BayMark Health Services discloses data breach affecting 16,548 Americans

On March 20, 2025, BayMark Health Services, Inc.—a major provider of medication-assisted treatment for substance use disorders—discovered a significant data breach that had occurred on two separate dates: September 24, 2024 and October 14, 2024. According to official disclosures, the breach affected a total of 16,548 individuals across the United States. Of these, 11,623 were residents of Texas, 5,460 in New Hampshire, 2,263 in Washington State, 481 in Maine, and 2 in Massachusetts.

The breach was the result of a ransomware attack claimed by the RansomHub group, who announced on the dark web that they had obtained 1.5 TB of BayMark’s data and threatened to publish it within 36-37 days. The stolen data included both personally identifiable information (PII) and protected health information (PHI).

Information Exposed:

• Names of individuals
• Social Security Number Information
• Driver’s License numbers
• Health Insurance Information
• Medical Records
• Full Dates of Birth

The breach was reported to multiple government agencies, including the California Attorney General, Maine Attorney General, Massachusetts Attorney General, Texas Attorney General, Vermont Attorney General, and the U.S. Department of Health and Human Services. The company notified affected consumers by U.S. mail on May 2, 2025.

BayMark Health Services' response

After discovering the breach, BayMark Health Services took steps to notify affected individuals by written letter via U.S. mail. The company also reported the incident to state and federal authorities, as required by law. While the specific details of the company’s response plan have not been disclosed, individuals whose information was involved should remain vigilant.

Given the nature of the attack—ransomware with a threat to publish sensitive data—affected individuals should:

• Monitor their credit reports and financial accounts for any unusual activity.
• Consider placing a fraud alert or credit freeze with the major credit bureaus.
• Watch for suspicious emails or phone calls that could be phishing attempts related to the breach.
• Review any correspondence from BayMark Health Services for information about resources such as credit monitoring or identity theft protection (if offered).