Nigel Jones
Partner, Head of Intellectual Property and Co-Head of
Healthcare, Linklaters, London

David Marsh
Partner, Arnold & Porter, LLP, Washington, DC

This article considers the potential impact for the international pharmaceutical and biotechnology industries of decisions from a US 1 and a UK 2 court given within a week of each other in October 2004. It reviews the different conclusions reached by the courts in these two key jurisdictions, and the underlying legal bases on which they were based; and it discusses the practical implications for patent-owners in these industries.

The underlying patents related to the same invention, Amgen’s invention of how to use its discovery of the gene sequence for erythropoeitin (‘EPO’), and the same allegedly infringing product, TKT’s so-called ‘gene-activated erythropoeitin’ (or ‘GAEPO’). However the two courts came to diametrically opposed conclusions. The Boston court held the relevant Amgen US patents valid and infringed; but the United Kingdom’s House of Lords decided that not only did GA-EPO not infringe the counterpart European patent, but also that the patent was invalid. In doing so, the House of Lords changed the longstanding English law test for non-literal infringement of patents (variously referred to as the ‘Catnic Test’ or the ‘Protocol Questions’), and openly rejected the US courts’ doctine of equivalents approach as being inappropriate and unnecessarily complex (and expensive) to apply. This is how it was put in the leading judgment, given by Lord Hoffmann:

If literalism in construing patent claims stands in the way of construing patent claims so as to give fair protection to the patentee, there are two things that you can do. One is to adhere to literalism in construing the claims and evolve a doctrine which supplements the claims by extending protection to equivalents. That is what the Americans have done. The other is to abandon literalism. That is what [we, the English House of Lords, did by adopting] a principle of construction which actually gave effect to what the person skilled in the art would have understood the patentee to be claiming. [This, combined with the Protocol to Article 69 EPC] firmly shuts the door on any doctrine which extends protection outside the claims. I cannot say that I am sorry because the [US] Festo litigation suggests, with all respect to the courts of the United States, that American patent litigants pay dearly for results which are no more just or predictable than could be achieved by simply reading the claims. 3

The House also changed English law on the novelty test for product-by-process claims, and sought to clarify the application to biotech patents of the European insufficiency test for validity. Whilst these two issues were not specifically considered by the Boston court in its decision on Amgen’s counterpart US patents, this article will also briefly comment on the extent to which English and US law are in line in these areas.

The facts and the history of the cases
Amgen sequenced the EPO gene in the early 1980s. As a result, it became possible to make EPO using recombinant DNA techniques which were well known at the time, in quantities sufficient to treat patients with a range of conditions, in particular anaemia. The resulting product became a blockbuster pharmaceutical product, and has been and continues to be of enormous benefit to patients worldwide.

Amgen produced its recombinant EPO by introducing the EPO gene, in a bacterial plasmid and combined with a powerful viral promoter, into mammalian cells. Later, TKT developed a new way of making recombinant EPO. Its technique involves expressing the endogenous EPO gene at a higher level in a human cell by introducing the necessary control sequence and ‘other bits of machinery’ (as Lord Hoffmann put it) at precisely the right point upstream of the EPO gene. This is done by a technique known as ‘homologous recombination’ and results in the endogenous gene being switched on to produce EPO. This could not have been done in the early 1980s when Amgen made its invention.

European claims and history
The claims covering this invention differed in Europe and in the United States, and within each set of patents. Those relevant for the English proceedings were Claims 1, 19 and 26. In summary, Claim 1 covered the EPO-encoding DNA sequence; Claim 19 covered the recombinant polypeptide product of the expression of this ‘exogenous DNA sequence’, with the added requirement that the product have ‘a higher molecular weight by SDS-PAGE from [EPO] isolated from urinary sources’; and Claim 26 covered the polypeptide product of expression in a eukaryotic host cell of a DNA sequence according to Claim 1.

The history of how the claims came to be in this form is long and complex, and has been covered elsewhere.4 Suffice it to say that, as far as the European patent is concerned, it had been through the mill at the European Patent Office on several occasions, and survived in this form. It had also been extensively litigated in a number of courts in Europe, and counterpart claims had also been litigated elsewhere, notably Canada and Australia, and in many cases had been upheld and found infringed (although not by TKT’s GA-EPO). Particularly relevant here is the fact that the EPO’s Technical Board of Appeal had held Claim 26 (a product-by-process claim) and Claim 19 to be valid (rejecting arguments that it lacked novelty, in the case of Claim 19, once the ‘higher molecular weight’ requirement had been added).

At first instance, Claim 19 was held invalid (for insufficiency) but Claim 26 was held valid and infringed. The Court of Appeal held that both claims were valid, but that neither was infringed. Both courts grappled with the way in which the Protocol questions and the Biogen insufficiency test should be applied, and came to different conclusions. Both sides appealed the Court of Appeal judgment: Amgen against the decision that, as a matter of construction, the TKT process was not within the claims; and TKT against the rejection of its attack on the claims for insufficiency and (for Claim 26) anticipation.

US claims and history
The position in the United States is more complex.

In June 1999, Amgen brought an action in the District Court for the District of Massachusetts (‘the District Court’) asserting that Hoechst Marion Roussel, Inc (‘Hoechst’) and TKT infringed claims of five US patents assigned to Amgen. 5 In Amgen, Inc v Hoechst Marion Roussel, Inc, Amgen asserted claims from five patents with an identical specification. 6

Judge Young of the District Court originally held that Claims 1, 2 and 9 of the ‘933 patent were not infringed, and, if this finding was in error, those claims were invalid for lack of an adequate written description, indefiniteness, and lack of enablement. He also held that Claims 4 through 9 of the ‘698 patent were not infringed and that Claims 2 through 4 of the ‘080 patent were valid, enforceable, and infringed under the doctrine of equivalents. He further held that Claims 1, 2, 4, and 6 of the ‘349 patent were valid, enforceable, and literally infringed, whereas Claim 7 of the same patent was not infringed. Lastly, he held that Claim 1 of the ‘422 patent was valid, enforceable, and literally infringed.

The US Court of Appeals for the Federal Circuit (‘the Federal Circuit’) affirmed that all of the patents in suit were enforceable, affirmed that the District Court’s finding that the ‘933 patent was invalid and affirmed that the ‘422 patent claims and the product claims of the ‘349 patent were infringed. The Federal Circuit vacated the District Court’s finding that the ‘933 patent was not infringed, several of the validity findings with respect to the ‘080, ‘349, ‘422, and ‘698 patents, and the infringement findings with respect to the ‘698 patent and Claim 7 of the ‘349 patent. The Federal Circuit further remanded the case to the District Court directing it to construe the claim term ‘therapeutically effective’7 and then to reconsider validity under 35 USC §§ 102 and 103 in view of Goldwasser; to reconsider validity of all asserted claims under 35 USC § 103 and Claim 1 of the ‘422 patent under 35 USC § 102 in view of Sugimoto, with Amgen bearing the burden of proof on its non-enablement (for 35 USC § 102 purposes only). The Federal Circuit also remanded the case for the District Court to reassess infringement of the accused method by comparing it solely to the limitations of each of the asserted method claims, and to re-evaluate its finding of infringement under the doctrine of equivalents of the ‘080 patent, focusing on the application of prosecution history estoppel.

On 15 October 2004, Judge Young issued his opinion on the remanded issues holding that Claim 1 of the ‘422 patent is valid, Claims 2 to 4 of the ‘080 patent are valid, Claims 4 to 9 of the ‘698 patent are valid and literally infringed, and Claim 7 of the ‘349 patent is valid and literally infringed.

Infringement: What is the Test?

England
In considering the law of infringement, Lord Hoffmann (with whom the other four Lords Justice concurred) reviewed the way in which the modern approach to claim construction had developed in the courts in England and elsewhere in Europe (particularly Germany). He considered the position both before and after the European Patent Convention was introduced. He then contrasted these approaches with that of the US courts. He emphasized the importance, both for the public and the patentee, of being able to set clear limits on the scope of the monopoly claimed, but also of not taking too literal or legalistic an approach to claim interpretation. Drawing analogies with the English law approach to contractual interpretation, he emphasized the importance of recognizing that the author of a document uses language to make a communication for a practical purpose, and that the key therefore is to understand what the notional addressee of the document would have understood the author to be using the words to mean.

He said that, in essence, that is all the Catnic/Protocol questions were intended to achieve. They were an aid to finding the answer to this key question, not a hard and fast test to be applied in all circumstances.8 So too with Article 69 of the European Patent Convention, and its Protocol, requiring as they do a construction of the claims which achieves a balance between fair protection for the patentee and reasonable certainty for third parties; and with the approach of courts elsewhere in Europe. Although those courts use different words, they have, in Lord Hoffmann’s view, established tests which are designed to address the same fundamental question. After reviewing the way in which the first instance judge and the Court of Appeal approached this question, and agreeing with the latter’s conclusion that there was no infringement, Lord Hoffmann set out in terms the test which he considered should be applied when considering non-literal infringement. In what one assumes cannot have been mere coincidence, he does so in paragraph 69 (matching the EPC Article number, to make things easy for everyone to remember!), as follows:

The determination of the extent of protection conferred by a European patent is an examination in which there is only one compulsory question namely that set by article 69 and its Protocol: what would a person skilled in the art have understood the patentee to have used the language of the claim to mean? Everything else, including the Protocol questions, is only guidance to a judge trying to answer that question. But there is no point in going through the motions of answering the Protocol questions when you cannot sensibly do so until you have construed the claim. In such a case – and the present is in my opinion such a case – they simply provide a formal justification for a conclusion which has already been reached on other grounds. (emphasis added)

He accepted that it is easy to say this and sometimes more difficult to apply it in practice (although he indicated that the difficulty had in the past perhaps been exaggerated). 9 He also offered some sympathy for those now faced with no clear set of questions to apply in this difficult area:

No doubt there will be patent lawyers who are dismayed at the notion that the Protocol questions do not provide an answer in every case. They may feel cast adrift on a sea of interpretative uncertainty. But that is the fate of all who have to understand what people mean by using language. The Protocol question are useful in many cases, but they are not a substitute for trying to understand what the person skilled in the art would have understood the patentee to mean by the language of the claims. 10

The discussion which follows, of the comparison of this approach with that of the US courts, will consider where this leaves those in the industry when drafting or considering the interpretation of biotech patent claims. But two short points before moving on. First, Hoffmann reiterated that there was no place in English law (or indeed, in his view, in the law elsewhere in Europe) for any form of file wrapper estoppel. Secondly, by saying nothing about the date on which the test is to be applied, it is assumed that it remains the date of publication of the patent application not, as elsewhere, the date of infringement.

The United States
Approximately seven years ago, the United States Supreme Court in Markman established that the interpretation of patent claims was ‘exclusively within the province of the court’. 11

Many Federal Circuit and District Court opinions subsequent to Markman have focused on claim interpretation issues, and particularly the methodologies that are or should be applied to claim interpretation. 12 Many commentators have noted variation between Federal Circuit panels in the application of claim construction canons, particularly the canons that the claim language is read in light of the specification of which it is part and that the meaning of claim language may not be altered by importing or reading-in charges from outside the claims. 13

The Federal Circuit in Johnson Worldwide Associates, stated that the ‘general rule is, of course, that terms in the claim are given their ordinary and accustomed meaning’. 14 Two situations are highlighted by the Federal Circuit as situations where a sufficient reason exists to require a definition other than its ordinary and accustomed meaning: 15 first, when the patentee has chosen to be his or her own lexicographer; and secondly, where the scope of the claim cannot be ascertained from the language of the claim.16 In Amgen, an issue on remand was whether an exception to the general rule that a term must be given its ordinary and accustomed meaning applied to the terms ‘therapeutically effective’ and ‘DNA encoding’. 17

‘Therapeutically effective’
On remand, Judge Young was tasked by the Federal Circuit with interpreting the phrase ‘therapeutically effective’. Amgen argued for the adoption of the ordinary meaning and that the expert testimony supports that the ordinary meaning of ‘therapeutically effective’ referred to an amount sufficient to produce a sustained increase in hematocrit, not merely an amount sufficient to produce a biological effect. In doing so,

Amgen argued that (1) the other effects listed in the specification were biological effects; (2) the specification as a whole supports the plain meaning of ‘therapeutically effective’; (3) the prosecution history distinguished naturally occurring EPO because it was not an effective human therapeutic; and (4) the doctrine of claim differentiation required the adoption of the ordinary meaning of ‘therapeutically effective’. In contrast, TKT argued that ‘therapeutically effective’ referred to and included any of the biological effects set forth in the specification.18

Analytically, the District Court first looked to the ordinary meaning of ‘therapeutically effective’ using various dictionaries as its guide.19 Based on these definitions, the District Court concluded that ‘therapeutically effective’ was related to medical treatment and consistent with Amgen’s asserted definition. Secondly, the District Court looked to the claims, specification, and prosecution history to determine whether Amgen redefined the ordinary meaning of the phrase. 20

Upon remand, the District Court noted that the Federal Circuit highlighted that the specification set forth a number of biological attributes such as the development of ferrokinetic effects. 21 TKT argued that this reference modified the ordinary meaning of ‘therapeutically effective’ and that increasing hematocrit levels was only one of the many biological effects and an attribute previously attributed to naturally occurring EPO. 22 The District Court rejected this argument, concluding that the claims, specification, and prosecution history did not ‘broaden[ed] the plain meaning of the term ‘therapeutically effective’ to encompass the elicitation of non-hematocrit biological effects’.

In doing so, the District Court found that an increase in hematocrit levels was not previously attributed to naturally occurring EPO and that careful paring of the words in the specification combined with statements made by Amgen during prosecution that an increase in hematocrit levels was used consistently with the ordinary meaning of ‘therapeutically effective’ and such usage differed from how the specification and the prosecution history treated biological activities such as the development of ferrokinetic effects. 23 The District Court focused on statements by Amgen that distinguished recombinant EPO from naturally occurring EPO during patent prosecution, which included that naturally occurring EPO was ‘not a viable therapeutic product’ 24 and that ‘[i]n contrast to recombinant erythropoietin naturally-occurring human erythropoietin is not used to treat patients’. 25 The District Court further noted that the claims themselves and the dictionary definitions relied upon provided no guidance on the disease state to be cured and concluded that the therapeutical effectiveness should be judged relative to the patient groups set out in the specification. 26

‘DNA encoding’
The District Court’s original judgment of non-infringement of Claims 4 to 9 of the ‘698 patent was remanded. On remand, the parties focused on the meaning of the phrase ‘DNA encoding the mature erythropoietin amino acid sequence of FIG. 6’.27 TKT asserted that the phrase requires that the DNA actually produces a glycosylated erythropoietin of 166 amino acids. Amgen disagreed, stating that the phrase does not require a 166 amino acid EPO to be produced but merely that DNA encodes the 166 amino acid EPO even when the end result is not a 166 amino acid EPO.

The District Court rejected TKT’s interpretation, finding that the ordinary meaning that ‘DNA encoding’ 28 ‘is DNA that converts one type of message or text into another type of message and that it provides information to the cell’. 29 In short, the District Court summarised this characteristic as ‘the generic instructions for’. 30 In so doing, the District Court concluded that the claims and the specification supported adopting the ordinary meaning. 31

Reverse doctrine of equivalents
TKT asserted that the reverse doctrine of equivalents should apply. The reverse doctrine of equivalents is an equitable doctrine that a court applies when it finds that the accused device literally infringes a patented invention, but is so fundamentally different from the patented invention that a judgment of infringement would be inappropriate. The reverse doctrine of equivalents is applied equitably based upon factual determinations made after ‘the accused infringer proves that, despite the asserted claims literally reading on the accused devise, "it has been so changed that it is no longer the same invention"’. 32 Although the Federal Circuit recognises this doctrine, it is rarely invoked successfully.33 The District Court noted that:

[T]he reverse doctrine of equivalents should not be invoked frequently. To the contrary, it should be saved – and apparently is – for the inventor that radically, not just modestly, improves upon the prior art such that there is a ‘manifest departure from the principle in the [patentee’s] patent’.

TKT asserted that its process, based on homologous recombination, which was unknown at the time of Amgen’s patent filing, is ‘so far removed in terms of its principles of operation from the process Amgen disclosed’. Although the District Court agreed that TKT showed many differences, it nonetheless failed to prove that these differences mattered.34 The District Court noted that, with the exception of a ‘neighbourhood theory’, TKT had failed to explain why the differences in the approach mattered.

TKT pointed to expert testimony that suggested that the area (‘neighbourhood’) around the EPO gene affects expression capability. 35 TKT suggested that activation of the endogenous, normally silent EPO gene by a viral promoter works in concert with nearby enhancers and the EPO gene’s neighbourhood. While the District Court stated that such a mechanism ‘might well have justified invocation of the reverse doctrine of equivalents’, it concluded that TKT failed to present sufficient evidence on the issue.

Novelty of product-by-process claims
Product-by-process claims had, until this decision, been treated as passing the novelty test in England if the relevant product was made by a new process, even if the resulting product was identical to one which was already part of the state of the art. This was at odds with the approach of Patent Offices and courts elsewhere in Europe, and with the EPO’s approach. Lord Hoffmann also accepted that it was illogical, as the manner in which a product is made is not, as he put it ‘an attribute which it carries around and makes it something new’. He explained the reasoning as being the perceived need to provide protection in the United Kingdom for products made outside the United Kingdom using the new process: by allowing the patentee to sue the person selling the product here under the ‘product’ element of the claim.

However, he held that that reasoning was flawed: both the EPC (Article 64(2)) and its UK Patents Act equivalent (section 60(1)(c)) gave the proprietor of a process claim the right to sue the seller of a product ‘directly obtained by [the patented] process’, irrespective of where the process had been carried out. There was, therefore, no longer any justification for the United Kingdom being out of step; Merrell Dow v Norton 36 made clear the importance of the United Kingdom applying the same law as the EPO and other Member States; and English law should therefore be brought into line with that elsewhere in Europe. Product-by-process claims will therefore now only be allowed or maintained if the product itself is new, and where its difference from the state of the art cannot be described in chemical or physical terms but only by reference to the process by which it is made. 37 This change should not, he said, be of great practical importance because patentees will still be able to rely on their process claims under Article 64(3), assuming, of course, that the relevant patents include such claims.

Here, the judge had held that there was no difference between prior art EPO (from urinary sources) and EPO made according to Claim 26. Lord Hoffmann noted that this seemed at odds with the position as the EPO had understood it during opposition proceedings there, but that he was bound to follow the judge’s findings. On that basis, judged against the correct standard, the claim lacked novelty, and the Court of Appeal’s finding had to be reversed.

In the United States, the patentability of a product-by-process claim is determined based on the patentability, including novelty, of the product. 38 Hoffmann’s adoption of a similar approach to the United States brings the countries into conformity, allowing more consistent examination of product by- process claims in the United States and the United Kingdom.

Insufficiency

England
The basic test for sufficiency under English law is set out in section 72(1)(c). It provides that a patent shall be revoked if the specification does not disclose the invention ‘clearly and completely enough for it to be performed by a person skilled in the art’. Critical to the application of this test is determining what the invention is.

In the lower courts, particularly at first instance, the question of the sufficiency or otherwise of the Kirin-Amgen patent had received a great deal of attention. There had been, and were before the House of Lords, four complaints of insufficiency, some of general application, others applying only to Claim 19. Dealing with these had taken up much of the evidence, the courts’ time, and space in the judgments. Lord Hoffmann’s view was that much of this could have been avoided if it had been established earlier on what precisely the invention was: whether it was the discovery of the DNA sequence encoding EPO, or a new artificial form of EPO, or a way of making it. He held that it was the latter, and that, defined in this way, it was not enabled. This is how he summarized his views on this point:

Standing back from the detail, it is clear that Amgen have got themselves into difficulties because, having invented a perfectly good and ground-breaking process for making EPO and its analogues, they were determined to try to patent the protein itself, notwithstanding that, even when isolated, it was not new.

Before reaching that conclusion, he sought to clarify the way in which the basic insufficiency test should be applied to this type of claim, and then applied it to each of the four challenges raised by TKT. (For the purposes of this article, we will address only the first of these steps, as it is of most general application.) The key issue was whether Amgen had taught a ‘principle of general application’, as that term had been used by Lord Hoffmann in the Biogen case. 39 In a much-quoted passage, he had said this:

If the invention disclosed a principle capable of general application, the claims may be in correspondingly general terms … [I]f the patentee … has disclosed a beneficial property which is common to [a class of products] he will be entitled to a patent for all products of that class (assuming them to be new) even though he has not himself made more than one or two of them.

Amgen argued that it had disclosed such a principle, and was therefore entitled to claim it broadly; TKT disagreed. Lord Hoffmann sided with TKT. He said that all he had meant in this passage in Biogen was that if an element of a claim is stated in general terms, and one can reasonably expect the invention to work with anything falling within those general terms, the claim will be sufficient. 40 On the facts here, he held that this principle could not be applied to the Amgen claims. He said that if, as the judge thought, the claims were to be construed broadly so as to cover any way of making EPO by recombinant DNA technology, the specification did not disclose a way of making it in sufficiently general terms to include the TKT process. 41

In the context of dealing with the attack on Claim 19 specifically, he rejected Court of Appeal’s finding that the fact that it was not possible to determine whether a claim was or was not infringed – essentially a lack of clarity objection – did not necessarily mean that it was invalid for insufficiency. In his view, a claim is insufficient in these circumstances; and as a result Claim 19 was invalid.

The United States
For a claim to be enabled, 42 a specification must teach those skilled in the art to make and use the full scope of the claimed invention without the need for undue experimentation. 43 Upon remand, TKT argued that the process claims of the ‘698 patent and the ‘349 patent did not enable one of skill in the art to produce EPO from vertebrate cells other than those transfected with exogenous cloned EPO DNA. 44 Moreover, TKT argued that Amgen’s specification only enables operative linkage of promoter DNA and EPO DNA near or adjacent to the ATG initiation codon of a cloned and isolated EPO gene. 45

With respect to TKT’s first argument, the District Court agreed with TKT that endogenous activation technology and homologous recombination were not known at the time of Amgen’s filing. However, citing In re Hogan 46 and Plant Genetic Systems, NV v DeKalb Genetics Corp. 47 for the premise, the District Court stated that ‘later states of art cannot be employed as a basis for [an enablement] rejection’. 48

TKT argued that Amgen’s specification did not enable the person of ordinary skill to place the promoter further upstream from the coding region. TKT argued that Amgen had not attempted to place the promoter upstream. The District Court stated that ‘it is not necessary that a patent applicant test all the embodiments of his invention; what is necessary is that he provide a disclosure sufficient to enable one of skill in the art to carry out the invention commensurate with the scope of his claims’ 49 and that absent specific evidence 50 of undue experimentation, TKT ‘simply has not met its burden to prove undue experimentation’. 51

As is often the case in biotechnology disputes, in addition to raising an enablement issue, TKT asserted that certain claims were invalid as indefinite or for lack of written description. TKT asserted that Claims 4, 5, 6, 7, 8, and 9 of the ‘698 patent and Claim 7 of the ‘349 patent are indefinite 52 in light of the District Court claim interpretation that ‘DNA encoding’ meant genetic instructions. The Federal Circuit has stated that the standard for determining whether a claim is sufficiently definite is ‘[i]f one skilled in the art would understand the bounds of the claim when read in light of the specification’.53

TKT asserted that as the claims were silent on splicing instructions or messages, they were indefinite because the phrase ‘DNA encoding’ did not provide sufficient guidance to a skilled artisan on what DNA molecules fell within the claim. Amgen responded by stating that skilled artisans would be able to produce EPO using spliced DNA and this evidenced the fact that those skilled in the art would have known how to determine which processes fell within the scope of the claims. The District Court stated that the claim would be definite if the specification teaches skilled artisans to splice codons in the correct order and that TKT failed to establish by clear and convincing evidence that the specification failed to teach codon splicing.

Often, as here, a party challenging the definiteness of a claim will also assert that the claim lacks ‘written description’. Recent commentary and judicial opinions have focused on what is required to fulfil the written description requirement of 35 USC § 112, paragraph 1. 54 With respect to the written description requirement, citing to Reiffer v Microsoft Corp., 55 the District Court stated that the ‘disclosure as originally filed must explicitly or inherently convey to the skilled artisan that the inventor had possession at that time of the late claimed subject-matter’. Based on similar arguments that it raised in the enablement context, that Amgen failed to describe TKT's homologous recombination approach and that it failed to describe promoters further upstream than the embodiments set forth in Amgen’s specification, TKT argued that certain claims were indefinite.

In rejecting TKT’s first argument that Amgen’s specification failed to describe TKT’s homologous recombination approach the court stated that, like its approach for enablement, ‘[i]f later states of the art could be employed as a basis for rejection under 35 USC 112, the opportunity for obtaining a basic patent upon early disclosure of pioneer inventions should be abolished’.56

The District Court also rejected TKT’s second argument that Amgen’s specification failed to describe promoters placed at a distance from the ATG start codon. While agreeing that the specification only describes insertion of the promoter just upstream of the ATG, the District Court held that the claims were described based on the analysis it also set forth for enablement. 57 The District Court conclusion, discussed above, with respect to enablement, that placement of the promoter further upstream of the EPO coding was a known, understood but not yet practised application combined with the absence of statements by Amgen that ‘close proximity’ was the invention demonstrated that Amgen was in possession of the claimed invention.58

Conclusion
The fundamentally different non-literal infringement tests which must now be applied in the United States and the United Kingdom create an additional challenge for those seeking to enforce their patent rights on an international basis, particularly for inventions in the chemical and biotech fields. It may also become more challenging for those drafting biotech patents to know where to draw the line on the sufficiency/enablement issue, given the divergent conclusions on this in these two decisions. But at least there is now harmony in the test for novelty in the context of product-by-process claims.

The House of Lords has firmly rejected any notion of ‘equivalents’ (let alone reverse equivalents) and file wrapper estoppel, whereas those principles remain at the core of the approach in the United States; and there remain considerable differences in the relevant date on which the views of the skilled reader have to be ascertained (infringement for the United States, publication in the United Kingdom) and the relevance of dictionary definitions. It will, it seems, nevertheless continue to be necessary and appropriate to provide the court with evidence from experts as to what the skilled person would have thought the claim language meant; and where the claims contain biological terms, extrinsic evidence is likely to continue to play a key role in the United States, as well as in the United Kingdom, despite the US emphasis on intrinsic evidence. However, the absence of any structure to the approach to be adopted by the UK courts, at least in relation to biotech patents where the Protocol questions will seldom be relevant, will inevitably make it even more difficult to determine where a court will come out on construction and, therefore, infringement. In the United States, concerns that are often voiced with respect to claim interpretation are a perceived variation between appellate judges and the high frequency that the Federal Circuit reverses the District Court on claim construction issues.

On the positive side, the fact that the House of Lords has stated that its approach is now entirely consistent with that of courts elsewhere in Europe should, if proved to be correct, increase consistency and predictability. And the removal of the strait jacket of the Protocol questions should avoid litigants spending (many would say, wasting) time discussing with expert witnesses questions which were difficult if not impossible to address in the context of chemical or biotech patents should be good news – provided of course it ends up being quicker and easier to address the single, fundamental, question with which the Protocol questions have been replaced by the House of Lords.

The challenge on the insufficiency/enablement issue seems less significant. The basic tests in the two jurisdictions are broadly the same. Both require teaching across the scope of the claim. The main reason for the different conclusions here seems to have had more to do with the way in which the relevant claims were interpreted by each of the courts than any fundamental difference in the law; and in turn that seems largely to have been the result of the way the claims were drafted. Suggestions that the House of Lords ruling demonstrates an anti-biotech patentee bias in the United Kingdom therefore seem unfounded. Obviously, care must nevertheless be taken in drafting claims in this field to ensure that they do not end up facing the criticism faced by Amgen here.

As with many developments in patent law, at the end of the day, only time will tell how this combination of decisions affects the industry. The authors hope that this review will help those who will shape the future through the application of these two decisions.

© Nigel Jones and David Marsh, 2004

1) Amgen, Inc v Hoechst Marion Roussel, Inc, 339 F.Supp. 2d 202 (D. Mass. 2004).
2)Kirin-Amgen and others v Hoechst Marion Roussel Limited and others (respondents); Kirin-Amgen and others v Hoechst Marion Roussel Limited and others (appellants) (Conjoined Appeals), handed down on 21 October 2004, [2004] UKHL 46, on appeal from [2002] EWCA Civ 1096.

3) Ibid, paragraphs 42 to 44.

4) See, for example, Sheraton and Sharples, [2002] 12 EIPR 2002, at 596 to 599; White, [2002] CIPA Journal, 31(8), at 398 to 399; and Gilbert and Moore, [2001/2002] 4 BSLR, at 122 to 126.

5) Amgen, Inc v Hoechst Marion Roussel, Inc, 126 F.Supp. 2d 69 (D. Mass. 2001). An earlier action brought by Amgen was dismissed on jurisdictional grounds. See Amgen v Hoechst Marion Roussel, Inc, 3 F.Supp. 2d 104 (D. Mass. 1988).

6) The claims asserted were Claims 1, 2 and 9 from US Patent No. 5,547,933 (‘the ‘933 patent’); Claims 4, 5, 6, 7, 8 and 9 of US Patent No. 5,618,698 (‘the ‘698 patent’); Claims 2, 3 and 4 of US Patent No. 5,621,080 (‘the ‘080 patent’); Claims 1, 3, 4, 6 and 7 of US Patent No. 5,756,349 (‘the ‘349 patent’); and Claim 1 of US Patent No. 5,955,422 (‘the ‘422 patent’).

7) Claim 1 of the ‘422 patent recites: A pharmaceutical composition comprising a therapeutically effective amount of human erythropoietin and a pharmaceutically acceptable diluent, adjuvant or carrier, wherein said erythropoietin is purified from mammalian cells grown in culture. (emphasis added) Claim 4 of the ‘080 patent recites: A pharmaceutical composition comprising a therapeutically effective amount of an erythropoietin glycoprotein product according to Claim 1, 2, or 3. (emphasis added)

8) For example, in paragraph 52 of the judgment, Lord Hoffmann says this: ‘I am bound to say that the cases show a tendency for counsel to treat the Protocol questions as legal rules rather than guides which will in appropriate cases help to decide what the skilled man would have understood the patentee to mean. The limits to the value of the guidelines are perhaps most clearly illustrated by the present case …’.

9) See paragraph 48.

10) Paragraph 71.

11) Markman v Westview Instruments, Inc, 517 US 370, 372 (1996).

12) Indeed, many issues of claim construction are before the en banc Federal Circuit in Phillips v AWH Corp., 03–1269 to –1286 (Fed. Cir. 2004).

13) See, for example, Wagner and Petherbridge, ‘Is the Federal Circuit Succeeding? An Empirical Assessment of Judicial Performance’, 152 U. Pa. L. Rev. 1105–1180 (2003–2004); Chu, ‘Empirical Analysis of the Federal Circuit’s Claim Construction Trends’, 16 Berkeley Tech. LJ 1075, at 1078 to 1079 (1991); Duffy, ‘On Improving the Legal Process of Claim Interpretation: Administrative Alternatives’, 2 Wash. U. J.L. & Pol’y, 109 (2000); Lemley, ‘Rational Ignorance at the Patent Office,’ 95 NW. U. L. Rev. 1495, 1496 (2001); Nard, ‘Process Considerations in the Age of Markman and Mantras’, 2001 U. Ill. L. Rev. 355, 357; Nard, ‘A Theory of Claim Interpretation’, 14 Harv. J.L. & Tech. 1, 82 (2000); Rai, ‘Engaging Facts and Policy: A Multi-Institutional Approach to Patent System Reform’, 103 Colum. L. Rev. 1040 (2003); Rai, ‘Regulating Scientific Research: Intellectual Property Rights and the Norms of Science’, 94 NW. U.L. Rev. 77, 79 (1999).

14) Johnson Worldwide Associates v Zebco Corp., 175 F.3d 985, at 989 to 990 (Fed. Cir. 1999).

15) Ibid.

16) Ibid.

17) Amgen, 339 F.Supp. 2d at 224. The Federal Circuit noted that ‘[i]f the claim term "therapeutically effective" encompasses the patient responses, as it appears to us it does, then the Goldwasser study may constitute invalidating prior art ….’

18) Ibid.

19) Ibid. at 228.

20) Ibid. at 229.

21) Ibid. at 232.

21) Ibid. at 232.

22) Ibid.

23) The District Court found that the claims themselves provided no basis to alter the ordinary meaning of ‘therapeutically effective’.
24) Ibid. at 240 to 241.

25) Ibid. at 241.

26) Ibid. at 245 to 246.

27) Ibid. at 246.

28) Claim 4 of the ‘698 patent recites: A process for the production of a glycosylated erythropoietin polypeptide having the in vivo biological property of causing bone marrow cells to increase production of reticulocytes and red blood cells comprising the steps of: (a) growing, under suitable nutrient conditions, vertebrate cells comprising promoter DNA, other than human erythropoietin promoter DNA, operatively linked to DNA encoding the mature erythropoietin amino acid sequence of FIG. 6; and (b) isolating said glycosylated erythropoietin polypeptide expressed by said cells.

Claim 6 of the ‘698 patent recites:

A process for the production of a glycosylated erythropoietin polypeptide having the in vivo biological property of causing bone marrow cells to increase production of reticulocytes and red blood cells comprising the steps of: (a) growing under suitable nutrient conditions, vertebrate cells comprising amplified DNA encoding the mature erythropoietin amino acid sequence of FIG. 6; and (b) isolating said glycosylated erythropoietin polypeptide expressed by said cells. (emphasis added)

29) Ibid. at 249 to 250.

30) Ibid. at 251.

31) Upon remand, the District Court considered whether TKT infringed process Claims 4, 5, 6, 7, 8, and 9 of the ‘698 patent. Claims 4 and 6 are independent. Claims 5, 7, 8, and 9 are dependent claims. See Note 28 above for the text of independent claims 4 and 6. Claims 4 and 6 recite a process for the production of EPO in vertebrate cells using ‘DNA encoding the mature erythropoietin amino acid sequence of Fig. 6’. Based on the District Court’s interpretation of this phrase, it found that TKT’s process literally infringed these claims.

32) Del Mar Avionics, Inc. v Quinton Instrument Co, 836 F.2d 1320, 1325 (Fed. Cir. 1987).

33) Wang and Wang, ‘The Verification Flow Chart of Patent Infringement’, 86 J. Pat. & Trademark Off. Soc’y 74, 78 (2004).

34) For example, homologous recombination, different promoters, splice sites, leader sequences, and methods of growing the cells: Ibid. at 296 to 300.

35) Ibid.at 291.

36) [1996] RPC 76, 82.

37) The test established by the EPO’s Technical Board of Appeal in International Flavors & Fragrances, Inc [1984] OJ EPO 309.

38) In re Thorpe, 777 F.2d 695 (Fed. Cir. 1985).

39) [1997] RPC 1 at 48 to 49.

40) Paragraph 112.

41) Paragraph 114.

42) ‘Enablement’ is the US term analogous in concept to the UK term of ‘insufficiency’.

43) In re Wright , 999 F.2d 1557, 1561 (Fed. Cir. 1991).

44) Amgen, 339 F.Supp.2d at 277.

45) Ibid.

46) 559 F.2d 595, 606 (CCPA 1977).

47) 315 F.3d 1335 (Fed. Cir. 2003).

48) Amgen, 33 F.Supp. 2d at 277.

49) Ibid. at 279.

50) Ibid. at 279.

51) Ibid.

52) Ibid. at 263.

53) Exxon Research and Eng’g Co. v United States, 265 F.3d 1371, 1375 (Fed. Cir. 2001).

54) See, for example, Guang Ming Whitley, ‘A Patent Doctrine without Bounds: The ‘Extended’ Written Description Requirement’, 71 U. Chi. L. Rev. 617 (2004) (cited at Amgen , 339 F.Supp. 2d at 265).

55) 214 F.3d 1342, 1346.

56) Amgen, 339 F.Supp.2d at 266, citing to In re Hogan , 559 F.2d 595 (CCPA 1977), and In re Koller, 613 F.2d 819, 825 (CCPA 1980).

57) Amgen , 339 F.Supp.2d at 267. The District Court does note that determination of the written description issue on the second issue was more ‘squirrelly’ and presumably a closer call than the first: ibid.

58) Ibid. at 270.

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