The United States has filed a complaint under the False Claims Act against Rick Nassenstein, a resident of Florida and formerly the president, chief financial officer, and co-owner of Illinois-based Cardiac Imaging Inc. (CII), a provider of mobile cardiac positron emission tomography (PET) scans. The complaint alleges Nassenstein knowingly played a central role in a scheme whereby CII paid doctors exorbitant, above-fair market value fees who referred patients to CII for cardiac PET scans in violation of the Physician Self-Referral Law, also known as the Stark Law. It prohibits healthcare providers from billing Medicare for certain designated health services referred by a physician with whom the provider has a financial relationship, including a compensation arrangement, that does not meet any statutory or regulatory exception. Congress enacted the Stark Law to protect Medicare patients from financial arrangements that can adversely impact physicians’ decision making and lead to unnecessary services. Claims knowingly submitted to Medicare in violation of the Stark Law also violate the federal False Claims Act (FCA).