Rakuten Mobile denied an employee shared confidential information obtained while working with SoftBank Corp, setting the stage for a legal battle between the rivals.

Yoshihisa Yamada, Rakuten Mobile director and president, stated an internal review is yet to find any evidence supporting SoftBank Corp’s claims a former employee provided information on its business to the Japanese newcomer.

“We are taking this matter very seriously and are fully committed to cooperating with the police in their investigation,” Yamada said.

Japanese police arrested the employee yesterday (12 January) as part of an investigation into whether competition laws had been broken.

The person stands accused of transferring the information prior to departing SoftBank Corp’s network construction division in December 2019.

SoftBank Corp threatened to take legal action against Rakuten Mobile, which it believes used the network information ahead of its launch as a full MNO in April 2020.