Medical testing firm and clinical laboratory Quest Diagnostics has revealed that a data breach has led to the records of nearly 12 million of its customers being exposed. The data includes financial data, Social Security numbers and medical information.
Quest Diagnostics was itself not the target of hackers, but the American Medical Collection Agency (AMCA) was. The company is used by Optum360 for billing collections services, and Optum360 is used by Quest Diagnostics.
The laboratory says that it was notified by AMCA on May 14 about potential unauthorized activity on AMCA’s web payment page. Two weeks later Quest and Optum360 were told that the personal information of 11.9 million Quest Diagnostic customers were included.