42 CFR § 455.436 - Federal database checks.
The State Medicaid agency must do all of the following:
(a) Confirm the identity and determine the exclusion status of providers and any person with an ownership or control interest or who is an agent or managing employee of the provider through routine checks of Federal databases.
(b) Check the Social Security Administration's Death Master File, the National Plan and Provider Enumeration System (NPPES), the List of Excluded Individuals/Entities (LEIE), the Excluded Parties List System (EPLS), and any such other databases as the Secretary may prescribe.
(1) Consult appropriate databases to confirm identity upon enrollment and reenrollment; and
(2) Check the LEIE and EPLS no less frequently than monthly.