Oteai

The Oteai ("grand meeting") was the foundational ranking tournament of Japanese professional Go, used by the Nihon Ki-in from 1924 to determine the dan ranks of professional members. It ran in Spring and Autumn sessions, with professionals gathering to play around eight games per session. Players earned promotions based on winning percentages, with requirements becoming increasingly stringent at higher ranks. The Oteai was discontinued in 2003 (Kansai Ki-in in 2004), replaced by a modernized system. For nearly 80 years, this tournament served as the backbone of the Japanese professional ranking system, and its game records provide a rich archive of 20th-century Go.