Japan.

Japan operates a civil-law inheritance system rooted in the German BGB tradition. The 民法 (Civil Code, 1896 with major 2018 amendments) governs the substance of succession; the 相続税法 (Inheritance Tax Act) imposes tax at progressive rates up to 55% — the highest in the developed world; and the 法の適用に関する通則法 (2007) controls choice-of-law for cross-border estates. Japanese family courts (家庭裁判所) supervise contested partition.

Three features make Japanese succession law structurally distinctive. 遺留分 (iryūbun) — the forced heirship rules — protects descendants, ascendants, and the surviving spouse against disinheritance, with the 2018 amendments converting it from a real-rights claim into a monetary-value claim. The 55% top tax rate combined with rigorous valuation rules can deplete an estate substantially, and the 10-month filing deadline for 相続税 creates significant administrative pressure. And while Japan has an estate-tax treaty with the United States dating from 1954, it has none with Canada — leaving Japanese-Canadian binational families exposed to genuine double taxation.

The memoranda in this series address the recurring fact patterns in Japanese cross-border estate planning — including the iryūbun tension with foreign testamentary freedom, the worldwide-asset taxation regime for Japanese tax residents, US-Japan treaty mechanics under the 1954 estate-tax treaty, the absence of treaty coordination with Canada, and the interaction between Japanese succession and Canadian deemed disposition or US federal estate tax.