Understanding your MJMS Family Office Services LLC and Madden, Jiganti, Moore & Sheridan LLP data breach notification letter
If a MJMS Family Office Services LLC and Madden, Jiganti, Moore & Sheridan LLP letter arrived in your mailbox, here is what it means, why you received it, and the free steps you can take right now.
Why you received this letter
MJMS Family Office Services LLC and Madden, Jiganti, Moore & Sheridan LLP operate at the intersection of boutique legal counsel, wealth management, and private client fiduciary services. These entities handle ultra-high-net-worth individuals, family offices, trusts, and closely held businesses, requiring them to centralize an extraordinary volume of confidential personal and financial dossiers. Because of the nature of their practice, they routinely collect, process, and store highly sensitive information, including comprehensive estate planning documents, tax returns, corporate governance records, wire instruction histories, and private identification numbers. This creates an inviting repository for cybercriminals seeking to exploit high-value targets. In 2026, the organizations reported a significant data security incident to the Massachusetts Attorney General, signaling a breach of the digital safeguards protecting their network infrastructure. While the precise mechanics of the intrusion continue to be evaluated, incidents affecting specialized legal and financial practices frequently involve sophisticated threat actors executing targeted credential harvesting, unauthorized network penetration, or ransomware deployments. These attacks often exploit vulnerabilities in legacy client portals, third-party vendor integrations, or inadequately secured cloud storage environments where dense legal and financial documents reside. The exposure resulting from this incident encompasses a dangerous aggregation of personally identifiable information and financial data. Victims face the compromise of core identifiers such as full names, dates of birth, and Social Security numbers, alongside deeply sensitive financial account numbers, trust agreements, and tax documentation. In the context of family office and legal services, the exposure of tax return information and banking details provides bad actors with the precise instruments needed to execute sophisticated tax fraud, synthetic identity creation, and unauthorized wire transfers or financial account takeovers. Under state and federal data protection standards, including Massachusetts general laws governing consumer privacy and data security, entities entrusted with sensitive private client data have a stringent legal duty to implement and maintain robust administrative, physical, and technical safeguards. Law firms and family offices are bound by strict ethical and statutory obligations to protect client confidences. A breach of this magnitude strongly suggests potential failures in encryption protocols, multi-factor authentication enforcement, or timely vulnerability patching, representing a departure from the reasonable security standards required to repel modern cyber threats. Receiving a data breach notification letter from MJMS Family Office Services LLC and Madden, Jiganti, Moore & Sheridan LLP serves as formal acknowledgment that your private information was compromised due to inadequate security measures. Legally, this notification establishes the necessary standing to participate in a class action lawsuit aimed at holding the entities accountable for failing to safeguard your data. Under the law, you do not need to prove that you have already suffered actual financial loss or identity theft to seek legal redress. Our firm handles these complex privacy cases on a contingency fee basis, meaning you pay absolutely nothing out of pocket, and there are no fees unless we successfully recover compensation on your behalf.
What to do after the letter
Confirm the notice is genuine
A legitimate MJMS Family Office Services LLC and Madden, Jiganti, Moore & Sheridan LLP notice references the specific incident reported to the Massachusetts Attorney General and describes which categories of your information were involved. Compare the letter against the public filing before acting on any links or phone numbers it contains.
Keep the letter — it is your proof of connection
The notification letter is the document that ties your personal information to this incident. Keep the original and photograph it. If you later request a case review, this letter is the strongest evidence that you were among the affected individuals.
Protect your accounts and credit
Depending on what was exposed, consider a free credit freeze with all three bureaus, new passwords for reused credentials, and monitoring of financial statements. These steps are free and do not require you to wait for anyone's permission.
Find out whether you have a claim
Whether the MJMS Family Office Services LLC and Madden, Jiganti, Moore & Sheridan LLP breach gives you a legal claim depends on the facts. A free, no-obligation case review will tell you where you stand — there is no cost and no commitment to find out.
This page summarizes a data breach reported to the Massachusetts Attorney General for informational purposes and is attorney advertising. It does not create an attorney-client relationship. DataBreachLegalCenter.com does not provide legal advice through this page.