NovoCure Limited (NASDAQ: NVCR) disclosed that an unauthorized party gained access to some of its information systems in mid-August 2026, exposing data from more than 1,400 U.S. patient records and a smaller set of additional patient files.

According to the company's filing, the exposed data included internal patient ID numbers for over 1,400 U.S. patients, though no patient names or other identifying information were included for that group. Fewer than 50 patients in the western United States had additional identifying information exposed. The breach also included general contact information for healthcare providers and NovoCure employees, such as job titles and phone numbers.

The company said no access to its medical treatment devices was obtained and that its operations and systems remain fully functional. Upon detecting the breach, NovoCure activated its cybersecurity response plan, implemented containment measures, and engaged independent cybersecurity forensic experts to assist with the investigation.

NovoCure said it is continuing to evaluate applicable regulatory and legal notification requirements and will notify impacted patients as required. The company stated it does not currently believe the incident will have a material impact on its financial condition or results of operations, but noted it is still gathering information. If that assessment changes, the company said it would file an amendment to its Form 8-K within four business days of making such a determination.