A man walks toward Toshiba Corp's headquarters in Tokyo.

Tokyo - Tokyo police on Thursday arrested a man suspected of sharing proprietary data from technology company Toshiba Corp with a South Korean company, local media reported.

The 52-year-old man had access to the data when he worked as an engineer at SanDisk Corp, which produces memory chips jointly with Toshiba, police told the Kyodo News agency.

The man allegedly acquired research data on Toshiba's NAND flash memory in 2008 and provided it to his new employer SK Hynix Inc after leaving SanDisk later that year, according to the report.

The police acted after Toshiba and SanDisk filed a criminal complaint, the report said.

NAND flash memory used in products such as smartphones and tablets is a key product for Toshiba, the second-largest NAND memory producer after South Korea's Samsung Electronics Co.

In 2004, Toshiba filed a patent infringement suit against SK Hynix over NAND technologies, seeking an injunction against the sale of NAND memory by its Japanese unit.

In 2006, Tokyo District Court ordered SK Hynix to stop the sales and pay 7.8 million yen (76 000 dollars) in damages to Toshiba.