Tachi signed Masatsune (Hachisuka Masatsune)

Masatsune was a leading swordsmith of the Ko-Bizen school, active in Bizen Province from the late Heian through the Kamakura period. Ranked alongside Tomonari as a master of the school, he left behind more surviving signed works than any other Ko-Bizen smith.

This tachi measures 77.6 cm in blade length, with a curvature of 2.6 cm, a base width of 2.9 cm, a tip width of 1.6 cm, and a kissaki length of 2.5 cm. The steel is a fine, well-forged ko-itame grain with ji-nie and ji-utsuri, while the hamon shows small midare with abundant ashi and yo, deep ko-nie, and a boshi that curves gently into a small return. Its elegant, high-koshizori form and the quality of its signature and craftsmanship make it regarded as the most archaic and finest among Masatsune's signed works.

From the Toyotomi era onward, the sword was held by the Hachisuka clan, daimyo of Awa domain (present-day Tokushima Prefecture), and remained in the family until the Meiji Restoration — the source of its name, "Hachisuka Masatsune." It later passed through several owners before coming into the possession of Yasuhiro Komatsu, founder of the Fukuyama-based food packaging manufacturer FP Corporation.

The blade was designated a National Treasure on March 29, 1952. Following Komatsu's death, his collection was donated to the Fukuyama Museum of Art in Fukuyama City, Hiroshima Prefecture, which continues to hold the sword today.