Supplementary Provisions, Article 21
第二十一条
A person who was an insured person of the health insurance administered by the government prescribed in Article 5, paragraph (2) of the Health Insurance Act Before the October 2008 Amendment (hereinafter referred to as "former government-managed health insurance") on the day before the date of enforcement of the provisions of Article 4 (excluding a person who, on that day, falls under any of the grounds listed in the items of Article 36 or Article 38, items (i) through (iii) of the Health Insurance Act Before the October 2008 Amendment) is to become, on the date of enforcement of the provisions of Article 4, an insured person of the health insurance administered by the Japan Health Insurance Association prescribed in Article 5, paragraph (2) of the Health Insurance Act as Amended in October 2008.
第四条の規定の施行の日の前日において平成二十年十月改正前健保法第五条第二項に規定する政府が管掌する健康保険（以下「旧政管健保」という。）の被保険者であった者（同日において、その者が平成二十年十月改正前健保法第三十六条各号又は第三十八条第一号から第三号までに掲げる事由に該当する場合を除く。）は、第四条の規定の施行の日において、平成二十年十月改正健保法第五条第二項に規定する全国健康保険協会が管掌する健康保険の被保険者になるものとする。