In California, an adopted child obtains all the same rights of inheritance as a biological child born to the adoptive parent. He or she can inherit either from or through a deceased adoptive parent. Generally speaking an adopted child at the same time loses such inheritance rights from or through his or her biological parents. Accordingly, the descendants of a deceased adopted person are heirs of the decedent’s adoptive parents but are not heirs of the decedent’s biological parents. (Note: Limited exceptions exist, including an exception for adoptions by a step parent who married a biological parent of an adopted child.)

In September, 2018, in Estate of Fusae Obata, the California Court of Appeal (1st Appellate District) decided whether California law recognizes a Japanese adult adoption practice called Yoshi-engumi when applying California inheritance law. Yoshi-engumi adult adoptions in Japan have very different motivations and purposes than adoptions in Western countries.

Unlike adoptions in Western countries – which usually involve minor children — Japanese adult adoptions are driven by Japanese concepts of extended family (or house), ancestor worship, and supporting one’s elderly parents. When there are no biological sons, adult adoptions in Japan are often motivated by the desire to continue a house that would otherwise die.

In Estate of Fusae Obata, the opposing parties argued over whether the descendants of a deceased Japanese man — who while alive had been adopted as an adult in Japan through Yoshi-engumi — lost their right to inherit from the deceased man’s biological parents.

California looks to the law of the jurisdiction where a person is adopted to determine whether the foreign adoption is valid and looks to the law in the jurisdiction where a person dies to determine who is an heir. Thus, the laws of two different jurisdictions are necessary to determine if an adoption outside California created or severed inheritance rights in California.

In Estate of Fusae Obata, the Court rejected the argument that the adult adoption created under the Japanese Yoshi-engumi adoption laws was not valid. It was immaterial that the Japanese adoption did not, “satisfy the elemental characteristics of adoption recognized in California”.

The very different natures and legal requirements between a Japanese adult adoption and a California adoption were irrelevant. All that matters for determining inheritance rights in a California probate proceeding is that under Japanese law, “the adopted person is considered a biological child for all purposes.”

Accordingly, the Court decided that, “the 1911 adoption severed the relationship between decedent’s [Japanese] father and his natural parent.” Thus, the descendants of the Japanese man who was adopted could not inherit through him from his biological parents.

The foregoing, of course, is not limited to Japanese adult adoptions. California Probate proceedings where adoptions either in another state or in another country are relevant would likewise look to the law of the foreign jurisdiction where the adoption occurred on the adoption issue.