Quest Diagnostics Investigates Unauthorized Access to Lab Platform
Quest Diagnostics is investigating a cybersecurity incident involving its Quanum Lab Services Manager platform, which some healthcare providers use to order laboratory tests and view results. The company said it discovered unauthorized access on Wednesday and disabled access to the platform. It expects to restore full functionality as soon as Friday.
Quest said patient health information or personally information was involved. It believes some patient data was accessed, but has not determined what information was obtained or how many people may be affected. The company said it has stopped the unauthorized access.
As a precaution, Quest also temporarily paused access to its Essential Insights and LabHQ systems. It said there was no indication that data on those systems was accessed. The company reported that its core operations remain unaffected and that its ability to serve patients has not been materially disrupted.
Healthcare providers who normally use Quanum Lab Services Manager can place orders using paper forms or Quest’s Quanum eLabs platform. Other electronic ordering systems remain available. Quest said it does not expect testing delays for clients who do not use the affected platform.
In a Thursday filing with the Securities and Exchange Commission, Quest said it had notified federal law enforcement and brought in outside cybersecurity specialists to assist with its response. It is working to identify affected patients and providers and said it will send notices as required by law.
The incident recalls a separate breach disclosed in 2019 involving American Medical Collection Agency, a third-party billing provider. That company reported unauthorized access to a system containing information associated with approximately 11.9 million Quest patients. Quest said its own information technology systems were not involved in that case.
Quest reported approximately $11 billion in revenue in 2025. It has not disclosed whether the current incident will have financial consequences. The scope of the data exposure remains under investigation, and the company has not provided a timetable for completing its review.