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Wind Turbines Patent Obvious and Invalid Court of Appeal Rules

Patents provide protection and encouragement to inventiveness and novelty, not to obvious developments of others’ ideas. The Court of Appeal made that point in finding invalid a patent in respect of wind turbine arrays.

A company had patented a method of operating pitch-controlled wind turbines so as to gradually reduce rotor speeds in high winds in a manner that minimised instability and power surges. It launched proceedings against a turbine manufacturer and others, alleging that they had infringed the patent in the installation of three offshore wind farms.

A judge rejected the company’s claim on the basis that the method was obvious in the light of a learned article that had been published by an expert in the field 13 years before the patent’s priority date. Although the method was not the only means of reducing power output and turbine fatigue in stormy conditions, it disclosed an approach that would have been obvious to a wind turbine engineer.

In dismissing the company’s challenge to that ruling, the Court rejected arguments that the judge’s approach to the issue of obviousness had been driven by hindsight. On reading the article, a skilled engineer would have seen the goal of improving power grid stability in high winds as well worth pursuing. The judge’s decision disclosed no error of principle or reasoning.