SEOUL, South Korea: South Korea's Supreme Court upheld a lower court decision acquitting Samsung Electronics Chairman Jay Y. Lee of charges related to a controversial 2015 merger, ending one of the most high-profile legal battles in the country's corporate history.

The ruling clears Lee of accounting fraud and stock manipulation charges tied to the US$8 billion merger between Samsung C&T and Cheil Industries. Prosecutors argued that the deal was engineered to consolidate Lee's control over the conglomerate following his father's incapacitation.

The Supreme Court's decision affirms two earlier rulings, including one from an appeals court that found no wrongdoing in the merger.

Lee's legal team welcomed the outcome, saying in a statement they were "sincerely grateful" to the court and that the ruling confirmed the merger was legal.

The case had cast a long shadow over Lee's leadership at Samsung for nearly a decade, beginning shortly after the 2014 heart attack that left his father, Samsung patriarch Lee Kun-hee, in a coma. The merger laid the foundation for Lee's succession at the helm of the tech empire.

While the verdict had been widely anticipated, it arrives at a pivotal time. Samsung is in a race to close the gap in AI chip development, facing fierce global competition in a fast-evolving semiconductor industry.

The Supreme Court's decision removes a lingering legal distraction, allowing Lee to focus entirely on steering Samsung through one of its most strategically significant periods.

Samsung Electronics shares were modestly higher after the ruling, rising 1.7 percent.