The appeal in Biogen Inc. v Medeva Plc [1997] RPC 1  was the law lords' first opportunity to consider the validity of a patent for a product of genetic engineering. The patent in suit was an artificial molecule of deoxyribonucleic acid ("DNA") coded to induce production of hepatitis B antigens for use in diagnosis and production of a vaccine against the disease.  Sir Kenneth Murray of Edinburgh University found a way to make such molecules.  Biogen Inc. ("Biogen"), a Massachusetts company that Sir Kennth and other eminent molecular microbiologists had set up, applied for a British patent for the molecule on the 22nd December 1978 and a European patent based on the British application on the 21st December 1979. The principal claim was for:

"A recombinant DNA molecule characterized by a DNA sequence coding for a polypeptide or a fragment thereof displaying HBV antigen specificity, said DNA sequence being operatively linked to an expression control sequence in the recombinant DNA molecule and being expressed to produce a polypeptide displaying HBV antigen specificity when a suitable host cell transformed with said recombinant DNA molecule is cultured, the transformed host cell not producing any human serum proteins and any primate serum proteins other than the polypeptide displaying HBV antigen specificity."

Lord Hoffmann described the claim as to a product identified partly by the way in which it was made ("recombinant DNA molecule") and partly by what it did ("characterized by…" et cetera). A European patent was granted on the 11th July 1990, though it was subject to opposition (more like revocation) proceedings which were not concluded in its favour until the 28th July 1994.  Medeva Plc ("Medeva") developed and prepared to market a third generation hepatitis B vaccine by other techniques.

Biogen sued Medeva for infringing its patent in 1992 and Medeva counterclaimed for revocation of the patent. At first instance, Aldous J (as he then was) found that the patent was valid and infringed. His decision was reversed by the Court of Appeal on the ground that the matter disclosed in the specification did not support the invention, that Biogen was not entitled to claim priority from the date of application of the British patent and that the invention did not involve any inventive step (see Biogen Inc. v Medeva Plc [1995] FSR 1).  Hobhouse LJ, who delivered the judgment of the Court, doubted that the molecule was even an invention at all (see Biogen Inc v Medeva Plc [1995] FSR 4, 29-33).  The House of Lords put to one side the questions of what is or is not an invention and whether Sir Kenneth's work was obvious.  It dismissed the appeal on the ground that the claims were far too broad as there were other ways of producing recombinant DNA molecules.  Even though Sir Kenneth "had won a brilliant Napoleonic victory in cutting through the uncertainties which existed" it was not enough to justify a monopoly of the whole field. As Lord Hoffmann put it: at page 52:

  "The technical contribution made in such cases deserves to be recognized. But care is needed not to stifle further research and healthy competition by allowing the first person who has found a way of achieving an obviously desirable goal to monopolize every other way of doing so."

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