NTT West group call-centre data theft
Add to my breach checkMade public · 9,280,000 people
What leaked7
Replaceable
- Card number
Hard to replace
- Mobile number
- Home or delivery address
Permanent
- Date of birth
- Full name
- Gender
- Partial date of birth or age
- Card number81 records from two client companies
- Date of birthin some records · NTT West's own customers
- Mobile numberphone number · landline or mobile
- Genderin some records
- Partial date of birth or ageage, in some records
To-dos3 · about 30 min in all
What happened next25 events
Response: 14 events
Back to latest- The contractor, NTT Marketing Act ProCX: no secondary harm, such as unauthorised use of customer information, confirmed so far
- The president and CEO stepped down at the end of March 2024, taking responsibility for the group company's leak of customer data
- Announced group-wide information-security measures based on the committee's findings
- Published the in-house investigation committee's report · with outside experts; the 2022 check had altered export logs and given the client false answers
- Began sending letters to people whose data could not be linked to a client
9 more
- Count revised to 9.28 million customers of 69 clients; 1.17 million could not be linked to any client
- Opened an inquiry line for clients' customers
- Opened a dedicated call centre for NTT West customers
- Published an apology to customers
- NTT West announced that about 1.2 million of its own customers' records were among the stolen data
- ProCX and NTT Business Solutions announced that a former temp worker had taken about 9 million customer records of 59 clients
- After a police investigation of NTT Business Solutions, ProCX admitted the data theft and reported the leak to the client that had raised it
- Blocked writing data from maintenance terminals to USB memory
- After a client asked in April 2022 whether its customer data had leaked, ProCX and NTT Business Solutions told it in July 2022 that no leak was found
- Company
- NTT West
- When it happened
- –
- Company detected it
- Made public
- Notice
- Leak confirmed
- Affected
- 9,280,000 people · customers and residents of 69 client companies and local governments; ProCX December 19, 2023, PPC: about 9.28 million
How the facts developed
- Revised to 9.28 million records of 69 clients; 1.17 million could not be linked to a client and were notified by letter from February 2024
- About 9 million records of 59 clients announced; NTT West's own customers about 1.2 million
Sources
- 個人情報保護委員会 regulator (opens in a new tab)checked October 22, 2026
- NTTマーケティングアクトProCX・NTTビジネスソリューションズ company notice, (opens in a new tab)checked October 22, 2026
- NTTマーケティングアクトProCX・NTTビジネスソリューションズ company notice, (opens in a new tab)checked October 22, 2026
- NTTマーケティングアクトProCX・NTTビジネスソリューションズ company notice, (opens in a new tab)checked October 22, 2026
- NTT西日本 company notice, (opens in a new tab)checked October 22, 2026
- Ministry of Internal Affairs and Communications regulator (opens in a new tab)checked October 22, 2026
- 日本経済新聞 press (opens in a new tab)checked October 22, 2026
- piyolog press (opens in a new tab)checked October 22, 2026
- NTT西日本 company notice, (opens in a new tab)checked October 23, 2026