Supreme Court of Norway recognises doctrine of equivalents

On 2nd September 2009, the Supreme Court of Norway issued its keenly awaited ruling in the Donepezil appeal case (Eisai v Krka).

The court of first instance had granted an injunction banning Krka’s generic donepezil drug on the grounds that the method used to prepare the active ingredient, although different from that of Eisai’s patent, was the obvious method to use for a skilled person having knowledge of the patent and thus an equivalent falling under the scope of the patent.

Eisai’s patent was a so-called analogy method patent. These patents were granted until 1992, when Norway made it possible to grant product patents on pharmaceuticals. They were granted on known methods to prepare new compounds. The novelty and inventive step were in the compound, but protection was granted for process claims. There have been many cases in which the lower courts have tried to define the extent to which the doctrine of equivalents was applicable to this particular category of patents.

On appeal, the Borgarting Court of Appeal quashed the injunctive order, finding that the “obviousness” (in Norwegian, 'closeness') criterion which applies if a method is to be considered equivalent to another means that one method must be similar to the other, and that not any method that a skilled person would apply with a reasonable expectation of success would qualify as equivalent. That decision was appealed and finally the case made it all the way to the Supreme Court.

The Supreme Court, agreeing with the court of appeal, dismissed the appeal and stated:

"The point of departure is the patent claims and the method or methods described in them. It is the method that is protected, and as Krka has emphasised, the applicant has the opportunity to claim protection for all conceivable methods that he is capable of defining at the time of filing the application. The doctrine of equivalents as I have described it is an auxiliary means to extend the protection to methods that are fairly identical and which can therefore be described as modifications of the patent.

Otherwise the patent protection would prevent both further research and development and a legitimate competition on the market place. This is especially true when the method that is patented is not in itself an expression of anything new and patentable, as is the case with the analogy method patents. What is conclusive is therefore a concrete assessment of whether the method has sufficient closeness to the method in the patent claim so that it can be characterised as being fairly identical. Anything else would be deviating too far from the point of departure that the patent claim determines the extent of protection."

Norway's highest court has thus acknowledged for the first time that there is a doctrine of equivalents and that the applicable criteria are as follows:

  • The infringing object solves the same problem as the patented invention.
  • The modifications made were obvious to the skilled person.
  • The infringing object was not part of the free technique (known and freely available technical knowledge).

These three criteria had been proposed by leading IP scholar Professor Are Stenvik as a good approach, for which he found support in the case law and doctrine of other European countries - notably the other Nordic countries, Germany and England. The three criteria had been applied as a test of equivalence in a number of cases decided by the district and appeal courts, but never been ruled on by the Supreme Court.

The Supreme Court also made clear that where process patents are concerned, the second criterion does not mean that any method that the skilled person would consider obvious falls under the scope of the patent, but that to be caught, a method must be a modification of the method directly protected under the claims.

The ruling may make it more difficult for owners of analogy method patents – there are still a few of them, including supplementary protection certificates - to assert their patents against generic drug manufacturers.


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