Mercadien, P.C. CPAs disclosed a cybersecurity incident involving potential unauthorized access to its systems. While the investigation is ongoing, client information may have been exposed.
Mercadien’s Data Breach Investigation
On December 1, 2025, Mercadien, P.C. CPAs—a professional accounting and advisory firm, publicly disclosed a potential data breach affecting its systems. In a letter to clients, the company stated that it had detected signs of a security incident and launched an investigation into unauthorized access.
Although the full scope of the breach is still being determined, Mercadien made the decision to inform clients proactively. The company stated that it values transparency and wanted to notify affected individuals as early as possible, even before all technical analysis had concluded. This preemptive approach suggests that sensitive client information, potentially including financial or personal data, may have been accessed.
The incident prompted Mercadien to engage third-party forensic cybersecurity professionals to investigate the situation, secure their systems, and determine what data, if any, had been compromised. The forensic review is ongoing, and Mercadien has not yet confirmed exactly what information was involved or how many individuals were affected.
For client convenience, Mercadien has also published a formal notice on its website (www.mercadien.com/notice) and set up a toll-free number to answer questions. The firm acknowledges the seriousness of the situation and expressed regret for any inconvenience caused.
As of now, Mercadien has not offered credit monitoring services, likely due to the preliminary stage of the investigation. However, they have pledged to provide updates as more details become available. The incident underscores the growing threat of cybersecurity attacks even against financial and advisory firms that handle sensitive data on behalf of clients.
In light of these developments, clients who received a notice or suspect they may be affected should stay alert, monitor their accounts, and consider their legal rights.
When Did This Breach Occur?
Mercadien discovered the potential security incident on or before December 1, 2025, the date the notification letter was issued. The exact date of the breach has not yet been publicly disclosed, as the investigation is ongoing.
What Information Was Breached?
As of the December 1, 2025 notification, Mercadien has not confirmed the specific categories of data affected. However, given the firm’s role in financial services, the following types of data may have been involved:
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Full names
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Contact information (addresses, phone numbers, email addresses)
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Financial records
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Tax-related documents
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Social Security numbers
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Personal identification details
What You Can Do
If you received a notification from Mercadien, here are proactive steps to protect yourself:
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Stay Informed: Regularly check www.mercadien.com/notice for updates about the breach.
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Monitor Your Accounts: Watch for unusual activity in bank, investment, and credit accounts.
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Check Your Credit Reports: Request free copies from Equifax, Experian, and TransUnion and look for any unauthorized inquiries or accounts.
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Place a Fraud Alert or Freeze: Consider placing a fraud alert or credit freeze to prevent new accounts from being opened in your name.
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Document Everything: Keep records of any suspicious activity in case you need to file a report or claim.
Class Action U exists to help people understand their rights and take action. If you’ve been affected by this breach, we can connect you with legal professionals who specialize in holding companies accountable for data mishandling.
File a Data Breach Lawsuit Against Mercadien
If you received a breach notification from Mercadien, or if your personal or financial information may have been exposed, you could be eligible to join a class action lawsuit. Data breach lawsuits allow affected individuals to seek compensation for stress, time, risk, and any resulting damages.
Financial advisory firms have a duty to protect client information. When that trust is broken, legal action may be necessary to ensure accountability. Even if no misuse of your information has yet occurred, the exposure itself may justify compensation.
Contact us at Class Action U, where we’ll connect you with a lawyer skilled in class action lawsuits. If you’ve been contacted about this breach, received notice, or discovered you were impacted, fill out our quick, easy, and secure form to sign up. There is no cost to reach out to our legal partner and no obligation after speaking with someone from our team.
