Overview
File review was completed on January 9, 2026; data included names with SSNs and/or medical information such as doctors, diagnoses, insurance, medicines, test results, images and treatment. Media reported ransomware group claims, which were not used as evidence. No total is given. The first-disclosure date is the earliest public document confirmed (California AG posting); no 2025 public disclosure was found in other state AG lists, HHS or company notices checked.
Timeline
- Occurred
- Discovered
- Disclosed
Organization response
Per the notice, the organisation investigated and contained the incident, notified individuals and offered monitoring or protective resources.
What you can do
Verify notices through official channels, avoid links in unexpected messages, do not provide credentials, and review credit reports and statements.
Sources
- California AG data breach report: MACT Health Board Inc.California Department of Justice, Office of the Attorney General · 2026-11-09
- MACT Health Board Patients Affected by November 2025 Ransomware Attack (HIPAA Journal)The HIPAA Journal · 2026-11-09
- Sample consumer notice filed with California AG (MACT Health Board Inc.)California Department of Justice, Office of the Attorney General · 2026-11-09