Back to the register

Group Health Cooperative of South Central Wisconsin

ArchivedSubmitted 04/08/2024

Updated 20 hours ago ()

State
WI
Covered entity type
Health Plan
Individuals affected
533,809
Business associate present
No
Type of breach
Hacking/IT Incident
Location of breached information
Network Server
First seen by InfoSec Signals
Sep 23, 2026
Last seen in OCR export
Oct 25, 2026

OCR description

The covered entity (CE), Group Health Cooperative of South Central Wisconsin, reported that it was the subject of a ransomware attack that affected the protected health information (PHI) of 533,809 individuals. The PHI involved included names, Social Security numbers, addresses, dates of birth and medial record numbers. The CE notified HHS, the affected individuals, the media, and provided substitute notice. In response to the breach, the CE provided complimentary credit monitoring services to the affected individuals and implemented additional administrative, technical, and security safeguards. Staff were retrained on the requirement to protect and secure PHI.

Change history

  • Sep 23, 2026Added to OCR's archive list

Source: HHS OCR Breach Portal, U.S. Department of Health and Human Services, Office for Civil Rights about this source

Records are reproduced as published; entity names and figures are OCR's.

Your cookie choices
We use essential cookies to run this site, and, only with your consent, an advertising cookie from Google to measure whether our ads lead to sign-ups and subscriptions. See our for details.