Regeneron v Kymab – a general principle or a series of products?

The UK Supreme Court’s ruling in the Regeneron v Kymab dispute marks an important moment in UK patent litigation. It is not often that patent cases get this far. The UK’s top court has once again grasped the slippery concept of insufficiency, coming down, this time, against the patentee (the patent owner).

Research at the forefront of biotechnology can lead to breakthroughs that open up a new field or overcome a really difficult problem. An innovator making an advance of this kind will often want to obtain broad patent coverage so that it can benefit when others use the technology commercially. But broad patent coverage can lead to its own problems. In the UK and Europe, broad patent claims can trip up on the “sufficiency” hurdle. In essence, this happens when the technical disclosure provided in the patent is not clear and complete enough to enable others to carry out the invention themselves, or at least, not across the whole breadth of the claimed invention.

The monopoly-for-disclosure bargain

A patent provides a powerful monopoly – 20 years of exclusive rights. In exchange, the patentee is expected to publish details of the invention so that others can make use of it experimentally, under licence or commercially after the patent expires. Where there are broad claims, a challenger can argue that the information, experimental details and examples disclosed in the patent are inadequate to fulfil this obligation – the patent is “insufficient”.

In this case, the judge at first instance decided that the information disclosed in the patent was not enough to meet the required standard, the Court of Appeal decided that it was and the Supreme Court (on a majority of four to one) decided that it was not.

Both the Court of Appeal and the Supreme Court focused on European Patent Office case law, as indeed they should under the requirements of the European Patent Convention. The courts were applying the same tests (with some differences of nuance and emphasis) and so how did they reach such different conclusions?

A difficult case

Admittedly, this is a very difficult example. Regeneron had addressed an intractable problem – how to make antibodies in mice using a combination of human and mouse antibody genes. The challenge was to achieve both a good immune reaction in the mice (needing mouse characteristics) and to produce useful antibodies with the necessary “human” characteristics. Regeneron’s patent disclosure went some way towards solving the problem. It disclosed a “reverse chimeric locus” including human variable regions and mouse constant regions.

However, making a full range of useful humanised antibodies required a lot of additional work.  As is often the case in biotechnology, making a conceptual advance may be helpful, but implementing the concept to produce a useful product or therapy often involves a huge amount of additional research, refinement and further innovation. How much must a patentee do in order to achieve broad protection?

Technical contribution or the full range of products?

The Court of Appeal focused on the technical contribution they considered the patentee to have made. Regeneron’s approach, the evidence explained, had become the “gold standard” for in vivo antibody production. Their emphasis was on the idea that a patentee is entitled to fair protection having regard to the nature and character of the invention it has described.

The Supreme Court (well, four out of five judges) concluded that the Court of Appeal was wrong. They focused on the need to enable the skilled team to make substantially all of the types or embodiments within the scope of the claim. In their view, this was necessary to tie together the breadth of the claim with the contribution to the field. The patent enabled the production of some of the claimed products, but certainly not the bulk of them, and not the most useful ones.

The Supreme Court’s analysis emphasised the fact that the relevant patent claim was to a collection of products (i.e. genetically modified mice). This focus on products was picked up by the dissenting judge as the key reason for the divergence from the Court of Appeal.

Some have queried whether the Supreme Court is out of line with the European Patent Office’s approach. This is the UK’s highest court, however. Until any different position is adopted by the same court, this approach will be the one that must be applied in UK litigation.

Take away points

The Supreme Court’s ruling is likely to receive a mixed reaction from research-based life sciences companies. There may be concerns that new and ground-breaking approaches may not be able to secure the strong patent cover they deserve. Being restricted to only those versions of the invention disclosed in the patent specification may give limited protection.

In our view, however, the ruling is to be welcomed.

Tying up a fast-moving field with a 20-year monopoly can substantially suppress innovation. Competitors who are trying to develop their own approaches in ways that may owe little or nothing to the disclosure in the patent can find themselves threatened with costly and time-consuming litigation.

Applicants for patents, in the UK at least, will need to be wary of relying on what they might see as a general principle. Broad claims will need more examples and data to back them up.

Our content explained

Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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