Patents: meaning of enablement in anticipation by prior art

By Audrey Horton


The Patents Court has considered enablement in relation to anticipation of a claimed monoclonal antibody invention by prior art, and held the patent was invalid for lack of novelty; it was also obvious for lack of technical contribution, and insufficient for ambiguity.


An invention is new if it does not form part of the state of the art. The state of the art comprises everything made available to the public by means of a written or oral description, by use, or in any other way, before the date of filing of a European patent application (Article 54, European Patent Convention) (EPC).
In determining whether a patent claim lacked novelty over the prior art, the House of lords has held there were two separate requirements: disclosure and enablement (Synthon BV v SmithKline Beecham plc [2005] UKHL 59).

For a product which was on public sale to form part of the state of the art, it must be possible for the skilled person to reproduce it without undue burden (Enlarged Board of Appeal in G 1/92 Availability to the Public ).

Where a technical test is required to find out if a product or process is within the claim or not, if the skilled person could not know whether they were carrying out the right test, then the claim would be ambiguous and therefore insufficient Unwired Planet v Huawei [2016] EWHC 576)


T's product was a formulation of a monoclonal antibody, approved for the treatment of ulcerative colitis and Crohn's disease.

R claimed that T's product infringed R's patent. 

T denied infringement and claimed R's patent was invalid and should be revoked.R argued that for there to be anticipation what had to be enabled was the very thing disclosed in the prior art. T disagreed and argued, relying on Synthon, that as long as the prior art enabled the skilled person to produce something within the claim, the claim would be anticipated. 


The court held that T's product infringed R's patent, but that R's patent was invalid for lack of novelty, lack of technical contribution and insufficiency.

The purpose of the law of novelty was to prevent the state of the art from being patented again. The fact that other characteristics of a product could not be determined or reproduced did not suddenly mean that no information about the composition at all had been put into the state of the art by the prior use. It would be different if the inability to determine a feature of the product or the inability to reproduce it prevented the skilled person from making their own product at all. However, if the feature which could not be reproduced had nothing to do with the invention and did not prevent a skilled person from making something which, from their point of view, was the product of the prior art for all practical purposes, there was no reason why its absence was relevant to enablement. 

Synthon made it clear that the requirement of enablement was that whatever had been disclosed must be something the skilled person could use to produce a practical result. In the case of a prior use, as long as the information the skilled person could obtain by analysing the old product was enough to enable the skilled person to put it to practical use by making their own version of that product, that second version was part of the state of the art and a patent claim which covered it would lack novelty. The fact this second version was not identical with the old product in every detail would not matter as long as those differences did not take it outside the claim. If the skilled person could not make their own version of the old product at all then the claim would be novel.

If the skilled person could analyse the old product to their satisfaction and make their own second product based on that information which to the skilled person was identical, a later patent should not be able to claim the product.

Here, R's patent product claims were not claims to a simple chemical compound, but rather to populations of antibodies. When considered as a whole, these fell within the claim, even though some individual antibodies did not. It could not be the case that a prior antibody product, which was a population, was incapable of being part of the state of the art because there would always be a level of detail at which one could distinguish between the old product and the second product. The relevant place to draw the line was the claimed features. The same approach would apply to the disclosure of prior art documents.

It would be different if what was enabled by the prior disclosure did not inevitably fall within the later claim. Then the question of obviousness would arise. A claim would lack novelty as long as the prior art enabled the skilled person to produce something within the claim, that is provided there was enablement of whatever was disclosed in the prior art.

Additionally, R's patent was invalid on the ground of obviousness for lack of technical contribution plausibly demonstrated across the breadth of the claim. A patent monopoly should correspond to the technical contribution in the art, and R's patent was not an advance over the existing body of scientific knowledge.
R's patent was also invalid for insufficiency because of ambiguity. There were two different machines the skilled person looking at the patent could use to measure the relevant claim element. Depending on which machine was used, the result could either fall inside or outside the claim. This ambiguity was not of a kind which revealed an unclear boundary at the edge of the claim, it was truly ambiguous and invalid.


This decision is a useful analysis of the complex law relating to anticipation, and what amounts to an enabling disclosure. The key question is whether, if the skilled person attempted to put into effect a disclosure from the prior art, would they make something that fell within the claims of the patent. If so, there would be enablement. It would not matter that the skilled person's creation would not reproduce exactly the product or process described in the prior art. Each piece of prior art here was an anticipating disclosure, and they were enabled: the skilled team would not be able to make exactly the same antibody as disclosed, but they could make their own version that fell within the claims of the patent.

Case: Takeda UK Ltd v F Hoffmann-La Roche AG [2019] EWHC 1911 (Pat)

First published in the September 2019 issue of PLC Magazine and reproduced with the kind permission of the publishers. Subscription enquiries 020 7202 1200.