The communications ministry said Friday it will order NTT West Corp. to improve its business practices following a massive leak of confidential customer data to sales agents in violation of the law.
The ministry said an employee of NTT West-Hyogo Corp., a subsidiary of the regional telecom company, leaked more than 350,000 sets of data on subscribers to NTT West's and competing carriers' asymmetric digital subscriber line services between last August and October.
The order will be issued following a hearing by the Internal Affairs and Communications Ministry with NTT West.