See the following for the historical usage of the term "banto."
The term existed as legal terminology in Article 43 of Japan's Commercial Code prior to its amendment in 2005 (reorganized as Article 25 after amendment). The terms "banto" and "tedai" were used in the code as examples of persons, who were employed for business activity and commissioned under certain or specific provisions, but they were removed with the 2005 amendment.
Banto/bangashira (samurai family)
The "bangashira" or "banto" at a samurai family enjoyed the highest status and reputation in the military sector and was called the "oban gashira" chiefly during the Edo shogunate, serving as the head of security for Ote-mon Gate (Main Gate) of the Edo Castle, as well as a captain in charge of the bakufu troop and of the cavalry in times of war or military campaign. The post was filled by a few bakufu hatamoto (direct retainers of the bakufu, which is a form of Japanese feudal government headed by a shogun) holding domains with more than 5,000 koku (of rice) yield each or fudai daimyo (hereditary vassal to the Tokugawa family) in the 10,000-goku class. Under the oban gashira was the "oban kumigashira" who served as a middle manager.
Although the higher status enjoyed by the oban gashira, who was merely a head of security and an army captain compared to "Ometsuke" or "machi-bugyo" (town magistrate) who were, in fact, hatamoto in the 3,000 koku class, appears strange from the modern perspective, persons appointed to take charge of defense and military affairs were regarded more important in the shogunate, which was by nature a military regime. Other posts included "koshogumi" in charge of security of the shogun and "shoinban" who was responsible for security in the shogun's sleeping chamber and other parts of the castle (who also was the second army captain of a shogunate troop at times of war).
The bangashira was the highest ranking post in security during peaceful times and a commander at war, likewise in various feudal domains. The bangashira also served as intermediary for retainers in the security division ("bankata") to report their views to the feudal lord. In some domains, the vassal with this authority was called "samurai-gashira" or "kumigashira" rather than bangashira. In a domain with both kumigashira and bangashira posts, the latter was higher in rank, although this is not necessarily true for all domains. There were instances in which the kumigashira ranked higher, such as when the kumigashira was a samurai daisho (troop commander) who was appointed to lead a cavalry.
Sadayoshi OKUNO (aged 54 at the time of the Genroku Ako Incident), who was a kumigashira for the Asano clan of Ako Domain, was granted 1000 koku rice yield, much higher than many chief retainers though being a son of a chief retainer and second only to Jodai (castle keeper) and hitto karo (head of chief retainers): Yoshio OISHI with 1500 koku. There are records describing Sadayoshi OKUNO also as bangashira, which may be evidence that the terms bangashira and kumigashira were synonymous in the domain.
The key to determine the power of the bangashira within the domain, along with his hereditary stipend and salary paid in accordance with his post, is whether he held the right to serve as intermediary between the lord and the military retainers and voice in personnel matters. The status of the bangashira in a domain varied in details by domains, ranking in importance after the chief retainers, toshiyori and churo (middle-level retainers) in some cases, and lower than yojin (lord chamberlain) in other cases. Notwithstanding, there is a clear trend in the order of rank of the bangashira in a feudal domain. In a small domain or a domain with a simple administrative system, the vassal ranking below the chief retainer was the yojin. In the small domain, the yojin supported the chief retainer in all matters and ranked higher than the bangashira. In a large domain, however, there were various ranks of retainers between the chief retainer and the yojin, such as toshiyori and churo, who supported the chief retainer, thus reducing the importance of the yojin's role to only general administrative matters and special issues, and at times reducing its rank lower than the bangashira. In the small domain, the bangashira, rusui (caretaker) and koyonin may have been roughly similar in rank, or the bangashira may have ranked higher. It was rare that the bangashira ranked higher than the Edo rusui or the koyonin. In the large domain, the bangashira ranked higher than the rusui and the koyonin. In both small and large domains, the bangashira ranked higher than monogashira (military commanders) and kyunin (upper class retainers).
The koshogumi bangashira (head of page office) and shoin bangashira (head of military patrol) who held important posts in the bakufu government were actually lower in rank than bangashira in feudal domains, and were often called kosho kumigashira or shoin kumigashira, and had their functions covered by the bangashira in the small domains. Very roughly speaking, the bangashira was appointed from persons in the 'upper-middle class' of vassals in each domain. In times of peace, appointments were based on family lineage.
Banto (mercantile house)
The banto in a mercantile family held the highest position among employees, especially during the Edo Period.
Employees started work at around age 10, working as apprentice ("decchi" in Osaka area and "kozo" in Edo area) and running errands and minor duties and eventually working their way up to "tedai" (clerk) or the banto (head clerk). The duties of the banto covered not only business management but also administrative affairs of the family and were allowed to wear haori (Japanese half-coat),which was not allowed for the tedai and others. At many mercantile families, employees up to tedai rank were expected to live with the merchant and his family, so the employee in banto position was finally freed from this obligation and was allowed to commute from his own home. Also, marriage was not allowed until reaching banto status in many cases. The banto may have been granted license from the employer to become independent and started his own business, but this was only possible after undergoing a struggle for survival and achievement of the banto status.