In his ruling in a case involving generic medicine manufacturers and a pharmaceutical firm, Lord Walker said that the generic manufacturers could only succeed in their case if patent law restricted the other side's patent to a new chemical's technical contribution, and if the technical contribution is the same as the inventive concept. He said this was not the case.
Pharmaceutical company Lundbeck created an anti-depressant medicine in 1972 whose patent has now run out. It then created an improved version through a chemical process. It was granted a patent on the improved version.
Generic manufacturers claimed that the developments in the new invention were not sufficient to merit protection. They applied to have the patent revoked. The High Court agreed with the generics' argument, but the Court of Appeal said that they were wrong and that the new invention deserved protection. The House of Lords agreed with that view.
Patents are only granted to new inventions that are different enough to existing inventions to merit protection. A patent must describe to someone who knows that area of science how to replicate the invention.
A patent can be revoked for 'insufficiency' if this disclosure is not detailed or accurate enough to allow a skilled person to reproduce the invented product or process.
The generic manufacturers said that Lundbeck's patent described only a limited technical contribution, because it disclosed only one method by which it made the improved drug. This method was the patent's inventive concept, they said, and this represented the patent's entire "technical contribution to the art".
Lord Walker rejected that argument, and said that the two terms do not mean the same thing.
"During the oral argument before your Lordships there was some discussion of whether 'inventive concept' means the same as 'technical contribution to the art'," he said in his ruling. "[The generics' lawyer] submitted in his reply that the two expressions…are synonymous."
"I do not think that this is quite right. The expressions are certainly connected, but I do not think it is helpful…to treat them as having precisely the same meaning. 'Inventive concept' is concerned with the identification of the core (or kernel, or essence) of the invention – the idea or principle, of more or less general application which entitles the inventor's achievement to be called inventive," said Lord Walker.
"The invention's technical contribution to the art is concerned with the evaluation of its inventive concept – how far forward has it carried the state of the art? The inventive concept and the technical contribution may command equal respect but that will not always be the case," he said.
Lord Neuberger said that publishing only one way of making something in a patent should not stop someone from claiming the monopoly on the product that results from that method.
"The product claim in the present case is valid. I appreciate that this means that, by finding one method of making a product, a person can obtain a monopoly for that product. However, that applies to any product claim," he said.
Lord Neuberger agreed with Lord Walker that it is a mistake to conflate the inventive step with the technical contribution to the art.
"There is a difference between the 'inventive step' or 'inventive concept', on the one hand, and the 'technical contribution to the art', on the other hand," he said. "When considering the validity of a simple product claim…it may be that concentrating on the identification of the inventive step rather than the technical contribution can lead to error."
"'Inventive step' suggests how something has been done, and, in the case of a product claim at any rate, one is primarily concerned with what has been allegedly invented, not how it has been done. On the other hand where the claim is for a process or includes a process, the issue of how the alleged invention has been achieved seems to be more in point."
There were no dissenting judges, and the generics' attempt to invalidate the patent on the grounds of insufficiency failed.