South Korean patent fights: court denies LG Chem injunction against JS Energy, mediation takes center stage in Hanmi and Hanwha Semitech case

Context:

• In August 2024, LG Chem sued JS Energy, the Korean subsidiary of Chinese cathode maker Ningbo Ronbay New Energy Technology, at the Seoul Central District Court. The suit covers five patents on high-nickel nickel-cobalt-manganese (NCM) cathode materials, which largely determine battery capacity and make up about 40% of battery costs. JS Energy challenged all five patents at the Intellectual Property Trial and Appeal Board (IPTAB), which had ruled on all of them by July 2026, upholding four and invalidating one. LG Chem asked for a preliminary injunction (PI) in January 2026.
• Hanmi Semiconductor, which has long been SK Hynix’s main supplier of thermocompression (TC) bonders, sued Hanwha Semitech in a court in South Korea in December 2024. TC bonders stack and bond dynamic random-access memory (DRAM) dies for high-bandwidth memory (HBM) used in AI accelerators. Hanwha Semitech entered the market in March 2025, challenged Hanmi’s patents in an invalidation trial, and filed a countersuit over three of its own patents.