Masimo 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 Masimo 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 Masimo

Masimo is a global medical technology company headquartered in Irvine, California. Founded in 1989, the company has grown to employ thousands of people worldwide and is publicly traded on NASDAQ under the symbol MASI.

Masimo is known for developing non-invasive patient monitoring technologies, medical devices, and a wide range of sensors used in healthcare settings.

The company’s products include patient monitors, pulse oximeters, specialty sensors, and central monitoring systems. Masimo’s technology is used in hospitals around the world and is licensed by other major medical device manufacturers.

What Happened?

In late April 2025, Masimo discovered unauthorized activity on its on-premise network. The company immediately activated its incident response protocols and began working with third-party cybersecurity professionals to investigate and contain the breach. Law enforcement was also notified.

According to a posting on the dark web by a threat actor known as "almighty4444," data allegedly stolen from Masimo was leaked online. The breach reportedly included 61 MB of information containing user data and their orders. The incident impacted Masimo’s ability to process, fulfill, and ship customer orders, causing temporary disruptions to its manufacturing operations.

The investigation is ongoing, and the full scope of the breach is still being determined.

Your Rights and Next Steps

If you are a current or former customer of Masimo, or if you have interacted with the company in a way that required providing personal information, your data may have been compromised in this breach. It is important to remain vigilant for signs of identity theft or fraudulent activity.

Here are some steps you can take:

1. Monitor your financial accounts and credit reports for any unusual activity.
2. Consider placing a fraud alert or credit freeze with the major credit bureaus.
3. Save any correspondence you receive from Masimo regarding the breach.
4. Document any suspicious activity that may be related to this incident.

Lawyers are ready to help you understand your rights and explore your legal options. If your information was exposed, you may have grounds to join a class action lawsuit seeking compensation for damages related to the breach.

You May Be Entitled to Compensation

If you were affected by the Masimo data breach, you could be eligible for financial compensation. Lawyers are actively investigating this incident and are prepared to help you pursue your rights.

To find out if you qualify and to take the next step in protecting yourself, complete the below form to join the lawsuit.

Sources

• Masimo Notice of Data Breach
• Dark Web