STAT+: DOJ probes device maker whose test resulted in lucrative diagnoses for UnitedHealth and other insurers
The Department of Justice is investigating Semler Scientific for possible violations of an anti-fraud law related to its marketing of an artery disease test

The Department of Justice is investigating Semler Scientific for possible violations of a federal anti-fraud law related to its marketing of a product known as QuantaFlo, a test used in the diagnosis of peripheral artery disease by UnitedHealth Group and other large insurers.
In a recent filing with the Securities and Exchange Commission, Semler disclosed that the government is investigating the use of QuantaFlo related to claims made for reimbursement from government health programs, which in some cases pay insurers more money to cover patients diagnosed with peripheral artery disease.
The SEC filing states that on Feb. 11, Semler began — but then cut off — settlement discussions with the Department of Justice related to possible violations of the False Claims Act, an anti-fraud law designed to prevent companies from collecting unwarranted payments from the federal government. The company indicated that the investigation began in 2017 and picked up in intensity in late 2024 and early 2025.