Due to the international nature of many patent conflicts, the importance of foreign invalidity judgments is a common theme in patent proceedings. One question is whether courts should consider foreign invalidity judgments regarding the same European patent and, if so, what importance should be attached to foreign judgments.

According to a recent preliminary decision from the Danish first-instance IP court (the Maritime and Commercial High Court), the answer seems to be that little importance is attached to foreign invalidity judgments.(1)


AstraZeneca filed a request for a preliminary injunction against Hexal's sale of a generic version of AstraZeneca's pharmaceutical Seroquel Prolong on the Danish market. The request was based on a European patent which had been invalidated in proceedings between the parties (or their affiliates) in Germany, England, Italy, Belgium, Holland and Spain. The German, English, Spanish and Dutch decisions were final appeal court judgments, while the Belgian and Italian decisions were first-instance judgments which had been appealed. The equivalent American patent had been upheld in the United States in the second-instance court.

In Danish preliminary injunction proceedings, the rights holder is not required to prove infringement. It is sufficient for infringement to be proved on a balance of probabilities. When deciding on the infringement probability issue, the court must include an assessment of the validity of the patent if an invalidity objection has been raised. However, in preliminary injunction proceedings, the court cannot invalidate the patent.

Hexal claimed, among other things, that infringement had not been proved on a balance of probabilities because the patent in dispute was likely to be invalid or, at least, there were serious doubts regarding the validity of the patent. In order to substantiate the invalidity objection, the six foreign judgments were cited and most of the prior art from the other European cases was produced.


The court concluded that Hexal had not proved that the patent was invalid and therefore did not attach any real importance to the six European invalidity judgments.

The decision confirms the general impression that it is difficult to argue patent invalidity successfully in Danish preliminary injunction proceedings.

Although the court did not attach importance to the six foreign judgments in their own right, it did not consider the validity to have been proved by clear and convincing evidence, but only on a balance of probabilities. Therefore, the court made the preliminary injunction conditional on AstraZeneca providing security.

The Danish patent is subject to final invalidity proceedings before the same court and the preliminary injunction case has been appealed.

For further information on this topic please contact Jeppe Brinck-Jensen or Bjørn von Ryberg at Accura Advokatpartnerselskab by telephone (+45 3945 2800) or email ( or The Accura Advokatpartnerselskab website can be accessed at


(1) The decision (in Danish) can be found here.

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