Rybka is a computer chess engine designed by International Master Vasik Rajlich

Vasik Rajlich

Vasik Rajlich is an International Master in chess and the author of Rybka, one of the strongest chess playing programs in the world. Rajlich is a dual Czechoslovakian-American citizen by birth; he was born in the United States of America to Czech parents, at that time graduate students, but grew...

. , Rybka is one of the top-rated engines on chess engine rating lists and has won many computer chess tournaments. Although Rybka won four consecutive World Computer Chess Championship

World Computer Chess Championship

World Computer Chess Championship is an annual event where computer chess engines compete against each other. The event is organized by the International Computer Games Association...

s from 2007 to 2010, it was stripped of these titles after an International Computer Games Association

International Computer Games Association

The International Computer Games Association was founded as the International Computer Chess Association in 1977 by computer chess programmers to organise championship events for computer programs and to facilitate the sharing of technical knowledge via the ICCA Journal.Renamed the 'ICGA' in...

 panel concluded in June 2011 that Rybka plagiarized code from both the Crafty

Crafty

Crafty is a chess program written by UAB professor Dr. Robert Hyatt. It is directly derived from Cray Blitz, winner of the 1983 and 1986 World Computer Chess Championships....

 and the Fruit chess engines.