On 20 January 2021, Mr Justice Birss handed down judgment in Illumina v Latvia MGI Tech & Ors.1

In a lengthy judgment reaching over 500 paragraphs, Birss J found four of Illumina's patents to be valid and infringed by various MGI sequencing systems, with a fifth patent held to be infringed but invalid for obviousness.

The decision provides the first detailed judicial consideration of the Supreme Court's decision in Regeneron v Kymab and addresses a number of interesting points of patent law arising from that decision. In addition to recasting the principles relating to enablement laid down in Regeneron in more general terms that will apply equally to product and process claims, Birss J provides interesting commentary on what is meant by the "relevant range" over which a patent claim must be enabled.

The Judge began with a review of the eight principles of enablement summarised by Lord Briggs at paragraph 56 of the Regeneron decision. He considered that the reasoning in Regeneron did not only apply to product claims and was also relevant to the process claims in issue. However, he warned that care needed to be taken when transposing some of those principles to other contexts and went on to recast a number of Lord Briggs' principles in terms that are generally applicable to all forms of claim.

He also considered the interaction between the principles laid down in Regeneron and a number of other principles relevant to insufficiency. Having reviewed the authorities on the issue, Birss J held that a claim which defines a feature or component of the invention in structural or functional terms will not necessarily be insufficient simply because the structural or functional definition encompasses embodiments that would not work. Such definitions are permissible as long as they do not create an undue burden for the skilled person in determining suitable candidates for putting the invention into effect. The Judge also rejected MGI's contention that, following Regeneron, claims that contain functional definitions will necessarily be insufficient because they inevitably cover things that have not yet been invented, noting that such an absolutist approach would represent a radical change to the law for no discernible benefit to the public.

Birss J also provided useful guidance on how a "relevant" range, which would engage the principles in Regeneron, can be distinguished from an irrelevant range. In his view, "relevance" in the Regeneron sense "depends on examining all the circumstances, and depend not simply on the invention (that is to say the claim as drafted) but also on what I can only think of calling the essence or core of that invention (closely related to the technical contribution and/or inventive concept)".

Thus in Regeneron, Birss J considered that the range of different amounts of segments incorporated in each mouse was clearly relevant to the essence of the invention - generating high antibody diversity. In applying this test to other cases Birss J added that one might need to examine the essence of the invention as well as the claim language itself, and that it would be an "unusual case" if ordinary descriptive or functional language would be viewed as a "relevant" range in the Regeneron sense.

With the above in mind, Birss J went on to summarise the relevant principles at paragraph 279 of the judgment, as follows:

i)          When examining any aspect of claim scope for the purposes of the enablement it is necessary to distinguish between ranges relevant in the Regeneronsense and other ranges. 

ii)         For ranges relevant in the Regeneronsense, to be sufficient, there must be enablement across the whole scope of the claim within that relevant range (subject to de minimis exceptions) at the relevant date.  If a type or embodiment within such a range is not enabled at that date then the fact it could be made later, as a result of further developments not enabled by the patent, even though it never could have been made without the invention, will not save the claim from insufficiency.

iii)        Not all claims will necessarily contain a range relevant in the Regeneron sense but if they do, then this principle applies to that range.

iv)        An example of an other range, not relevant in the Regeneronsense, will be a descriptive feature in a claim (whether structural or functional) which can cover a variety of things, but for which that variety does not significantly affect the value or utility of the claimed product or process in achieving its relevant purpose.  The relevant purpose is judged in all the circumstances, starting from the terms of the claim itself but also, where appropriate, by reference to the essence or core of the invention.

v)         For a claim feature which amounts to a range in this other sense, the skilled person must still be able to make a suitable selection, without undue burden, in order for the claim to be sufficiently disclosed.  However provided that is so at the relevant date, such a claim feature will not be insufficient simply because it is capable of also covering within its scope things which had not been invented at that relevant date.

vi)        When examining enablement of any kind, the test is always about what the skilled person is able to do without undue burden.  The patentee is entitled to expect that the skilled person, in seeking to make the invention work, will exercise that skill.  If need be that exercise will involve testing and experiments, as long as it is not unduly burdensome."

It will be interesting to follow how this case progresses and, if appealed, whether the higher courts will endorse Birss J's views on what will constitute a "relevant range" in the Regeneron sense. Whilst reference to the "essence of the invention" may ameliorate some of the potential negative effects of the Supreme Court's decision in Regeneron, it is not clear that Birss J's approach can be reconciled with the facts of the Regeneron case itself. The essence of the invention in Regeneron was ostensibly not the diversity of antibodies that could be produced by the claimed mice, but that those mice would not suffer from the "immunological sickness" that afflicted the mice of the prior art (see, for example, Lord Briggs' comments in paragraph 20 of Regeneron).

1 [2021] EWHC 57 Pat

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