Okan (王冠戦), literally meaning 'crown', is a small-scale tournament that only opens to players from the Nagoya branch of the Nihon Kiin. Its history can be dated back to 1950.
In its latest form, the main tournament is a knockout event by 12 players, most qualified from preliminary tournaments. The winner goes on to challenge the title holder in a single game.
- Most titles went to a few elite players.
- Famous players from Nagoya branch include Shimamura Toshihiro and Iwata Tatsuaki, both winning the title many times.
- Yamashiro Hiroshi notably won the title 15 times.
- The Hane family (father Yasumasa and son Naoki) has among them 16 titles.