Article 3-12-12Calculation of the Insured Period Relating to the Specific Period
第三条の十二の十二（特定期間に係る被保険者期間の計算）
With regard to the insured period relating to the specific period, as specified by Order of the Ministry of Health, Labour and Welfare, the month that includes the first day of the specific period is included in it, and the month that includes the last day of the specific period is not included in it; provided, however, that where the first day and the last day of the specific period fall in the same month, that month is not included in the insured period relating to the specific period.
特定期間に係る被保険者期間については、厚生労働省令で定めるところにより、特定期間の初日の属する月はこれに算入し、特定期間の末日の属する月はこれに算入しない。ただし、特定期間の初日と末日が同一の月に属するときは、その月は、特定期間に係る被保険者期間に算入しない。
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specific periodmachine translation
「特定期間」
The time during which a specific insured person (特定被保険者) was insured and their dependent spouse (被扶養配偶者) was, as that insured person's spouse, a category III insured person (第三号被保険者) under the National Pension Act, as Article 78-14, paragraph (1) of the Employees' Pension Insurance Act defines it; after a divorce or similar event, the dependent spouse may ask for the standardized remuneration (標準報酬) for that time to be revised and decided.
Defined inArticle 3-12-10, paragraph (1)