According to CNN, the Swiss courts rejected the extradition request on grounds that the US authorities failed to provide all the legal records Switzerland had required and that Polanski had a reasonable right to think he would not be arrested if he visited the country.
U.S. prosecutors could not apply again to Switzerland but they could try to apply other countries to detain and extradite him if he leaves Switzerland.
The director as arrested last year and has been fighting extradition. He was charged of raping a 13-year old girl back in 1977. He pleaded guilty to the charge but left the country before he was sentenced.