Facts
Company Y. AG, the leading generic manufacturer in Switzerland, filed a nullity action against Swiss Patent No. 691 537 owned by company X. A/S, specialized in central nervous system medications. The patent claimed a crystalline base of citalopram with a purity of over 99.8% or 99.9%. The Commercial Court of the Canton of Zurich granted the main claim and declared the patent null, finding that it did not disclose a new invention and did not achieve a previously unknown technical effect. X. A/S appealed this decision.Considerations
The case law of the Boards of Appeal of the European Patent Office can influence the application of Swiss patent law, as the patentability requirements are harmonized at the European level.
For a patent to be granted for the manufacture of a substance already known, but particularly pure, the claimed degree of purity must be inaccessible with known processes. The burden of proof…