Leonard, Mulherin & Greene Data Breach Lawsuit Investigation
Did you receive a letter from Leonard, Mulherin & Greene? The Massachusetts accounting and consulting firm has disclosed a cyber-incident that may have exposed sensitive data for more than 3,300 people. Find out how to protect yourself and whether you qualify to file a claim.
What Happened?
On December 2, 2024, Leonard, Mulherin & Greene, PC (“LMG”) noticed suspicious activity in one of its email accounts. A forensic investigation revealed that an unauthorized party had gained access to portions of the firm’s network around November 21, 2024. After eight months of data review, LMG confirmed on August 7, 2025, that certain files containing client and employee information had been impacted.
Information Exposed
The data potentially accessed varies by individual but may include:
- Full name
- Social Security number
- Financial account information
Who Is Affected?
LMG reported the breach to the Maine Attorney General on August 14, 2025, listing approximately 3,300 affected individuals. Notification letters began mailing on August 13, 2025, to everyone whose data was determined to be at risk.
Your Next Steps
LMG is offering 12 months of complimentary credit monitoring. Even if you enroll, consider these additional protections:
- Place a fraud alert or security freeze with the three major credit bureaus.
- Review bank and credit-card statements for unfamiliar transactions.
- Change passwords for online banking, email, and tax-filing platforms.
- File your 2025 tax return as early as possible to prevent refund fraud.
- Watch for phishing emails purporting to be from LMG or government agencies.
Can You File a Lawsuit?
If your Social Security number or financial data were exposed, you could be entitled to monetary damages and enhanced credit protection. Potential legal claims include negligence, breach of contract, and violations of consumer-protection statutes. Class actions are often filed in cases like this to consolidate the claims of everyone affected.
How to Preserve Your Rights
- Keep your notification letter. It is proof that your data was involved.
- Monitor your credit. Save evidence of any fraud or out-of-pocket expenses.
- Consult a data-breach attorney promptly. Statutes of limitation can be as short as one year for certain claims.
Timeline of Key Events
- 11/21/2024 – Unauthorized network access allegedly begins.
- 12/02/2024 – LMG detects unusual email activity.
- 08/07/2025 – Investigation into compromised data concludes.
- 08/13/2025 – Notification letters mailed to victims.
- 08/14/2025 – Breach reported to Maine Attorney General.
Frequently Asked Questions
What did Leonard, Mulherin & Greene say in its breach notice?
The firm stated that an unauthorized party accessed its network and may have obtained files containing names, Social Security numbers, and financial account data. LMG is offering one year of complimentary credit monitoring.
How many people were affected by the Leonard, Mulherin & Greene data breach?
LMG’s filing with the Maine Attorney General lists roughly 3,300 individuals.
Is free credit monitoring enough after the LMG breach?
Credit monitoring helps detect fraud but does not prevent identity theft. Victims should also consider placing a security freeze and exploring legal options for compensation.
Can I join a class-action lawsuit against Leonard, Mulherin & Greene?
Possibly. Data-breach class actions are often filed when Social Security numbers or financial data are exposed. Consult an attorney to confirm eligibility.
What deadlines apply to an LMG data breach claim?
Deadlines vary by state and claim type, but some privacy statutes require action within one year. Contact counsel promptly to preserve your rights.