HHS OCR report · 2021
McLaren Health Care Corporation data breach
OCR report facts
- Covered entity
- McLaren Health Care Corporation
- Entity type
- Healthcare Provider
- State
- Michigan
- Individuals affected
- 64,600
- Submission date
- Jul 16, 2021
- Type of breach
- Hacking/IT Incident
- Location of breached information
- Network Server
- Business associate present
- Yes
- Status
- Archive (closed)
OCR description
The covered entity (CE), McLaren Health Care Corporation, reported that its business associate experienced a ransomware attack that affected the electronic protected health information (ePHI) of 64,600 individuals. The ePHI involved included names, addresses, dates of birth, drivers’ license numbers, Social Security numbers, diagnoses, clinical information, and other treatment information. The CE notified HHS, affected individuals, the media, and posted substitute notice on its website. In...
Text as published on the HHS OCR breach portal.
Frequently asked questions
How many people were affected by the McLaren Health Care Corporation data breach?
The report to HHS OCR lists 64,600 individuals affected.
When was it reported to HHS?
It was submitted to HHS OCR on Jul 16, 2021.
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 McLaren Health Care Corporation 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 McLaren Health Care Corporation.