While Enercon has made no formal statement on the matter, the legal action appears to be the culmination of a dispute on patent rights that negotiations have failed to resolve. Enercon began extensive patenting of its technology in 1994 after an industrial espionage scare which came two years after US Windpower, which later became Kenetech Windpower before being bought by Enron and then GE Wind, tried to get its variable speed technology patented at the European Patent Office. Enercon and several other companies opposed the application.
Last year, Enercon and GE reached a bilateral settlement on that dispute (Windpower Monthly, June 2004) by agreeing a "cross licence with worldwide and long term application." Enercon now has well over one hundred patents for its technology and, like all companies, is fiercely protective over them. This latest case against Vestas is being handled in Germany. Both companies refuse to comment further.