A Japanese court Friday sentenced a former employee of SoftBank Corp. to two years in prison, suspended for four years, and a 1 million yen ($7,300) fine over leaking the company's 5G network technology information to Rakuten Mobile Inc.

The Tokyo District Court convicted Kuniaki Aiba, who had worked at SoftBank Group Corp.'s mobile phone service subsidiary but moved to Rakuten.

Aiba was arrested in January last year on suspicion of violating Japan's unfair competition prevention laws. He had allegedly transferred data related to SoftBank's 5G technology to his email account. He joined Rakuten Group Inc.'s wireless unit soon after leaving SoftBank in December 2019.

Presiding Judge Masakazu Kamakura said of the ruling that Aiba leaked the information for his own benefit at Rakuten Mobile, describing his motives as "selfish and malicious."

But when explaining the granting of a suspended sentence, Kamakura said that the case for Aiba purposefully seeking an unfair advantage over SoftBank was "not strong" enough.

While the defense claimed Aiba was innocent as the leaked information did not constitute trade secrets, Kamakura refuted the argument, saying it did because the data was important and confidential to SoftBank.

According to Rakuten, Aiba had quit the company as of Jan. 15, 2021.

In September 2020, Rakuten started offering unlimited data services using ultrafast 5G networks for 2,980 yen per month, much lower than other major mobile phone service operators in Japan amid intensifying competition.