Mitsuuroko Vessel: customer data of 5,259 Mitsuuroko Hikari subscribers, used to check billing statements, was mistakenly sent to one corporate client

1. 2021-07-29

   Around 18:00, when emailing a billing statement to a corporate client of Mitsuuroko Hikari, it also mistakenly sent the customer data used to check the statement. [1]

2. 2021-07-31

   It recognized the leak and asked the recipient to delete the data. [1]

3. 2021-08-02

   Around 10:00, it confirmed all the data had been deleted and had not reached any third party. [1]

4. 2021-08-10

   It submitted a report to the Kanto Bureau of Telecommunications of the Ministry of Internal Affairs and Communications. [1] [2]

5. 2021-08-19

   It announced the case. [1] [2]

Names, addresses, phone numbers and billed amounts of 5,259 Mitsuuroko Hikari subscribers. [1]