HHS OCR report · 2023
University of Michigan data breach
OCR report facts
- Covered entity
- University of Michigan
- Entity type
- Healthcare Provider
- State
- Michigan
- Individuals affected
- 61,033
- Submission date
- Oct 23, 2023
- Type of breach
- Hacking/IT Incident
- Location of breached information
- Network Server
- Business associate present
- No
- Status
- Archive (closed)
OCR description
The covered entity (CE), The University of Michigan, reported that it experienced a ransomware incident that affected the protected health information (PHI) of 61,033 individuals. The PHI involved included names, addresses, dates of birth, drivers’ license and Social Security numbers, government-issued identification numbers, claims and financial information, diagnoses and conditions, medications, and other treatment information. The CE notified HHS, affected individuals, the media, and poste...
Text as published on the HHS OCR breach portal.
Frequently asked questions
How many people were affected by the University of Michigan data breach?
The report to HHS OCR lists 61,033 individuals affected.
When was it reported to HHS?
It was submitted to HHS OCR on Oct 23, 2023.
What type of breach was it?
The OCR portal lists the type of breach as Hacking/IT Incident, with the breached information located in: Network Server.
Is the investigation still open?
No. The report is in the OCR portal archive, which holds reports where OCR has closed its review.
Is a breach notice letter from University of Michigan legitimate?
This site cannot verify letters. Check the sender against the organisation's official website and the HHS OCR breach portal, and avoid calling numbers or clicking links only listed in an unexpected message. See our guide on what to do after a data breach notice.
Source: HHS OCR Breach Portal, OCR export October 2026. Network USA is not affiliated with HHS or University of Michigan.