Quest Diagnostics Says Patient Records Were Reached Through Its Lab Ordering System
Quest Diagnostics told the Securities and Exchange Commission that an unauthorized party reached certain patient records through Quanum LSM, a system that some of its clients use to place test orders and look up results. The clinical laboratory company says it learned of the unauthorized access Oct. 21, 2026, and disclosed it in a Form 8-K the next day.
According to the filing, Quest presents the finding on patient records as what it believes at this time, and says the full scope of the unauthorized access remains under investigation.
The filing goes no further on scope. It gives no count of affected records, no list of the categories of data involved, and no date range for the access. It does not say how the access was obtained, names no party, and does not say whether or when affected people will be notified.
Quest says it started its cybersecurity incident response procedures to contain the activity, assess and investigate the nature and scope of the incident, and put remedial measures in place. It says it has notified federal law enforcement authorities and engaged outside cybersecurity experts to help with the investigation and the response.
The company's own assessment of the effect is that the incident has not materially disrupted its business operations or its ability to serve patients. The filing's cautionary section lists the impact of the incident among the risks that could make Quest's actual results differ from current management expectations.
The disclosure was made under Item 8.01, Other Events, and signed by Sean D. Mersten, Quest's vice president and corporate secretary, Oct. 22, 2026.
