Half-sibling who cared for mother 27 years wins Supreme Court ruling over inheritance claim

The Supreme Court has sided with a woman who cared for her mother for 27 years, ruling that other children cannot claim a legally guaranteed inheritance share against the 198 million won ($133,000) she received during the mother's lifetime.

According to legal sources Thursday, the Supreme Court's Third Division, presided over by Justice Oh Seok-jun, overturned a lower court ruling that had favored the plaintiff — a half-sister identified only by her surname Park — and remanded the case to the Daegu District Court. Park had sued her half-sibling, surnamed Shin, demanding her portion of the legally protected inheritance share from assets their mother had transferred to Shin before her death.

Shin had supported their mother for 27 years, covering expenses including nursing home fees and mobile phone bills. In November 2016, the mother transferred her entire estate of approximately 198 million won to Shin, the daughter who had cared for her. The mother died in 2022. At the time of her death, the only remaining asset was a bank deposit of 310,000 won, which was divided among three children, including Park and Shin.

Park filed a lawsuit in 2023, seeking her share of the legally guaranteed minimum inheritance — known as "yuilbun" — from the 198 million won the mother had given Shin in 2016. The yuilbun system ensures that all family members are entitled to a minimum portion of a deceased person's estate regardless of the deceased's wishes.

Both the first and second courts declined to recognize Shin's contribution as a caregiver. The second court in particular held that even though the Constitutional Court had ruled the civil code provisions on the yuilbun system incompatible with the Constitution, the existing law remained in effect until amended — and on that basis ordered Shin to pay Park approximately 25 million won.

The Supreme Court reached a different conclusion. It held that if related litigation was already under way at the time of the Constitutional Court's incompatibility ruling, the amended civil code provisions could be applied retroactively — even to inheritance cases that began before April 25, 2024.

The Constitutional Court had ruled in April 2024 that civil code provisions failing to account for a caregiver's contribution when calculating the yuilbun share were incompatible with the Constitution, finding that the provisions "create an unjust situation in which an heir who has supported the deceased for a long period must return to non-contributing heirs the assets received as compensation for that care."

The Supreme Court said "the ruling of constitutional incompatibility must be considered retroactively applicable to cases still pending before the courts in which the previous legal provisions formed the basis of the trial."