Philip Gabriel Pettersson, also known as 'Stakkato', was 16 years old at the time of the crime, committed in 2004. The computer systems for Cisco were hacked, and source code for its Internetwork Operating System (IOS) subsequently appeared on Russian bulletin boards.
As part of the same case, which featured five hacking indictments, Pettersson was also accused of hacking NASA's Ames Research Center and Advanced Supercomputing Division.
The US indicted Pettersson in May, but the Swedish Ministry of Justice, which does not extradite its own citizens, agreed to take over the prosecution.
"The intrusions to Cisco Company and NASA are regarded as computer intrusions according to the Swedish law," said senior public prosecutor Chatrine Rudstrom of the International Public Prosecution Office in Stockholm. "After the police investigation is terminated, as the prosecutor in the case, I will decide whether the suspect, Mr Philip Pettersson, will be prosecuted or not."
Pettersson had already been prosecuted for several computer intrusions, said Rudstrom. It may be the case that the sentences handed down for these previous convictions will be enough to cover convictions for these crimes as well.