From the article:

UNDER SECTIONS 1128 and 1156 of the Social Security Act, the Office of Inspector General (OIG) has the authority to exclude individuals from participation in federal healthcare programs, including Medicare and Medicaid. The purpose of exclusion, according to the OIG, is to protect the integrity of the healthcare system as well as protect the public from individuals and entities engaging in fraud and abuse. Healthcare providers thinking of employing an individual excluded by the OIG should think twice before doing so because of the potentially significant consequences.