HHS OCR report ยท 2020
Northwestern Memorial HealthCare data breach
OCR report facts
- Covered entity
- Northwestern Memorial HealthCare
- Entity type
- Healthcare Provider
- State
- Illinois
- Individuals affected
- 55,983
- Submission date
- Aug 28, 2020
- 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), Northwestern Memorial Healthcare, reported that its business associate (BA) experienced a ransomware attack affecting the electronic protected health information (ePHI) of approximately 55,983 individuals. The ePHI involved included names, addresses, and treatment information. The CE notified HHS, affected individuals, the media, and provided substitute notice.
Text as published on the HHS OCR breach portal.
Other reports by Northwestern Memorial HealthCare
| Covered entity | State | Entity type | Individuals | Submitted | Type of breach | Status |
|---|---|---|---|---|---|---|
| Northwestern Memorial HealthCare | IL | Healthcare Provider | 201,197 | Jun 25, 2021 | Hacking/IT Incident | Archive (closed) |
| Northwestern Memorial HealthCare | IL | Healthcare Provider | 2,813 | Dec 23, 2014 | Theft | Archive (closed) |
Frequently asked questions
How many people were affected by the Northwestern Memorial HealthCare data breach?
The report to HHS OCR lists 55,983 individuals affected.
When was it reported to HHS?
It was submitted to HHS OCR on Aug 28, 2020.
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 Northwestern Memorial HealthCare 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 Northwestern Memorial HealthCare.