Accompanied by a certificate of registration as a Tokubetsu Hozon Token [Sword especially worthy of preservation] no. 107073 issued by the Nihon Bijutsu Token Hozon Kyokai [Society for the Preservation of the Japan Art Sword] on 29th September 1986
Born in 1607 Masahiro was the son of Yoshinobu, first named Sadenjiro and then Yashichibei. He worked originally as a sword smith under the name Masanaga. He signed with the name Masahiro from 1625, and was given the title Kawachi daijo in 1628. He died in 1665 at the age of 59. Several generations with the name Masahiro followed, the second and third also being entitled Kawachi daijo.
The inscription contains the result of a cutting test 'O-Kesa Otoshi', in which a body is cut from across one shoulder and through the opposite part of the trunk. The owner of the sword Kakumu Genzaemon (no) jo Tadayasu is said to have been a fencing master in the service of the lord of Karatsu castle, and this sword was long in the possession of the Kakumu family.