Sermo Data Breach Lawsuit Investigation

Shamis & Gentile P.A., one of the nation's premier class action law firms specializing in data breach cases, is investigating the WorldOne Inc. dba Sermo data breach.

If you were affected by the data breach, your sensitive personally identifiable information may have been exposed, and you may be eligible for compensation.

About Sermo

Sermo is a global market research and online community platform for healthcare professionals, especially physicians. Founded in 2000 and headquatered in New York, Sermo offers a space to collaborate, discuss clinical cases and share medical insights.

The company employs more than 500 people and has expanded its reach through mergers and acquisitions, including a merger with WorldOne in 2012.

What Happened?

On April 10, 2024, Sermo discovered suspicious activity within its network environment following a power outage at its data center in Denmark.

It was later determined that this outage was caused by a ransomware attack, with the group Black Basta claiming responsibility. The unauthorized access and acquisition of information occurred between March 19, 2024, and April 10, 2024.

After the incident, Sermo’s parent company was identified on the attacker’s leak site, and some data was posted online. The company spent months downloading and reviewing the leaked data to determine what information was exposed. By September 20, 2024, Sermo had fully downloaded the dataset and confirmed that sensitive personal information was involved.

Additionally, the MEDUSA ransomware group also claimed responsibility for a related attack, stating on July 1, 2025, that they had obtained organization data and intended to publish it on the Tor network within 10 to 11 days.

The breach was disclosed to the Maine Attorney General. The company also notified consumers in writing on Feb. 9, 2026.

A total of 2,674 people in the United States were affected, including five residents in Maine.

Information Exposed:

• Social Security numbers
• First and last names

You May Be Entitled to Compensation

If you were notified that your information was involved in the Sermo data breach, you may be eligible to participate in a class action lawsuit and receive compensation. Lawyers are actively investigating claims and can help guide you through the process.

To take the next step, complete the below form to see if you qualify to join the lawsuit.

Sources

• Maine Attorney General
• Dark web