SilverStar (Ginsei Igo) is the Japanese edition of North Korean program KCC Igo. Its is a commercial go playing program written for the Windows operating system.
KCC Igo was the Gifu Challenge winner from 2003 to 2006.
The earliest versions of KCC Igo and Hamlet which competed from 1997 through 2000 were accused of plagiarizing Prof. Chen Zhixing's program HandTalk. It is unknown whether subsequent versions continue to plagiarize, due to anti-tracing measures added to KCC Igo. This stigma extends to the present day; the largely rewritten KCC Igo was denied entry to the 2009 Computer Olympiad. The names of the programmers of "Ginsei Igo" are not known. A request to the Japanese distributor of the commercial version was made early in 2012, but no reply was given.
Korean site: http://www.i-silverstar.com/
Publisher of Silver Star Go DX
Article about the program: "The World Best: Eunbyul 2010"
(not sure if it is just an advertisment or really true)