第百六十五条（親族が事業に専ら従事するかどうかの判定）
Article 165Determination of Whether a Relative Is Exclusively Engaged in a Business
The determination of whether a spouse or other relative who shares livelihood with a Resident prescribed in Article 57, paragraph (1) or (3) (Special Provisions on Necessary Expenses If Relatives Work Exclusively for a Resident) of the Act is exclusively engaged in the business that the Resident carries on as prescribed in those provisions is made according to whether the period of exclusive engagement in that business exceeds six months in the year; provided, however, that in the case of paragraph (1) of that Article, where the case falls under any of the following items, it suffices that the relative is exclusively engaged in that business for a period exceeding one-half of the period during which the relative is found to be able to engage in that business.
that business was not carried on throughout the year because of the commencement, closure or suspension of the business or the death of the Resident in the middle of the year, the seasonal nature of the business, or other reasons;
当該事業が年の中途における開業、廃業、休業又はその居住者の死亡、当該事業が季節営業であることその他の理由によりその年中を通じて営まれなかつたこと。
the person engaged in that business was unable to engage in it throughout the year as a relative sharing livelihood with the Resident because of death, long-term illness, marriage or other reasonable grounds.
当該事業に従事する者の死亡、長期にわたる病気、婚姻その他相当の理由によりその年中を通じてその居住者と生計を一にする親族として当該事業に従事することができなかつたこと。
In the case referred to in the preceding paragraph, where there is a period during which a relative prescribed in that paragraph is a person falling under any one of the following items, that period is not included in the period of exclusive engagement in the business prescribed in that paragraph.
a person who is a student or pupil of a school under Article 1 (Scope of Schools), Article 124 (Specialized Training Colleges) or Article 134, paragraph (1) (Miscellaneous Schools) of the School Education Act (excluding a person who attends classes at night and engages in that business mainly in the daytime, a person who attends classes in the daytime and engages in that business mainly at night, a student or pupil of a school under Article 124 or Article 134, paragraph (1) of that Act who does not attend regularly, and any other person found not to be prevented from engaging exclusively in that business);
a person who has another occupation (excluding a person whose time engaged in that occupation is short and any other person found not to be prevented from engaging exclusively in that business);
他に職業を有する者（その職業に従事する時間が短い者その他当該事業に専ら従事することが妨げられないと認められる者を除く。）
a person whose ability to engage in a business is significantly impaired by senility or other mental or physical disability.
老衰その他心身の障害により事業に従事する能力が著しく阻害されている者