Health Net of California
Disclosed Mar 25, 20215 years ago550,828 affectedConfirmed
The covered entity (CE), Health Net of California, reported that its business associate (BA) experienced a cyber-attack that affected the electronic protected health information (ePHI) of 550,828 individuals. The ePHI involved included names, addresses, dates of birth, health insurance information, diagnoses, and other treatment information. The CE notified HHS, affected individuals, the media, and provided substitute notice. Following the breach, the CE provided complimentary credit monitoring services to affected individuals and terminated its business relationship with the BA.
What is known
| People affected | 550,828 (as reported to HHS) |
|---|---|
| Disclosed | Mar 25, 2021 |
| Happened | Jan 7, 2021 |
| Attack | Hacking |
| Data exposed | Names, Health |
| Sector | Healthcare · US |
| Status | Confirmed |
Sources
| Source | |
|---|---|
| California Attorney General breach notice: Health Net of Californiaoag.ca.gov · Official notice | Official notice |
| HHS OCR breach report (archive, resolved): Health Net of California (Health Plan, CA)ocrportal.hhs.gov · Official notice | Official notice |
Notices filed
| Where | Filed | People |
|---|---|---|
| California AGresidents of CA | Mar 25, 2021 | |
| HHS archivetotal | Mar 25, 2021 | 550,828 |
History of this record
- 2026-09-25 · attack: unknown to hacking · backfill source
- 2026-09-25 · data_types: [] to ["names","health"] · backfill source
- 2026-09-25 · records_basis: empty to hhs · backfill source
- 2026-09-25 · records: empty to 550828 · backfill source
- 2026-09-25 · summary: empty to The covered entity (CE), Health Net of California, reported that its business associate (BA) experienced a cyber-attack that affected the electronic protected health information (ePHI) of 550,828 individuals. The ePHI involved included name · backfill source
- 2026-09-25 · added · backfill source
First seen 2026-09-25 (California AG), confirmed by California AG. Record counts are as reported. Not legal advice.