Kanemasa (包真) was a swordsmith of the school, a group of smiths residing near the - of Todaiji in Nara. The school takes Kanenaga of the late period as its de facto founder and prospered throughout the period. According to the , Kanemasa was "a disciple in the line of Kanenaga, and the first generation is transmitted as Yasuyasu," with successive generations continuing into the late period. Works by Kanemasa, together with those of Kanetoshi, are numerous from the period. The earliest signed works are dated to no later than the Oei era, with a documented example bearing the date Oei 2 (1405).
works characteristically show little individual eccentricity, instead presenting the traditional style of the school. The displays mixed with flowing and , well packed with a slightly whitish tone to the ground steel. The is generally a with a tightened , to which adheres brightly, often showing slight and . In the later Sue period, the temper broadens with more vigorous , , and appearing. The turns back in with a long , and file marks are typically . The observes that the in Kanemasa's work "richly manifests the seen in Kanenaga's work" and possesses "an archaic flavor" that "overflows with strength."
Among signed Kanemasa works, the earliest example is described as "a valuable reference piece for research on the school." The identifies an "unmistakably neat and careful workmanship" as the hallmark of production from the Oei era, with the praised as being "of good quality" and the "splendid." Kanemasa's oeuvre traces the arc of the tradition from its measured -derived restraint through to the more animated expression of the Sue period.