The logo of Samsung Electronics is seen at the company's store in Seoul, April 15. Reuters-Yonhap

Prosecutors raided the headquarters of Samsung Electronics over suspicions employees of a local robotics company gained unfair profits using insider information when it was acquired by the chipmaker, legal sources said Thursday.

Investigators from the Seoul Southern District Prosecutors Office carried out a search-and-seizure operation at the chipmaker's headquarters in Suwon, south of Seoul, the sources said.

Financial authorities have referred a total of 16 people, including the head of the local industrial robot maker, Rainbow Robotics, and the firm's chief financial officer, to the prosecution for alleged violation of the Capital Markets Act.

They are suspected of gaining around 3 to 4 billion won ($2.6 million) worth of unfair profits using insider information, when Samsung was acquiring the company's shares from 2022 to 2024.