Patents - The Supreme Court's Judgment in Regeneron Pharmaceuticals Inc v Kymab Ltd

Author George Shuklib Licence CC NY-SA 1.0 Source Wikipedia Mouse 

Jane Lambert
Supreme Court (Lords Reed, Hodge, Briggs and Sales and Lady Black) Regeneron Pharmaceuticals Inc v Kymab Ltd [2020] UKSC 27 (24 June 2020)

This was an appeal from the Court of Appeal's judgment in Regeneron Pharmaceuticals, Inc v Kymab Ltd and another [2018] EWCA Civ 671 (28 March 2018).  The Supreme Court reversed the judgment of the Court of Appeal to allow the appeal of  Regereron Pharmaceuticals Inc, ("Regeneron") against the judgment of Mr Justice Henry Carr in Regeneron Pharmaceuticals Inc v Kymab Ltd and another [2016] EWHC 87 (Pat) (1 Feb 2016).  Mr Justice Henry Carr had dismissed Regeneron's action for infringement of European Patent (UK) No. 1 360 287 ("the 287 Patent") and European Patent (UK) No. 2 264 163 ("the 163 Patent") and allowed a counterclaim by Kymab Ltd ("Kymab") for revocation of those patents.

The Invention

A press summary and video issued by the Supreme Court described the invention for which the 287 and 163 patents had been granted as a mouse.  That is an oversimplification if not misleading because nobody can make a mouse or any other animal for that matter. The invention used the mouse's body to make antibodies for treating human disease.  It did that by replacing part of a murine gene with part of a human one. The title of both patents was "Methods of modifying eukaryotic cells" which indicated a method rather than a product.  Perhaps the reason for describing the invention  as a product is that claim 1 of the 163 Patent claimed:

“A transgenic mouse that produces hybrid antibodies containing human variable regions and mouse constant regions, wherein said mouse comprises an in situ replacement of mouse VDJ regions with human VDJ regions at a murine chromosomal immunoglobulin heavy chain locus and an in situ replacement of mouse VJ regions with human VJ regions at a murine chromosomal immunoglobulin light chain locus.”

S.125 (1) provides that an invention for which a patent has been granted shall unless the context otherwise requires, be taken to be that specified in a claim of the specification.

The Dispute

Regeneron sued Keymab for engineering a mouse known as a Keymouse with a full set of human antibody genes that could produce an enormous range of human antibodies. The action came on before Mr Justice Henry Carr who found that the Keymouse fell within the claims of the patents but the patents were invalid for insufficiency.

The Issue

Art 83 of the European Patent Convention ("EPC") requires an applicant for a European patent to "disclose the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art." One of the grounds for revoking a European patent is that it does not disclose the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art (see art 138 (1) (b) EPC). 

Mr Justice Heny Carr held that "at the priority date, the skilled person would not have been able to perform the invention over the whole area claimed without undue burden and without needing inventive skill" (paragraph 326 (iv) of his judgment). Lady Justice Arden and Lords Justices Kitchin and Floyd disagreed.  Lord Justice Kitchin said at [265] of his judgement:

"the law does not require a patentee to enable each and every embodiment of a claimed invention. As the authorities recognise, a claim may encompass inventive improvements of what is described and a specification is not insufficient merely because it does not enable the person skilled in the art to make every such invention. It is important, however, that any such improvement is still a way of working the original invention. In this case we have no doubt that this is the case: there is no mouse falling within the scope of claim 1 of the 163 patent which does not embody the reverse chimeric locus and enjoy the benefits it brings."

The question for the Supreme Court was which of those views was right.

The Basic Principle

Delivering judgment on behalf of the majority of the Supreme Court Lord Briggs said at paragraph [24] that the duty of disclosure under art 83 does not have to enable the product to be made by any member of the public, or solely by using the teaching in the patent:

"The law creates, distinctly for each patent under scrutiny, a notional skilled person or (as here) skilled team who must be enabled to make the product by the combination of the teaching in the patent, the general technical knowledge available at the priority date, and a reasonable (ie not burdensome) element of experimentation. But the skilled person is not expected to be inventive or even, as is sometimes said, imaginative: see Rockwater Ltd v Technip France SA [2004] RPC 46, paras 7 and 10 per Jacob LJ."

Lord Briggs set out the competing contentions at paragraphs [25] and [27]:

"Starting to apply those basic principles to the question before the court, is disclosure 'sufficient' if the teaching in the patent enables only some but not all of the products within the claimed range to be made? Subject to de minimis exceptions, the instinctive answer would be: surely not. If in principle the patentee should be entitled to a monopoly only over the making of a product which the teaching in the patent enables the skilled person to make, why should not the same principle apply to every product type within the relevant range for which a monopoly is sought? The essential patent bargain is not satisfied in relation to products in that part of the range which cannot be made, using the teaching in the patent."

He said at [27]:

"The Court of Appeal did not doubt this analysis as a general rule, but concluded that it would defeat the implementation of the essential patent bargain if applied to a case in which the invention amounted to a principle of general application, which would yield the relevant increase in efficiency or usefulness across a range of potential product types if they incorporated the invention, as and when they could be made, even if only a few could be made as at the priority date by using the teaching in the patent. In bare outline their reasoning was as follows. The patent bargain requires that the reward given to the patentee should be commensurate with the contribution which the invention makes to the art. An invention which consists of a new generally applicable principle may contribute to the art by its use, not only in products which can currently be made, but equally in products which will only be capable of being made in the future, after further inventive research and development. To limit the patentee strictly to a monopoly over the products which can immediately be made would be to deprive the patentee of any reward for the public benefit which will be derived from the use of that same invention in future types of product. In a fast-moving field, where new products quickly outperform their predecessors so as to render them obsolete, the reward of a monopoly limited to those immediately capable of being made would be short-lived and illusory. Accordingly the invention should be regarded as sufficiently enabled across the range if it can be seen that it will in due course benefit all products in the range, provided that, as at the priority date, the teaching in the patent enables at least one type to be made immediately. Since the Reverse Chimeric Locus would be likely to deal with murine immunological sickness in mice whose genomes were fitted with “all or any” amount of the human variable segments, up to and including the whole of the human variable region, its invention was one of those principles of general application which should be regarded as enabled across the whole range contemplated by Claim 1. A monopoly over the making and exploitation of the whole range would correspond with the contribution made by the Reverse Chimeric Locus to the art."

Analysis

Between paragraphs [30] and [55], Lord Briggs reviewed the authorities of the English courts and the European Patent Office Broads of Appeal. He set out the principles that he had discerned from that review at [56]:

"i) The requirement of sufficiency imposed by article 83 of the EPC exists to ensure that the extent of the monopoly conferred by the patent corresponds with the extent of the contribution which it makes to the art.
ii) In the case of a product claim, the contribution to the art is the ability of the skilled person to make the product itself, rather than (if different) the invention.
iii) Patentees are free to choose how widely to frame the range of products for which they claim protection. But they need to ensure that they make no broader claim than is enabled by their disclosure.
iv) The disclosure required of the patentee is such as will, coupled with the common general knowledge existing as at the priority date, be sufficient to enable the skilled person to make substantially all the types or embodiments of products within the scope of the claim. That is what, in the context of a product claim, enablement means.
v) A claim which seeks to protect products which cannot be made by the skilled person using the disclosure in the patent will, subject to de minimis or wholly irrelevant exceptions, be bound to exceed the contribution to the art made by the patent, measured as it must be at the priority date.
vi) This does not mean that the patentee has to demonstrate in the disclosure that every embodiment within the scope of the claim has been tried, tested and proved to have been enabled to be made. Patentees may rely, if they can, upon a principle of general application if it would appear reasonably likely to enable the whole range of products within the scope of the claim to be made. But they take the risk, if challenged, that the supposed general principle will be proved at trial not in fact to enable a significant, relevant, part of the claimed range to be made, as at the priority date.
vii) Nor will a claim which in substance passes the sufficiency test be defeated by dividing the product claim into a range denominated by some wholly irrelevant factor, such as the length of a mouse’s tail. The requirement to show enablement across the whole scope of the claim applies only across a relevant range. Put broadly, the range will be relevant if it is denominated by reference to a variable which significantly affects the value or utility of the product in achieving the purpose for which it is to be made.
viii) Enablement across the scope of a product claim is not established merely by showing that all products within the relevant range will, if and when they can be made, deliver the same general benefit intended to be generated by the invention, regardless how valuable and ground-breaking that invention may prove to be."

Applying those Principles

In Lord Briggs's view, the application of those principles to the facts of the case showed clearly that claim 1 failed for insufficiency. At the priority date the disclosure of the two patents, coupled with the common general knowledge, enabled skilled addressees to engineer mice to generate only a limited number of antibodies. He concluded:

"Thus the claim to a monopoly over the whole of that range went far beyond the contribution which the product made to the art at the priority date, precisely because mice at the more valuable end of the range could not be made, using the disclosure in the patents."

His lordship criticized the Court of Appeal's analysis at [58] quite severely.  In his view, that Court did not apply the law correctly for the two reasons. First, the monopoly granted must be commensurate to the contribution to the art because patents are about products and processes and not about ideas. Secondly, upholding the claimant's monopoly would have prevented further development of the technology.  Lord Briggs did not regard the Court of Appeal's decision as a legitimate development of the law.  It would have undermined one of the basic principles of patent law and tilted the balanced between public and patentees in favour of patentees in a way not warranted by the EPC.

Lady Black's Dissenting Judgment

Lady Black analysed the differences between the Court of Appeal' approach and that of the majority of the Supreme Court and those between the majority's approach and her own.  There appeared to be no differences in identifying the applicable legal principles. Differences lay only in the application of those principles.  The majority took the view that the technical contribution lay in the range of antibodies that could be produced by this technique whereas for her it was the creation of mechanisms that would generate antibodies that would not be rejected by humans but would not render mice immunologically sick.

Understanding the Judgment
The appeal was heard on 11 and 12 Feb 2020 and videos of the proceedings before the Justices can be seen on the Supreme Court's website (morning and afternoon 11 Feb and morning and afternoon 12 Feb). I have already inserted links to the judgments in the Supreme Court and the courts below, the press summary and Lord Briggs's video.

Comment
The judgment that the Supreme Court overturned was delivered by Lord Kitchin (as he now is) and Lord  Justice Floyd who spent a lifetime at the intellectual property bar and sat as judges of the Patents Court.  The third member of that bench (Lady Arden as she now is) had a more general practice at the chancery bar but she heard IP cases when she was a High Court judge and her judgments have always been considered sound. To the best of my knowledge and belief, none of the Justices practised IP law at the bar or sat regularly on the Intellectual Property List.  Treating the invention as a product rather than a method and talking about making mice must have been confusing, I have to say that Lady Black's reasoning is crystal clear whereas I had to read some passages of the majority judgment several times before I could say that I understood them.

Contact
Anyone wishing to discuss this article or the appeal should call my clerk on 07986 948267 or send me a message through my contact page.