Exact Sciences is suing the national insurer Humana for its refusal to pay for the company’s non-invasive colon cancer test.

The lawsuit, filed in a federal court in Kentucky this week, argues Humana has illegally refused to pay more than $800,000 worth of claims for the Cologuard test. The test analyzes stool samples for abnormal cells that signal colon cancer. Read the full WisBusiness story here.