Masimo Confirms Cyberattack as Audio Business Divested to Samsung
Masimo Corporation, a global medical technology firm, confirmed a significant cybersecurity breach that disrupted core operations across its network. The disclosure was made through a Securities and Exchange Commission (SEC) filing submitted alongside its quarterly earnings report on May 6, 2025.
The incident comes as Masimo also announced the sale of its consumer audio division, Sound United, to Harman International, a subsidiary of Samsung Electronics, for $350 million.
Network Breach Detected on April 27
Masimo stated that it detected unauthorized activity on its on-premise systems on April 27, 2025. The incident has impacted operations at “certain manufacturing facilities,” which have since been running below normal capacity.
Customer order processing, fulfillment, and shipping have also experienced delays.
“Upon detection, we activated our incident response protocols and implemented containment measures, including proactively isolating impacted systems,”
— SEC Filing, Masimo Corporation
Masimo’s official website has been offline for several days, and attempts to contact the company directly have gone unanswered, according to tech outlet Strata-gee.
Ongoing Investigation and Limited Scope
The company said it is working with third-party cybersecurity experts and coordinating with law enforcement to investigate the incident and minimize further impact.
At this stage, Masimo has not attributed the cyberattack to any known threat group, and no ransomware gang listed in Cybernews’ Ransomlooker tool has claimed responsibility.
“The Company has been working diligently to bring the affected portions of its network back online, restore normal business operations, and mitigate the impact of the incident.”
— Masimo Corporation
The company added that the attack “appears unrelated to and is not affecting the Company’s cloud-based systems.”
It remains unknown whether product users or customer data have been affected. Masimo has yet to provide further details in response to media inquiries.
Sound United Brands Sold to Samsung
On the same day the cyberattack disclosure was made, Masimo announced the sale of its Sound United audio division. The transaction includes iconic brands such as:
- Bowers & Wilkins
- Denon
- Marantz
- Polk Audio
- Definitive Technology
- Classé Audio
- Boston Acoustics
The buyer, Harman International, will take over all relevant Sound United subsidiaries under the deal.
Masimo, best known for medical innovations in pulse oximetry, brain function monitoring, and wearable sensors, holds a market valuation of nearly $9 billion. The sale signals a strategic shift toward its core healthcare technologies amid operational challenges stemming from the Masimo cyberattack.
