In Zen-Buddhism, Dharma transmission is a custom in which a person is established as a "successor in an unbroken lineage of teachers and disciples, a spiritual 'bloodline' (kechimyaku) theoretically traced back to the Buddha himself." The dharma lineage reflects the importance of family-structures in ancient China, and forms a symbolic and ritual recreation of this system for the monastical "family".
In Rinzai-Zen, inka shōmei is ideally "the formal recognition of Zen's deepest realisation", but practically it is being used for the transmission of the "true lineage" of the masters (shike) of the training halls. There are only about fifty to eighty of such inka shōmei-bearers in Japan.
In Soto-Zen, dharma transmission (shiho) provides access to only a relatively low grade. It is listed as a requirement for the very lowest ecclesiastical status, that of an instructor third class (santō kyōshi) further training is required to become an oshō.