Insight Hospital and Medical Center Chicago, also known as Insight Chicago, detected unusual activity within its network in September 2025, which led to the discovery of a data breach. An investigation confirmed that an unauthorized individual accessed the network and certain files between August 22, 2025, and September 11, 2025. The company issued notices to affected individuals around February 25, 2026, confirming the incident.
The breach involved various types of sensitive patient data, including names, Social Security numbers, dates of birth, state-issued ID numbers, financial account information, treatment-related information, and health insurance information. The exact number of affected individuals has not been publicly disclosed by Insight Chicago, though notifications have been sent to patients. While ransomware groups made claims regarding data theft, Insight Chicago has not acknowledged these claims.
Details about this incident, including the full scope of individuals affected, may continue to emerge. Patients who received notices should review them carefully for specific information regarding the breach.