What Happened?
Recently, Mid Michigan Medical Billing Service, Inc. (“MMMBS”) became aware of a security incident on its IT network. Upon detection, MMMBS launched an investigation with the assistance of third-party cybersecurity experts to determine the nature and scope of the incident. The investigation determined that an unauthorized third party gained access to MMMBS’s network and obtained access to certain files on March 27, 2025. MMMBS conducted a comprehensive review of the impacted data to determine what information was compromised and identified affected individuals. On January 5, 2026, MMMBS filed a notice with the Department of Health and Human Services and began sending notice letters to impacted individuals.