LS Cable & System's submarine cables at the company’s East Sea facility. (LS Cable & System) Police have concluded that Taihan Cable & Solution improperly obtained trade secrets tied to submarine cable plant technology from rival LS Cable & System, escalating a major legal battle between South Korea’s top two cable makers.The Gyeonggi Nambu Provincial Police Agency said Thursday it referred 13 individuals and three corporations to prosecutors on charges of violating the Unfair Competition Prevention and Trade Secret Protection Act.Those referred include four Taihan Cable executives and employees, seven officials from the architecture firm Gawoon Comprehensive Architects, and two officials from an equipment company.Police allege Taihan Cable obtained LS Cable’s confidential factory design information while building a submarine cable plant in Dangjin, South Chungcheong Province, between 2022 and 2023.Investigators believe Gawoon leaked internal LS Cable materials to Taihan Cable despite confidentiality agreements signed with LS Cable.The case centers on whether submarine cable plant designs themselves qualify as trade secrets.Submarine cable plants require highly specialized layouts and equipment to manufacture, transport and store the ultra-heavy cables, which are produced in continuous sections stretching tens to hundreds of kilometers.LS Cable has argued that such factory designs embody years of accumulated engineering know-how and should be treated as core trade-secret assets.The company developed ultra-high-voltage submarine cables in 2007, becoming the world’s fourth company to do so, and built Korea’s first dedicated submarine cable plant in 2009.Gawoon had exclusively handled the design of LS Cable’s submarine cable plants from 2008 to 2023 before later signing a contract with Taihan Cable, the industry’s No. 2 player.Taihan Cable has long faced suspicions that it selected Gawoon partly to gain access to LS Cable’s accumulated submarine cable expertise.Police launched the investigation in 2023 and wrapped up the case nearly three years later.