Rank in Judo are ranked in ascending numerical order. The ninth ("kudan") and tenth degree black belt ("jūdan") and, theoretically, those higher, have no formal requirements. Only 15 individuals have been promoted to the rank of Kōdōkan 10th dan. On January 6, 2006, three individuals were promoted to this rank simultaneously: Daigo Toshirō, Ichirō Abe, and Ōsawa Yoshimi. This is the most ever at the same time, and the first in 22 years. No one has ever been promoted to a rank higher than 10th "dan", but in theory the Judo rank system is not limited to 10 degrees of black belt. The
World Judo Championships except Oceania and Antarctica. The World Judo Championships team competition began in 1994. women's competition began in 1997, and after 1998 it was held once every four years until 2006. The competition will be held every year from 2007. Judoka who participate in the individual world championships often do not participate in the team competition. World Judo Championships The World Judo Championships are the highest level of international judo competition, along with the Olympic judo competition. The championships are held once every year (except the years when the Olympics take place) by the International Judo Federation, and qualified judoka compete