Overview
About 150,000 entries contained one or more identifying fields; about 120,000 email entries are a subset. Roughly 1.68 million contained only non-identifying fields. These approximate record counts are not people totals and are not added. No card information was included. The credential-theft route is unknown; subsequent PHP reviews or form changes do not establish the entry cause.
Timeline
- Occurred
- Discovered
- Disclosed
Unauthorized access to development cloud.
Initial public disclosure.
Nikkei HR updated individualized-notice progress.
Organization response
Nikkei invalidated cloud credentials, reported to Japan’s data-protection authority on October 11 and began individual confirmed-victim notices on October 21.
What you can do
Watch for impersonation and consult individualized notices and official support channels.
Sources
- Personal Information Leak Due to Unauthorized AccessNikkei Inc. · 2026-11-09
- 日経HR 第2報: 個別通知状況株式会社日経HR · 2026-11-09