Lee, who is also known as Jay Y. Lee, was found guilty of bribery and other corruption charges in 2017. But he walked free the following February when an appeals court threw out some of the charges and suspended his sentence.
The Supreme Court’s decision sends the case back to appellate court for retrial.
Lee is the vice chairman of Samsung and the son of ailing chairman Lee Kun-hee. The corruption scandal was dubbed the “trial of the century” and gripped South Korea for months. It was part of a huge influence-peddling scandal that has brought down the country’s former president Park Geun-hye.
Park, who is serving a 25-year prison sentence, was granted a retrial on some charges. She’ll remain in prison because not all of her convictions were overturned.
Lee’s part of the case is particularly significant because he is de facto head of Samsung, the world’s largest smartphone and memory chip manufacturer. His father was left incapacitated by a heart attack in 2014.
Samsung’s (SSNLF) stock was already trading in the red for much of the day, but its losses accelerated after the court’s decision was announced. The stock closed down 1.7% in South Korea.
The company is already grappling with other issues, including declining profits and a trade fight between South Korea and Japan that threatens the global supply chain for smartphones and electronic devices.