Digital cardiac-monitoring company iRhythm Holdings disclosed a data breach in a June 10, 2026 SEC filing after attackers contacted the company on June 9 demanding ransom to avoid publishing stolen health information.
What iRhythm confirmed
The company said it confirmed data exfiltration from third-party-hosted business applications accessed via social engineering. Categories include patient protected health information and personal data; iRhythm stated payment cards, clinical device systems, manufacturing, and financial reporting were not affected.
Scale and timeline
iRhythm classified the incident as material because of the volume of potentially affected data but had not published a public victim count when BleepingComputer reported the disclosure on June 16, 2026. The firm serves more than 12 million patients through its Zio cardiac monitoring platform.
What patients should do
- Watch for official iRhythm breach notifications—not ransomware leak downloads.
- Enable MFA on email accounts used for healthcare portals.
- Report suspicious medical-billing or identity messages to your provider and insurer.
Canonical record: iRhythm 2026 on BreachHistory.
Sources: BleepingComputer, SEC filing