Semiconductor Ultra-Pure Water Technology Leak Case

On May 15, 2026, the Supreme Court of South Korea delivered a landmark ruling in a case involving a Chinese national who leaked proprietary ultra-pure water technology used in semiconductor manufacturing. The defendant, employed by a Korean company specializing in ultra-pure water systems essential for chip production, secretly copied critical technical data and design documents with the intention of transferring them to a prospective employer. The leak targeted advanced purification processes that remove microscopic contaminants, a technology vital to semiconductor yield rates. The Supreme Court affirmed lower court decisions classifying the stolen technology as protected industrial technology under South Korea's stringent industrial security laws, rejecting the defense's argument that the information constituted general technical knowledge. This ruling underscored the strategic importance of ultra-pure water systems within the global semiconductor supply chain.

The Supreme Court of South Korea upheld the conviction, definitively classifying the leaked ultra-pure water technology as protected industrial technology. The defendant received a multi-year prison sentence and substantial fines, reinforcing stringent penalties for technology theft targeting strategic domestic industries.

The central dispute was whether the leaked ultra-pure water technology qualified as legally protected industrial technology under South Korea's Act on Prevention of Divulgence and Protection of Industrial Technology, or whether it constituted general, unprotected technical knowledge. The defense argued the technology was widely known, while prosecutors contended it was a core national asset integral to semiconductor manufacturing competitiveness.

The ruling sent a strong deterrent message against industrial espionage targeting South Korea's semiconductor ecosystem, particularly regarding enabling technologies like ultra-pure water. It heightened awareness among foreign-invested companies and multinational employees about the severe legal consequences of technology misappropriation, while also prompting Korean firms to strengthen internal security protocols for foreign nationals handling sensitive technical data.