McMillan Metro, P.C. suffered a data breach caused by external system hacking between September 21–24, 2021, compromising the personal information of 1,728 individuals, including at least one Maine resident. The breach was discovered nearly a year later on August 11, 2022, with notifications to affected parties issued on November 7, 2022. The incident involved unauthorized access to sensitive data, though the exact nature of the exposed information (e.g., financial, medical, or personally identifiable details) was not explicitly detailed in the report. The delayed detection and response suggest potential vulnerabilities in the company’s cybersecurity monitoring and incident response protocols. The breach highlights risks associated with third-party intrusions, emphasizing the need for robust defensive measures to prevent similar future incidents.