South Korean prosecutors have raided the local offices of three foreign semiconductor firms as part of an antitrust investigation into alleged price-fixing of memory interface chips.
The Fair Trade Investigation Division of the Seoul Central District Prosecutors' Office conducted searches and seizures at the South Korean headquarters of China's Montage Technology (SHA:688008, HKG:6809), Japan's Renesas Electronics (TYO:6723) and U.S.-based Rambus. All three companies are suppliers of critical components to global memory companies Samsung Electronics (KRX:005930), SK Hynix (KRX:000660) and Micron Technology.
Together, all three suppliers account for over 93% of the global supply for memory interface chips, according to semiconductor platform IC&PCB Union on Thursday. These components are vital for the mass production of high-speed DDR4 and DDR5 RAM, which manage and accelerate data transfer speeds between processors and memory modules.
In a Hong Kong filing on Thursday, Montage Technology confirmed the on-site investigation, saying it is fully cooperating with the probe. Montage noted that its operations remain normal and no charges have been filed against the company or its employees.
South Korea is a vital market for Montage, accounting for more than half, or 2.93 billion yuan, of its overall 5.46 billion yuan revenue in 2025.
Alongside the disclosure, Montage issued a positive profit alert on Friday, forecasting that its group revenue for the first half of 2026 will rise 26.6% year over year to roughly 3.34 billion yuan. It also projects first-half net profit to jump between 63.9% and 81.2% to a range of 1.9 billion to 2.1 billion yuan, driven by booming global demand for AI infrastructure.
To stabilize its valuation, Montage also announced that its Chairman and CEO Yang Chonghe has proposed an A-share buyback program valued between 300 million yuan and 600 million yuan.
Renesas, Rambus, Samsung, and SK Hynix have not yet publicly commented on the investigation.has reached out to the companies for comment.
In late-afternoon trading in Shanghai, Montage's shares fell nearly 10%, while its Hong Kong shares tumbled almost 6%. Renesas plunged nearly 8% in Tokyo.