Despite the rulings, the Enercon patents remain valid in the two countries until the appeals have been decided, a procedure likely to take around a year. If Wobben loses, he loses the Enercon patent in question in the relevant country and incurs legal costs.
If the appeal should go against Vestas, its financial punishment may include damage claims for the offending turbines installed in either country before the date of the judgement, probably calculated on the basis of the lost licence fees, according to experts. Otherwise its options, should it lose, include applying to Enercon for a license to use the disputed technology or deciding not to employ the technology in the relevant country.
Whatever the outcome, "the circumstances relating to the patents will not have a material effect on the financial position of the group," says Vestas.
Under patent procedures, disputes over European patents are handled by national patent offices, not the European Patent Office (EPO). Last month in the Netherlands, the district court of The Hague ruled that Wobben's patent on frequency control (EP1282774) is invalid, "acquitting Vestas from infringement charges," states the Danish company. The court made the same judgements in January on Wobben's patents on voltage control. Wobben appealed similar judgements by the British High Court in November (Windpower Monthly, December 2007) and is expected to appeal the Dutch decisions too.
The national patent cases are unusual in that national authorities will usually stall proceedings until the European patent procedure is complete. All three of the patents involved, however, remain in the opposition phase at European level. The EPO's Rainer Osterwalder could not account for why the British and Dutch authorities had ignored usual custom and dealt with the cases.
Acting for Enercon, Klaus Göken, German and European Patent Attorney of Eisenführ, Speiser and Partner, says: "Such decisions in the UK, the Netherlands or other countries have no bearing on decisions at the European Patent Office."
On remaining patents in dispute with Enercon in Canada and Ireland regarding grid connection, there is nothing to report, says Vestas. It does not expect judgements on these cases until the end of 2008.