Monogatari Corporation (Yakiniku King) Data Breach
The Monogatari Corporation, operator of the popular Japanese restaurant chain Yakiniku King, announced on October 5, 2026, that an unauthorized party had breached the member management system of the official Yakiniku King smartphone app.
Exposed Data Types
4- Names
- Email addresses
- Phone numbers
- User IDs
About This Breach
Forensic investigations confirmed that 10,788,963 member records, nearly the entire registered user base, were exfiltrated.
Exposed information consisted of member ID numbers, full names, email addresses, and telephone numbers. The company verified that login passwords, dates of birth, genders, postal codes, dining histories, and credit card details were not stored in the compromised database.
Verification and editorial method
LeakData compares the incident name, date, affected-record count, and exposed data types with accessible sources. Unverified fields are not presented as facts, and records are updated when new evidence becomes available.
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