Yasuji was thus the first to use the name "Komagawa Kaishin-ryū" outside of Toyama since the incident when he relocated to Tokyo at the start of the Taishō period. In most koryū, teaching duty is either fully delegated (as in present Katori Shintō-ryū) and/or divided between many teachers who have received official permission to teach, some of whom are sometimes permitted to teach only a certain part of the curriculum. This permission is usually granted through a document, most often called a menkyo kaiden or "license of transmission", which certifies that the holder knows all the technical curriculum that can be taught or that he is qualified to teach (sometimes there are "secret teachings" or "okugi" that are only transmitted from sōke to sōke). Komagawa Kaishin-ryū however is unusual in that the only authorized teacher is the sōke himself. This means that in order to learn a technique or kata, you have to learn it from Kuroda Tetsuzan directly. This is in order to preserve the kata's original forms as best as possible. The same holds true for all "ryū" of which Kuroda sensei is the sōke. There is only one actual dōjō, the Shinbukan Kuroda Dojo (振武舘 黒田道場) in Saitama, although there are a total of six "keikokai" or practice groups around the world. Two of these are in Japan (Kami-itabashi in Tokyo and Amagasaki in Kansai), three in the United-States of America (San Antonio, Encinitas and Chicago) and one in France (Paris). The locations outside Japan are visited at least once a year. Kuroda sensei personally examines the candidacy of prospective students; enquiries should be made to the geographically closest practice group, excluding those in Japan.