For purposes of this subpart—
Appropriate MAC means a MAC that has a contract under section 1874A of the Act to perform a particular Medicare administrative function in relation to:
(1)
A particular individual entitled to benefits under Part A or enrolled under Part B, or both;
(2)
A specific provider of services or supplier; or
(3)
A class of providers of services or suppliers.
Medicare Administrative Contractor (MAC) means an agency, organization, or other person with a contract under section 1874A of the Act.