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Infringement and validity

Posted on 13 March 2020


The Supreme Court’s 2017 decision in Actavis v Eli Lilly introduced a doctrine of equivalents (DOE) into UK law. In the two years that have followed, the new approach to claim construction has been a matter of considerable debate (see in particular, the Court of Appeal’s decision in Icescape v Ice-World discussed in our 2018 Review). In 2019, were a number of cases that considered its application, and which found infringement on the basis of the DOE, or would have done if the patent in question had been found valid. These include: Regen v Estar (in a claim relating to numerical limitations), Marflow v Cassellie, Lilly v Genentech (albeit the patent was found invalid), Technetix v Teleste (and in separate proceedings between the same parties: Technetix v Teleste - although in both cases the patent was found invalid), Mishan v Hozelock (though the patent was again found invalid) and Excel-Eucan v Source Vagabond Systems. This is clearly a trend that will continue.

A new UK defence to patent infringement? Not quite yet…

However, in Technetix B.V. v Teleste Limited, the Intellectual Property Enterprise Court might have opened the door to a new so-called ‘Formstein’ defence to patent infringement in such cases. Admittedly, the judge’s comments were non-binding – since the patent in suit was held invalid for want of both novelty and inventive step – but the decision sets up the opportunity to apply this novel defence in future actions. 

Of particular relevance in Technetix was the question of how the Court would view an infringement claim based on equivalents, in a situation where the allegedly infringing equivalent was obvious (and therefore not patentable) at the filing date of the patent in suit.

Although the judge concluded that the Patent was invalid, he considered how the expanded scope of claim protection afforded by the relatively newly adopted DOE could impact infringement analyses. Teleste’s position was one that has been tried and tested in Germany - the ‘Formstein’ defence. This means that, even if its product fell within the scope of the claim, it would do so only as an equivalent, and there should be a defence to infringement because that equivalent lacked novelty or an inventive step over the prior art.

Whilst acknowledging that no standalone defence of this nature exists in the UK, the judge stated that it has long been a basic principle of UK patent law that a patentee cannot prevent a person from doing what he or she has been lawfully entitled to do before the grant of any asserted patent. He explicitly acknowledged that English law might adopt a ‘Formstein’ defence in the future. Not only did he proceed to analyse Teleste’s alleged infringement on the basis that such a defence already exists, he found that, if it did,Teleste would be entitled to it.

It seems very likely that Formstein defences will increasingly form part of cases going forward.


2019 saw a high ratio of invalidity findings by the UK Courts, with all or the principal claims being held invalid in a significant number of cases, as demonstrated by the summary list below. Lack of inventive step was a feature in the vast majority of cases, with plausibility and Agrevo obviousness also commonly featuring. In contrast, classic insufficiency and added matter attacks were rarer.

All/principal claims held invalid

  • Actavis v Icos (Supreme Court)
  • SSH Communications v Sony (Court of Appeal)
  • Regen v Estar (Patents Court)
  • Garmin v Philips (Patents Court)
  • Lilly v Genentech (Patents Court)
  • Mishan v Hozelock (Patents Court)
  • Allergan v Aspire (Patents Court)
  • Technetix v Teleste x two decisions (IPEC)
  • Takeda v Roche (Patents Court)
  • Conversant v Huawei (Patents Court)
  • Conversant v Apple (Patents Court)
  • Adolf Nissen Electrobau v Horizont Group (IPEC)
  • Philips v Asustek (one patent) (Court of Appeal)

Principal claims held valid

  • Clearswift v Glasswell (IPEC)
  • Marflow v Casselie (IPEC)
  • Illumina v TDL (Patents Court)
  • L’Oréal v Liqwd & Olaplex (amended claim) (Court of Appeal)
  • Philips v Asustek (two patents) (Court of Appeal)

Supreme Court upholds obviousness finding against tadalafil dosage patent

Whether or not a distinct dosage regime of a known compound can be inventive is an important policy question. In its decision in Actavis v ICOS, the Supreme Court upheld the finding that ICOS’ patent (licensed to Eli Lilly) relating to the use of tadalafil - sold under the brand name Cialis - in a dosage form for the treatment of erectile dysfunction, was invalid for lack of an inventive step over a prior art patent disclosing the use of the drug to treat ED.

The skilled team had embarked on familiar and routine testing of tadalafil to establish the appropriate dosage regime in the light of the prior art teaching. It was obvious for them to embark on that testing and carry out routine tests until the appropriate dose was identified, including completing dose-ranging studies as part of Phase IIb testing, which led to the claimed dose range. The fact that the dose identified (5mg/daily) as effective for treatment of ED, whilst having reduced side effects, was a surprising outcome did not mean that identifying that dose was inventive.

However, the Supreme Court reiterated that it is not the law that investigations into appropriate dosage regimes cannot yield patentable inventions, or that there are policy reasons which would justify such a blanket approach. That said, the outcome in this case does demonstrate that intensive and expensive research leading to an unexpected result may not, in all circumstances, justify a patent where the work carried out is routine, and alongside other potentially relevant factors.

In his judgment, Lord Hodge identified the following non-exhaustive factors as being potentially relevant in each case (the weight of each factor will vary potentially depending upon the circumstances):

  • Whether at the priority date something was ‘obvious to try’: was it obvious to undertake a specific piece of research which had a reasonable or fair prospect of success?
  • The routine nature of the research and any established practice of following such research through to a particular point.
  • The burden and cost of the research programme.
  • The necessity for, and nature of, the value judgment the skilled team would have in the course of a testing programme.
  • The existence of alternative or multiple paths of research.
  • The motive of the skilled person: it is not enough that the skilled person could undertake a particular trial, but it could be asked whether in the circumstances they would have been motivated to do so.
  • The fact that the results are unexpected or surprising.
  • When addressing the statutory question of obviousness, hindsight, including knowledge of the invention, should be avoided.
  • Whether a feature of a claimed invention is an added benefit in a context in which the claimed innovation is obvious for another purpose.

The Supreme Court’s decision in ICOS was considered in Allergan v Aspire where Mr Justice Arnold (as he then was) noted that “the overall tenor of the judgment of Lord Hodge …is to confirm the approach which had previously been adopted by the courts to this question”. One might argue therefore that nothing has actually changed since Kitchin J’s (as he then was) decision in Generics v Lundbeck in 2007, where he had stressed that the question of obviousness must be considered on the facts of each case and that the “court must consider the weight to be attached to any particular factor in the light of all the relevant circumstances. These may include such matters as the motive to find a solution to the problem the patent addresses, the number and extent of the possible avenues of research, the effort involved in pursuing them and the expectation of success.” Given that, it arguably appears unnecessary for the ICOS case to have been put before the Supreme Court.

Hose patent invalid, but no prior use

A validity decision to note was Mishan v Hozelock which raised interesting questions as to prior use. The inventor had made prototypes of his expandable hose invention in his garden which was visible from the road. However, the Court concluded that separate disclosures on separate days could not be combined: the skilled person would not be motivated to return, as it “just looked like a man using a hose in his garden”. Further, and in any event, the use by the inventor was not even public use, i.e., he had not made the information available to the public. If anyone had tried to observe him working on his invention, he would have simply packed up and gone inside his house. The Patent was, however, invalid for lack of inventive step. The Court of Appeal will hear the appeal in this case in Summer 2020.

Takeda v Roche – What needs to be enabled by the prior art?

This issue was considered by Birss J in Takeda v Roche. In particular, he noted that, in the case of prior use, provided the information the skilled person can obtain by analysing the old product is enough to enable them to put it to practical use by making their own version of that product, that second version is part of the state of the art and a patent claim which covers it would lack novelty. Here, the fact that the skilled person’s own version of the product was not identical with the old product in every particular way did not matter provided those differences did not take it outside the claim. Further, if the skilled person cannot make their own version of the old product at all then the claim would be novel.

Court of Appeal clarifies approach to insufficiency

In Anan Kasei v Neo Chemicals, the Court of Appeal considered the approach to questions of insufficiency and how to delineate the ‘boundary’ of protection. Whilst the decision does not set out new principles, it does contain useful guidance. In particular, as Lewison LJ put it in his supporting judgment, a ‘fuzzy boundary’ to a claim is not the same as it being impossible to ascertain the limits of protection: “the boundary may be fuzzy, but it is still a boundary”. If, however, the Court is unable to ascertain the boundary, using all available interpretive tools, the conclusion will be that the specification does not disclose the invention clearly and completely enough for it to be performed by a person skilled in the art, and hence it is insufficient.

The Patent (owned by Anan Kasei, with Rhodia as exclusive licensee) related to ceric oxide (or ceria) and concerned a catalyst for purifying vehicle exhaust gases.The Patent has five product claims which relate to specific characteristics of a ceric oxide with a high surface area. Claim 1 was in the following terms:

A ceric oxide consisting essentially of a ceric oxide, and wherein said ceric oxide has a specific surface area of not smaller than 30.0 m2 /g when subjected to calcination at 900ºC for 5 hours”.

Claim 1 was therefore limited through the wording “consisting essentially” of a particular oxide. Neo argued that this made the Patent invalid as it gave rise to uncertainty. Further, Claim 1 was limited by the reference to a desirable physical characteristic for such an oxide, namely a high specific surface area, and that it remains the same after being subjected to a high temperature heating test. Neo argued that this meant the claim insufficiently described the invention.

The Court of Appeal noted the distinction in ‘patent jargon’ of a claim for a composition of matter which ‘consists’ of something and one which ‘comprises’ something. ‘Consisting’ will normally be taken to impose a requirement that nothing else is present, ‘comprising’ sets out a minimum requirement, meaning other things can be present.The Court of Appeal identified the words used in the Patent, i.e., ‘consisting essentially of ’, as a ‘hybrid’ of these two formulations. However, whilst the words might be thought to give rise to some uncertainty, in fact the skilled person would have regard to EPO practice to interpret such claims as meaning that, apart from the mandatory ingredient (here, ceric oxide), no other ingredients are present which materially affect the essential characteristics of the product.

Neo argued that the specification did not contain any direction or explanation as to the meaning of ‘consisting essentially of ceric oxide’, and that therefore the skilled person would be unable to implement the invention without undue burden or at all. The Court of Appeal disagreed.The Court also said it was inaccurate to describe this type of insufficiency argument as one focused  on ‘ambiguity’. Instead, the proper description was that it was an argument of ‘uncertainty’: in the leading Kirin Amgen case, for example, the relevant claim was not struck down for insufficiency as it was ambiguous, but because it was conceptually uncertain.

The Court also rejected a breadth of claim insufficiency attack.

Read more

In Lilly v Genentech, meanwhile, Arnold J in the Patents Court considered the Supreme Court’s decision in Warner-Lambert v Generics, discussed in in our 2018 Review. Genentech’s patent claimed an antibody which binds to IL-17A/F heterodimer to treat, inter alia, psoriasis. Arnold J referred to Lord Sumption’s judgment in Warner-Lambert and noted that plausibility depends upon the context: here, the case was concerned with a first medical use, not a second medical use. He concluded that the claim of efficacy against psoriasis was not plausibly disclosed in the patent and the claim was speculative. In other words, the outcome would have been the same regardless of Lord Sumption’s decision in Warner-Lambert. The appeal is listed to be heard in January 2021.

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