Unauthorized Access at Consolidated Subsidiaries (Second-Tier Subsidiaries) and the Potential Leakage of Personal Information
株式会社たまのや and 株式会社喜月堂セレオ, both consolidated subsidiaries (sub-subsidiaries) of the filing company
The official websites of たまのや and 喜月堂セレオ, and the たまのや web forms for inquiries, information requests and consultation reservations
The exploitation of vulnerabilities in the website systems used on the official websites of たまのや and 喜月堂セレオ
No amount was disclosed. The impact on consolidated results is immaterial.
The impact on consolidated results is immaterial. If any matters arise that require disclosure under timely disclosure rules, they will be announced promptly.
Related procedures
Report to the Personal Information Protection Commission and consultation with the police
Personal Information Protection Commission and police
Company response
A forensic investigation by an external investigation firm. The name of the firm, the chairperson and the establishment date were not disclosed.
Updating the core system, imposing strict access restrictions on the administrative interface, continuously monitoring the systems, and reviewing the maintenance and operation structure
Customers who may have experienced personal information leakage will be contacted individually in due course. The systems will be continuously monitored and the maintenance and operation structure will be reviewed to prevent recurrence.
If any matters arise that require disclosure under timely disclosure rules, they will be announced promptly.
| Item | Details |
|---|---|
| Event name | Unauthorized Access at Consolidated Subsidiaries (Second-Tier Subsidiaries) and the Potential Leakage of Personal Information |
| Date of occurrence | Unauthorized access was confirmed on 10 September 2026 at たまのや and on 11 September 2026 at 喜月堂セレオ. |
| Date recognized / date notice received | The dates on which unauthorized access was confirmed were 10 September 2026 at たまのや and 11 September 2026 at 喜月堂セレオ. |
| Subject Entity | 株式会社たまのや and 株式会社喜月堂セレオ, both consolidated subsidiaries (sub-subsidiaries) of the filing company |
| Target Locations / Products | The official websites of たまのや and 喜月堂セレオ, and the たまのや web forms for inquiries, information requests and consultation reservations |
| Cause | The exploitation of vulnerabilities in the website systems used on the official websites of たまのや and 喜月堂セレオ |
| Amount of Impact on Business Performance | No amount was disclosed. The impact on consolidated results is immaterial. |
| Impact on Earnings Forecast | The impact on consolidated results is immaterial. If any matters arise that require disclosure under timely disclosure rules, they will be announced promptly. |
| Type of litigation or proceeding | Report to the Personal Information Protection Commission and consultation with the police |
| Court or authority | Personal Information Protection Commission and police |
| Investigation structure | A forensic investigation by an external investigation firm. The name of the firm, the chairperson and the establishment date were not disclosed. |
| Measures to prevent recurrence | Updating the core system, imposing strict access restrictions on the administrative interface, continuously monitoring the systems, and reviewing the maintenance and operation structure |
| Outlook | Customers who may have experienced personal information leakage will be contacted individually in due course. The systems will be continuously monitored and the maintenance and operation structure will be reviewed to prevent recurrence. |
| Planned follow-up disclosure | If any matters arise that require disclosure under timely disclosure rules, they will be announced promptly. |
Items this document does not state (11)
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.The exploitation of vulnerabilities in the website systems used on the official websites of たまのや and 喜月堂セレオ.