Biogen Inc. v Medeva Plc

A patent claim must correspond to the invention’s technical contribution. An enabling disclosure must permit the skilled person to perform the invention across the full breadth of the monopoly claimed. A general claim may be justified where the disclosure establishes a generally applicable principle. It is not justified where the patentee teaches only one way of obtaining a result but claims every way of doing so.

An earlier application supports a priority claim under the Patents Act 1977 only if it contains an enabling disclosure of the later claimed invention. The same relationship between disclosure and claim breadth governs sufficiency. Sufficiency is assessed at the application date; later developments in the art cannot cure an insufficient application.

Biogen Inc. v Medeva Plc concerned a European patent claiming recombinant DNA molecules and resulting polypeptides displaying hepatitis B virus antigen specificity. The patent was based on work in 1978 which had produced hepatitis B antigens by inserting large fragments of unsequenced viral DNA into bacterial cells.

Biogen sued Medeva for infringement after Medeva proposed to market a vaccine made using recombinant DNA technology and mammalian cells. Medeva counterclaimed for revocation. Aldous J held that the patent was entitled to the earlier priority date, was valid and had been infringed. The Court of Appeal allowed Medeva’s appeal, holding that the earlier application did not support the claims and that the patent was obvious and insufficient.

The central issue before the House was whether the earlier application contained an enabling disclosure broad enough to support claims covering every recombinant method of making the antigens.

1. Appeal dismissed unanimously. Lord Hoffmann delivered the leading speech. Lords Goff of Chieveley, Browne-Wilkinson and Slynn of Hadley agreed with his reasons, and Lord Mustill expressly agreed with both the conclusion and the reasons. The Court of Appeal’s order was affirmed, and Biogen was ordered to pay Medeva’s costs.

2. Per Lord Hoffmann, the court should ordinarily begin with the express conditions of patentability in section 1(1) of the Patents Act 1977. A separate inquiry into whether the subject matter is conceptually an “invention” will rarely be required. Lord Mustill added that a future case involving new technology might nevertheless require definitive consideration of that question.

3. Per Lord Hoffmann, the inventive concept must identify the problem overcome by the inventor, rather than merely state the desired result. The relevant concept was trying to express unsequenced eukaryotic DNA in a prokaryotic host. The commercial reasons for attempting an experiment and the perceived odds of success did not determine whether it involved an inventive step. The House assumed, without deciding, that the work was not obvious at the earlier date.

4. Per Lord Hoffmann, adopting the enabling-disclosure principle in Asahi Kasei Kogyo KK’s Application [1991] R.P.C. 485, “support” under section 5(2)(a), support and disclosure under section 14, and sufficiency under section 72(1)(c) share the same underlying concept. The specification must enable the invention across the full extent of the monopoly claimed. A generally applicable principle can justify general claims. Where the claim covers discrete methods or products, however, each must be enabled.

5. Per Lord Hoffmann, Professor Murray’s technical contribution was a way of making hepatitis B antigens while the viral genome remained unsequenced. It did not establish a general principle which later researchers had to use. The claims nevertheless covered every recombinant method, including methods based on sequencing and mammalian cells which owed nothing to that contribution. The monopoly therefore exceeded the disclosed technical contribution.

6. Per Lord Hoffmann, the earlier application did not support the claimed invention. The patent consequently lost the earlier priority date and was invalid because Biogen conceded that the claims were obvious by the filing date of the European application. The same excessive breadth also rendered the specification insufficient under section 72(1)(c), although that additional ground was unnecessary to the disposition.

7. Per Lord Hoffmann, sufficiency under section 72(1)(c) is assessed at the application date. Advances in the art between filing and publication cannot cure an insufficient disclosure. This conclusion was expressed as guidance because the patent was insufficient whichever date was used.

1. House of Lords: The appeal was dismissed unanimously. The Court of Appeal’s order was affirmed, with costs against Biogen.

2. Court of Appeal: The court allowed Medeva’s appeal from Aldous J. It held that the earlier application did not support the claimed invention, that the invention was obvious at the earlier date, and that the specification was insufficient.

3. High Court: Aldous J held that the earlier application supported the claims, that the patent was valid, and that Medeva had infringed it.