Personal Information Breach Caused by Unauthorized Access
ブックオフコーポレーション株式会社 (a consolidated subsidiary of the filing company)
Member management systems for BOOKOFF operations in Japan, including app members, online store members and web members. The affected services are BOOKOFF SUPER BAZAAR, BOOKOFF PLUS, BOOKOFF, the official BOOKOFF online store, あそビバ, BOOKOFF FASHION, BINGO, B・SPORTS, B・STYLE and Rehello by BOOKOFF (stores).
Unauthorized access by a third party. Specific details of the system configuration, vulnerabilities and attack methods have not been disclosed.
There is no impact on results for the first-quarter cumulative consolidated period. The amount of the impact on the consolidated earnings forecast for the fiscal year ending May 2027 is currently under review.
This event occurred after the end of the first-quarter consolidated accounting period, and has no impact on results for the first-quarter cumulative consolidated period. The timing of any other recognition has not been determined.
The impact on results is currently under review and has not been reflected in the consolidated earnings forecast for the fiscal year ending May 2027. We will promptly announce any revision to the earnings forecast or other developments.
Related procedures
Reporting to the Personal Information Protection Commission, consultation with the police, and cooperation with the investigation
Personal Information Protection Commission and police
Company response
An investigation into the cause is being conducted with the assistance of external experts. The establishment date and the chairman's name are Not disclosed.
Blocking communications from the source of the attack and routes used for unauthorized access, strengthening access controls and monitoring, conducting an emergency comprehensive inspection covering all systems and environments of the Group, implementing additional security measures, and establishing permanent measures to prevent recurrence.
We will contact affected members sequentially from 15 October 2026. We will continue investigating the cause and conducting an emergency comprehensive inspection of all systems and environments, and will implement additional security measures and permanent measures to prevent recurrence in cooperation with the relevant authorities and external experts.
We will promptly announce any new facts requiring disclosure or any revision to the earnings forecast.
| Item | Details |
|---|---|
| Event name | Personal Information Breach Caused by Unauthorized Access |
| Date of occurrence | Member information was obtained externally between 4 October 2026 and 6 October 2026. |
| Date recognized / date notice received | 6 October 2026 |
| Subject Entity | ブックオフコーポレーション株式会社 (a consolidated subsidiary of the filing company) |
| Target Locations / Products | Member management systems for BOOKOFF operations in Japan, including app members, online store members and web members. The affected services are BOOKOFF SUPER BAZAAR, BOOKOFF PLUS, BOOKOFF, the official BOOKOFF online store, あそビバ, BOOKOFF FASHION, BINGO, B・SPORTS, B・STYLE and Rehello by BOOKOFF (stores). |
| Cause | Unauthorized access by a third party. Specific details of the system configuration, vulnerabilities and attack methods have not been disclosed. |
| Amount of Impact on Business Performance | There is no impact on results for the first-quarter cumulative consolidated period. The amount of the impact on the consolidated earnings forecast for the fiscal year ending May 2027 is currently under review. |
| Accounting period in which recognized | This event occurred after the end of the first-quarter consolidated accounting period, and has no impact on results for the first-quarter cumulative consolidated period. The timing of any other recognition has not been determined. |
| Impact on Earnings Forecast | The impact on results is currently under review and has not been reflected in the consolidated earnings forecast for the fiscal year ending May 2027. We will promptly announce any revision to the earnings forecast or other developments. |
| Type of litigation or proceeding | Reporting to the Personal Information Protection Commission, consultation with the police, and cooperation with the investigation |
| Court or authority | Personal Information Protection Commission and police |
| Investigation structure | An investigation into the cause is being conducted with the assistance of external experts. The establishment date and the chairman's name are Not disclosed. |
| Measures to prevent recurrence | Blocking communications from the source of the attack and routes used for unauthorized access, strengthening access controls and monitoring, conducting an emergency comprehensive inspection covering all systems and environments of the Group, implementing additional security measures, and establishing permanent measures to prevent recurrence. |
| Outlook | We will contact affected members sequentially from 15 October 2026. We will continue investigating the cause and conducting an emergency comprehensive inspection of all systems and environments, and will implement additional security measures and permanent measures to prevent recurrence in cooperation with the relevant authorities and external experts. |
| Planned follow-up disclosure | We will promptly announce any new facts requiring disclosure or any revision to the earnings forecast. |
Items this document does not state (10)
These are items the company does not state in this document. We do not leave them blank, nor fill them in from other sources or by inference.
The reasons the company gives
The company's own explanation, not something inferred from the numbers.A third party gained unauthorized access to BOOKOFF CORPORATION's member management system and obtained member information externally. Specific details of the system configuration, vulnerabilities and attack methods have not been disclosed.