Mercadien PC Data Breach Exposes Sensitive Personal & Financial Info

On Nov. 7, 2025, Mercadien PC Certified Public Accountants, a financial services and accounting firm experienced a significant data breach that may have affected personally identifiable information (PII) belonging to clients and individuals associated with the firm.

According to disclosures filed with the Maine Attorney General and the Massachusetts Attorney General, the breach involved unauthorized access to a range of personal and financial data.

The types of leaked data may include names, addresses, dates of birth, driver's license/Government ID numbers, Social Security numbers, financial account information, usernames and passwords, IRS pin numbers, and/or payment card information. This data is considered personally identifiable information (PII), and in some cases, financial data that could be used for identity theft or fraud.

The breach was publicly disclosed in Maine on Dec. 31, 2025, and in Massachusetts on Dec. 24, 2025. The company also posted a Notice of Data Breach on its website and began notifying impacted individuals by mail. The total number of people affected has not yet been finalized, but the scope of the breach is considered broad, given the types of data involved.

Mercadien PC Certified Public Accountants' response

Following the discovery of the breach, Mercadien PC Certified Public Accountants took several immediate steps to investigate and contain the incident. The firm launched an internal investigation, engaged a national cybersecurity firm to assess the scope of the breach, and notified law enforcement. The company has also taken steps to strengthen its security posture and mitigate the potential impact on affected individuals.

If you believe your personal information may have been compromised in this breach:

• Carefully review any notice or communication you receive from Mercadien or a company that does business with Mercadien.
• Monitor financial accounts and credit reports for signs of identity theft.
• Consider placing fraud alerts or credit freezes with the major credit bureaus.
• Be cautious of unsolicited emails or phone calls requesting personal information.

To support those whose information may have been compromised, Mercadien has set up a dedicated call center at 855-403-1825, available Monday through Friday from 9 a.m. to 9 p.m. ET.