning is as follows. Firstly it assumes that the skilled reader will always read the prosecution history. I do not see why this should be so, given the limited value which, at least before the judgment in this case, it was generally recognised to have. Secondly, and more importantly, it suggests that the story told by the prosecution history of how the claims came to be drafted as they were will assist the court in preventing abuse of the system. To my mind this will be a very rare case indeed. Unless the acceptance of a restriction in a claim is to operate as some kind of estoppel against the patentee arguing for wider claims (a proposition for which neither side contended and which Jacob J rejected, at least on the basis of domestic estoppel, in Bristol Myers), there will always remain an issue as to whether the applicant needed to accept the restriction notwithstanding that he did so. In those circumstances, the light which the prosecution history sheds on the ultimate question of construction is likely to be extremely limited.
I therefore do not regard it as useful to go to the prosecution history in order to discover that the patentee accepted a restriction to his claim against an objection of lack of support in the specification. It is always open to a party attacking the patent to argue that the claims as sought to be construed by the patentee lack support in the specification: see for example American Home Products v Novartis  RPC 8 at . What purpose does it serve to illustrate this point by showing that the patentee was faced with an official objection to that effect and amended his claims in the light of it? It is still open to the patentee to say that he need not have done so, and the apparent concession he made in prosecution was wrongly made. If it is not open to the patentee so to contend, then the prosecution history is indeed creating a form of estoppel.
In any event, patent offices are usually concerned with patentability, not scope of protection. If an applicant were to conclude every letter by saying that he did not accept that by accepting this or that limitation he was necessarily restricting the scope of protection, no inference could be drawn from his conduct in accepting it. I would be reluctant to put the patent attorneys' profession to this unnecessary trouble.
Floyd LJ applied the Protocol Questions and agreed with Arnold J that the Actavis variants had no material effect on the way the invention worked (first Protocol Question); but that this would not have been known to the skilled team (second Protocol Question) as in the absence of further information it would not have been clear whether the variants were sufficiently soluble; and that the skilled team would have understood that the claims were limited to the disodium salt (third Protocol Question). Thus, pemetrexed diacid, pemetrexed dipotassium or pemetrexed ditromethamine were not covered by the claim.
Floyd LJ went on to consider whether the claim was limited to pemetrexed disodium in solid form. He concluded that an injectable solution of pemetrexed ions and sodium ions arrived at by dissolving pemetrexed disodium in water would also be covered:
One question is therefore whether an identical solution containing pemetrexed and sodium ions, but arrived at in a different way, would also be thought by the skilled reader to fall within the ambit of the language. I consider that it would be. I can see no reason why the skilled reader who understands from the specification that a solution containing pemetrexed ions and sodium ions is regarded as pemetrexed disodium should assume that the method by which that solution is prepared was of concern to the patentee. That is a matter of history, and has no bearing on the essential characteristics of what is called for by the term.
A second question is whether the skilled person would understand that the ratio of sodium ions to pemetrexed ions in the solid state (i.e. 2:1) should be maintained in the solution. I am fully prepared to accept that the ratio must reach the threshold of 2:1: anything less would not meet the description "disodium". However I cannot see why the presence of more sodium ions, i.e. in excess of the 2:1 ratio should be regarded as material. Pemetrexed disodium in the sense called for by the claim would still be present, despite the presence of more sodium ions.
A final question is whether the presence of ions other than sodium could take the solution out of the claim. Again, I do not see why this should be so. A patent claim is normally to be construed as setting a set of requirements which must be present in the alleged infringement. Infringement is not generally avoided if the alleged infringement has all those features and adds something more.
This was contrary to the construction adopted by Arnold J.
Based on his construction of “pemetrexed sodium” as excluding the Actavis variants pemetrexed diacid, pemetrexed dipotassium and pemetrexed ditromethamine Floyd LJ agreed with Arnold J that there was no direct infringement.
Floyd LJ went on to consider whether indirect infringement under s. 60(2) Patents Act 1977 would occur when the Actavis variants were to be made up by a doctor or pharmacist in saline (a solution containing sodium ions), with the Actavis variants being means relating to an essential element of the invention. Based on his construction of “pemetrexed disodium” as covering an injectable solution of pemetrexed ions and sodium ions of the type arrived at by dissolving pemetrexed disodium in water, he held that there would be indirect infringement.
The judge thus held that declarations of non-infringement should not be granted in relation to any of the European designations.
The judge noted that the Düsseldorf Oberlandesgericht (appeal court) had reached a different decision on indirect infringement.
Although it was not necessary for the judge to decide these issues, he agreed with the first instance judgment. His analysis was set out at length in the judgment.
After the draft judgment was circulated, Actavis requested modifications to make it clear that sale of the Actavis variants would only constitute indirect infringement under certain conditions. Floyd LJ did not agree to this, but agreed to remit the case to the Patents Court to consider the infringement position where the Actavis variants were reconstituted with dextrose.