Shares of Nvidia supplier UniMicron Technology plunged after Taiwanese prosecutors investigated the company over allegations that it falsely labeled the origin of its printed-circuit boards.

UniMicron's Taipei-listed shares sunk 10% in early Monday trading to 999 New Taiwan dollars, equivalent to US$31.57.

UniMicron allegedly shipped its China-made PCBs back to Taiwan and relabeled them as "Made in Taiwan," the Taoyuan District Prosecutors Office said Saturday.

Investigators raided UniMicron's headquarters and a plant in Taoyuan on Friday and questioned 14 employees, including the general manager and deputy general manager of its PCB business, prosecutors said.

Prosecutors said there were strong grounds to suspect the 14 defendants of committing the alleged offenses and set bail ranging from NT$300,000 to NT$15 million.

UniMicron confirmed the investigation in an exchange filing Friday and said the probe had no significant impact on its operations or financials.

UniMicron makes high-end PCBs, which provide the physical and electronic connections in AI servers. It is also one of a small number of manufacturers of high-end substrates using Ajinomoto Build-up Film, an insulating material that helps connect advanced chips to larger circuit boards. ABF substrates are critical to the production of many advanced chips.