Mochibun kaisha (持分会社) are a class of corporations under Japanese law.^[1] While mochibun kaisha have legal personality as corporations, their internal functions are similar to partnerships, as they are both owned and operated by a single group of members (社員, shain).

This section does not cite any sources. (December 2010)

There are three types of mochibun kaisha:

• Gōmei gaisha, in which all members have unlimited liability for the company's debts (similar to a general partnership)
• Gōshi gaisha, in which some members have unlimited liability and some have limited liability (similar to a limited partnership)
• Gōdō gaisha, in which all members have limited liability (very similar to a U.S. limited liability company)

Mochibun kaisha are formed by preparing articles of incorporation and depositing the articles with a local Legal Affairs Bureau.

The Japanese civil code also provides for partnerships (組合, kumiai), a different type of business organization. Civil code partnerships lack legal personality and are mainly used for investment funds and professional firms.