Dai-ichi Mutual Life Insurance Co. said Friday a customer list containing personal data on 88 of its policyholders in Asao Ward, Kawasaki, has been leaked.
The list, which includes the names, addresses, types of policies purchased and the amount of the customers' coverage, was mailed to the homes of some of the policyholders, it said.
After a number of the affected policyholders contacted the insurer about the incident on Aug. 30, the company investigated and found that 58 of them had received the list as of Friday.
But this wasn't the first time some of them had their privacy invaded. Of the 88 customers on the list, the data of 54 were leaked in a similar incident last year. At that time, 44 of them were mailed the list.
Dai-ichi said the list was not made by the company and that it has not determined how the leak happened.