Toshihide Isamu Iguchi (井口俊英) (1951–2019) was an Executive VP and U.S. Government Bond trader at Daiwa Bank's New York Branch, who was responsible for $1.1 billion in unauthorized trading losses accumulated over a period of 12 years beginning in 1983.
Source: “Toshihide Iguchi”, English Wikipedia (CC BY-SA 4.0), excerpt