Eisner Advisory Group Data Breach Class Action Investigation

At Console & Associates, our data breach lawyers are closely examining the recent Eisner Advisory Group data breach. This data breach was disclosed following a cyber security incident at Eisner Advisory Group, which may have affected individuals, potentially exposing sensitive personal identifiable information.

What Happened?

A recent report from the Montana Attorney General's office states that the Eisner Advisory Group data breach occurred due to a cyber security incident that allowed unauthorized access to their computer network.

The security breach occurred between September 4, 2023, and September 23, 2023, when unidentified parties gained access to portions of EisnerAmper's systems. The company detected suspicious activity in September 2023 and immediately launched an investigation to determine the extent of the network intrusion.

After a comprehensive review that concluded in February 2025, EisnerAmper determined that the following types of information may have been compromised:

• Full legal names
• Home and mailing addresses
• Social Security numbers
• Driver's license information
• State-issued identification numbers
• Passport numbers
• Birth dates
• Banking and financial account details
• Payment card information
• Personal medical information
• Health insurance policy details

Data breach letters were sent out by Eisner Advisory Group on April 8, 2025, informing affected individuals about the nature of the incident and the specific categories of their personal data that may have been exposed.

Steps To Take If You Were Affected By A Data Breach

1. Monitor all accounts and credit reports closely
   1. Set up alerts for suspicious activity
   2. Review all financial statements thoroughly
   3. Request free credit reports and examine them for unauthorized entries
      
      
2. Consider freezing your credit
   1. Contact all three major credit bureaus to place a freeze
   2. Understand this prevents new accounts from being opened in your name
   3. Remember to temporarily lift the freeze when applying for legitimate credit
      
      
3. Look out for phishing attempts using information from the Eisner Advisory Group data breach
   1. Be wary of unexpected emails or messages claiming to be from Eisner Advisory Group
   2. Don't click on suspicious links or download unexpected attachments
   3. Verify all communications through official channels
      
      
4. Change passwords for affected accounts
   1. Create strong, unique passwords for each account
   2. Use a combination of letters, numbers, and special characters
   3. Consider using a password manager for better security
      
      
5. Enable two-factor authentication where possible
   1. Add this extra layer of security to all important accounts
   2. Use authenticator apps rather than SMS when available
   3. Keep backup codes in a secure location

For more detailed guidance, explore our “Guide for Victims of a Data Breach” to better understand measures you can take to protect yourself after a data breach.

Eisner Advisory Group Overview

Eisner Advisory Group LLC operates as EisnerAmper LLP, a substantial accounting and professional services organization headquartered in New York City. The firm delivers comprehensive financial services including audit, tax, advisory, and specialized consulting across multiple industry sectors. With a workforce of approximately 4,000 professionals and estimated annual revenue of $472 million, EisnerAmper maintains a significant presence in the professional services landscape.

The company operates through multiple office locations throughout the United States and has established an international footprint to serve its global clientele. EisnerAmper's business model centers on providing specialized expertise to diverse sectors including financial services, real estate, healthcare, and technology. Their client portfolio encompasses corporations, not-for-profit organizations, and high-net-worth individuals requiring complex financial and advisory services.

EisnerAmper's organizational structure enables it to deliver specialized knowledge across various accounting and advisory disciplines while maintaining industry-specific teams to address sector-specific challenges and regulatory requirements.

Eisner Advisory Group Data Breach Victims Have Rights - Don’t Wait to Act

How do you know that you were affected by the Eisner Advisory Group data breach? Usually victims receive a NOTICE OF DATA BREACH in the mail, but the impact of a breach can be felt long before notices are sent to those affected. This can be in the form of fraudulent financial activity and other forms of identity theft.

If you believe you were affected, we encourage you to reach out to our data breach law firm for legal assistance through a no-cost consultation about your situation. We will review your eligibility to file a data breach class action lawsuit and discuss your legal rights and any compensation that may be available to you.

Complete our confidential contact form below and a member of our legal team will be in touch.