Oak Valley Hospital District
Disclosed Sep 15, 20233 years ago284,629 affectedConfirmed
Oak Valley Hospital District, the covered entity (CE), reported that it experienced a cyber-attack that compromised the protected health information (PHI) of 284,629 individuals. The PHI involved included names, addresses, dates of birth, Social Security numbers, health insurance information, diagnoses, lab results, medications, and claims information. The CE notified HHS, affected individuals, the media, and posted substitute notice on its website. In response to the breach and OCR’s investigation, the CE revised its policies and procedures, retrained its workforce members, and implemented additional technical safeguards.
What is known
| People affected | 284,629 (as reported to HHS) |
|---|---|
| Disclosed | Sep 15, 2023 |
| Happened | Apr 21, 2023 |
| Attack | Hacking |
| Data exposed | Names, Health |
| Sector | Healthcare · US |
| Status | Confirmed |
Sources
| Source | |
|---|---|
| California Attorney General breach notice: Oak Valley Hospital Districtoag.ca.gov · Official notice | Official notice |
| HHS OCR breach report (archive, resolved): Oak Valley Hospital District (Healthcare Provider, CA)ocrportal.hhs.gov · Official notice | Official notice |
Notices filed
| Where | Filed | People |
|---|---|---|
| California AGresidents of CA | Sep 15, 2023 | |
| HHS archivetotal | Sep 15, 2023 | 284,629 |
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 284629 · backfill source
- 2026-09-25 · summary: empty to Oak Valley Hospital District, the covered entity (CE), reported that it experienced a cyber-attack that compromised the protected health information (PHI) of 284,629 individuals. The PHI involved included names, addresses, dates of birth, S · 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.