Mark L. Karno & Associates Data Breach Investigation

Recently, Mark L. Karno reported to the Attorney General of Maine that it had experienced a data breach in which sensitive personal identifiable information in its care may have been compromised. According to the breach notice, on September 17, 2024, Mark L. Karno discovered suspicious activity potentially related to an employee email account.¹ As a result, Mark L. Karno launched an investigation to determine the nature of the incident.

Through its investigation, Mark L. Karno confirmed that the sensitive personal information in the affected email account may have been accessed by an unauthorized third party during the breach.¹ As a result, Mark L. Karno began a review of the data to determine what information had been impacted as well as identify the specific individuals affected. On August 7, 2025, Mark L. Karno completed this review. As of October 13, 2025, the type of information impacted in the breach has not been made publicly available by Mark L. Karno.¹ However, according to Maine state reporting guidelines, “personal information” can include the following types of information:

• Name
• Social Security number
• Driver’s license number or State ID card number
• Account number or credit or debit card number
• Account passwords, PINs, and other access codes

On October 9, 2025, Mark L. Karno began mailing data breach notification letters to impacted individuals. Based on the breach notice being sent to Maine residents, Mark L. Karno is providing affected individuals with a list of the specific types of sensitive information impacted and complimentary credit monitoring services.¹ A link to the letters that Mark L. Karno filed with the Attorney General of Maine is below.