The truth dispute over allegations of "submarine cable technology theft" between LS Cable & System and Taihan Cable & Solution — South Korea's top two wire and cable makers — has been handed over to prosecutors. After more than three years of investigation, police concluded that Taihan unlawfully obtained LS Cable's trade secrets, raising the prospect that the conflict between the two companies will escalate into a full-blown courtroom battle involving substantial damages claims.
Origin of the case: Gawoon Architects… built know-how at LS, then contracted with Taihan
According to industry and investigative authorities on the 29th, the Security Investigation Division of the Gyeonggi Nambu Provincial Police Agency referred a total of 13 individuals — including four Taihan executives, seven officials from Gawoon Architects & Engineers, and two from an equipment supplier — along with three corporate entities to the Suwon District Prosecutors' Office on charges of violating the Unfair Competition Prevention and Trade Secret Protection Act. They are accused of stealing and illegally incorporating LS Cable's trade secrets, including design drawings, in the process of building Taihan's No. 1 submarine cable plant in Dangjin, South Chungcheong Province, between 2022 and 2023.
The case originated with Gawoon Architects & Engineers, which handled the plant design. From 2008 to 2023, Gawoon was the exclusive designer of LS Cable's submarine cable plants Nos. 1 through 4, accumulating know-how in the process. It then signed a contract with rival Taihan and began designing the Dangjin facility. Submarine cables must be manufactured in "long-length" form spanning tens to hundreds of kilometers without intermediate joints, with weights reaching thousands of tons. For this reason, LS Cable argues that the very layout of the specialized equipment used to produce, store, and transport such ultra-heavy cables embodies decades of know-how and constitutes a core trade secret. Police likewise concluded that Gawoon violated its non-disclosure agreement with LS Cable and provided internal materials to Taihan without authorization.
LS: "Protecting national core technology" vs. Taihan: "Trillion-won damage claim is absurd"
Following the police findings, the two sides remain on parallel tracks with no sign of compromise.
LS Cable has framed the incident as a "theft of national core technology" and signaled a hardline response. "Submarine cables are the foundation of Korea's industrial competitiveness and a core technology built up over decades through the dedication of our employees and massive investment," the company said. "To protect the industrial ecosystem, we will respond firmly and on principle to acts of technological infringement." LS Cable claimed the technology theft caused damages amounting to hundreds of billions of won and made clear its intention to pursue legal action, including civil litigation seeking damages.
Taihan expressed strong regret over the police conclusion and flatly denied the allegations. "We never used another company's trade secrets in the construction of our No. 1 submarine cable plant in Dangjin," Taihan said. "The mere fact that the participating contractors are the same as those used by another company cannot serve as grounds for claiming trade secrets were acquired."
Taihan emphasized that it has successfully produced and delivered submarine cables on multiple occasions since 2009, and that its technical understanding is high enough that it continuously designs its own plant blueprints — meaning it has no reason to copy a competitor's technology. "The total construction cost of the Dangjin No. 1 plant itself is around 220 billion won, so the other side's claim of trillion-won damages is absurd," the company added. "We will faithfully argue the legal issues surrounding trade-secret status in the remaining judicial process and clearly establish our innocence."
Ball now in prosecutors' court… global market impact in focus
The industry is watching closely for the outcome of the prosecution's investigation and the ensuing court battle. With police having referred the case with a recommendation for indictment, prosecutors will now decide whether to formally indict Taihan based on the investigative record. If the court ultimately finds Taihan liable, the case is expected to go beyond criminal punishment and trigger large-scale civil litigation that could reshape the domestic cable industry.
Above all, the biggest question is how the case will affect the global competitiveness of "K-cable." Demand for ultra-high-voltage submarine cables has entered an explosive "super cycle" amid the recent buildout of AI data centers and the global shift to renewable energy. With both companies staking their futures on global orders at this critical juncture, the outcome of the legal battle is expected to have a significant impact on their international market positions and credibility.
