You are here: Home > News > Sufficiency and chocolate teapots: Illumina v MGI

Sufficiency and chocolate teapots: Illumina v MGI

9 February 2021

Last June saw the UK Supreme Court in Regeneron v Kymab overturn a decision from the Court of Appeal on sufficiency. They raised the bar to require that the disclosure of a patent supports substantially every embodiment of the claims (for our previous report of this case, see here). We have now seen the first application of these sufficiency principles in Illumina v MGI, a decision handed down by the UK High Court on 20 January 2021 (see here).

In the case in question, the High Court 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 High Court reviewed the principles of sufficiency laid down in Regeneron and held that they not only apply to product claims (as considered in Regeneron) but also to process claims, such as those at issue in Illumina.

Further guidance was provided on the concept of a “relevant range” in which it is required to show enablement across the scope of the claim, as formulated in Regeneron.

The Judge considered a hypothetical patent claiming a new type of teapot which was inventive and useful because it had a special spout shaped to prevent dripping. The patent claim to the teapot would include features of the shape of the spout, but may not limit the teapot to any particular material. Consequently, the claim would include embodiments where the teapot would be functional (e.g. a teapot made from china) and embodiments where the teapot would be non-functional (e.g. a teapot made from chocolate). Applying Regeneron, the material of the teapot does not relate to the core inventive concept underlying the technical contribution of the non-dripping feature, and therefore a non-dripping teapot does not need to be enabled over the entire scope of possible teapot materials.

Turning to Illumina, MGI argued that the scope of the claims included nucleotides that could be modified in ways which would prevent their use in the claimed sequencing method. MGI further argued that the claims covered methods of sequencing with unspecified read-lengths, whilst the specification only included examples of short reads. The Judge rejected both of these arguments as effectively analogous to chocolate teapots that did not relate to the essence of the invention and were not “relevant ranges” according to Regeneron. What was important was that the skilled person could, without undue burden, disregard the impractical modified nucleotides in favour of functional embodiments at the priority date of the invention.

This decision highlights that a crucial part of sufficiency analysis is determining which elements of the claim relate to the essence of the invention and are a “relevant range” in the Regeneron sense. For the relevant range to be sufficient, there must be enablement across the whole scope of the claim within that relevant range at the priority date of the invention. This should be taken into account when drafting patent claims and attacking patents on the ground of insufficiency.


Dr Heather West
Life Sciences & Chemistry group

This publication is a general summary of the law. It should not replace legal advice tailored to your specific circumstances.

© Withers & Rogers LLP February 2021