Clinical lab testing titan Quest Diagnostics acknowledged in a press release on Monday that an “unauthorized user” had gained access to personal information on around 11.9 million customers, including some financial and medical data.
Per NBC News, news of the breach comes via way of a Securities and Exchange Commission filing in which Quest wrote that American Medical Collection Agency (AMCA), which provides billing collection services to Quest contractor Optum 360, had notified it of the breach in mid-May. NBC wrote that Quest said AMCA’s web payments page had possibly been compromised from Aug. 1, 2018 to March 30, 2019.
In its statement, Quest wrote that compromised information could include “certain financial data,” Social Security numbers, and some medical material—but not the results of laboratory tests on patients. It also wrote the extent of the breach remained unclear:
AMCA believes this information includes personal information, including certain financial data, Social Security numbers, and medical information, but not laboratory test results.
AMCA has not yet provided Quest or Optum360 detailed or complete information about the AMCA data security incident, including which information of which individuals may have been affected. And Quest has not been able to verify the accuracy of the information received from AMCA.
Quest added that it had “suspended” sending collections requests to AMCA. According to the Wall Street Journal, a spokesperson for Optum360 parent company UnitedHealth said their Optum360 systems were unaffected by the breach.