Samsung Electronics building in Seocho-dong, southern Seoul / Yonhap

Prosecutors have indicted four current and former employees of electronics giant Samsung Group on charges of stealing highly valued semiconductor technologies from the Korean conglomerate and leaking them to overseas firms, officials said Thursday.

The Seoul Central District Prosecutors Office has indicted two Samsung Engineering researchers and two other former Samsung engineers with physical detention on charges of violating the unfair competition prevention act and the industrial technology protection act, the officials said.

One of the former employees, who worked in the semiconductor field, was accused of receiving an operation manual and a blueprint for an ultrapure water system and other key technology data from two Samsung Engineering workers and leaking them in August 2018 while he was trying to find a new job at a Chinese semiconductor consulting firm.

After getting a job at a Chinese firm, the engineer allegedly used the stolen materials to place an order for an ultrapure water system.

Ultrapure water is water purified of any ions, organic matter or microbe to be used for cleansing in the semiconductor manufacturing process.

Samsung Electronics has invested over 30 billion won ($21.2 million) each year since 2006 to develop the ultrapure water system.

Prosecutors said the other former employee faces charges of leaking a computer file carrying a key foundry semiconductor technology of Samsung Electronics to semiconductor rival Intel while he worked for the Korean firm.

He was in the process of moving his job to Intel at that time, and accessed the firm's semiconductor technology data online and stole the file by taking photos, according to prosecutors. (Yonhap)