Dan (rank) is by far the most recognizable symbol to the general public. The highest dan ranks are sometimes reserved for the founder or leaders of a style and only high-ranking students can be promoted to them. For example, only five living people hold a tenth dan in judo and only about thirty-five worldwide have been promoted to the rank since its inception; of those 10th dan promotions only fifteen were conferred by the Kodokan, all of them to Japanese judoka. This has led to upper level ranks becoming extinct in some arts. In other styles, the dan ranks are not the
Kosen judo ordinary contenders, a captain and a vice-captain, and five replacements in case of injuries or retirements. Every match is composed of a single, six-minute round, changed to an eight minute round when the contenders are captains or vice-captains. The league is hosted as a "kachi-nuki shiai", meaning every winner stays on the mat to face the next member of the rival team. At the end of the event, victory is given to the team with the highest numbers of matches won or with the last man on the field. Kosen judo Today, the term "kosen judo" is frequently used to