American Superconductor Corp., a Devens, Massachusetts-based supplier of wind-turbine electrical components, rose the most in 10 months after U.S. prosecutors charged its former largest customer with stealing the company’s technology.
AMSC gained 13 percent to $2.64 at the close in New York, the most since Aug. 2.
Prosecutors secured an indictment of the Chinese turbine maker Sinovel Wind Group Co., two of its executives and a former AMSC engineer in in federal court in Madison, Wisconsin, yesterday. The engineer, Dejan Karabasevic, pleaded guilty in Austria to stealing AMSC source code for turbine controllers on behalf of Sinovel.
AMSC, which lost more than $1 billion in market value after the theft became public, is seeking $1.2 billion in damages in Chinese courts. Sinovel accounted for 70 percent of AMSC’s sales in 2009 and is accused of using stolen AMSC source code for computer controllers inside turbines and violating sales contracts.