What changes may be made to the Medicaid Exclusion File (MEF) from one quarter to the next?

A covered entity site can remove its 340B ID from the MEF to reflect that it will carve out all state Medicaid for the quarter. A covered entity site can add its 340B ID to the MEF to reflect that it will carve in at least one state Medicaid for the quarter. A covered entity site that carves-in, may add or remove state(s) it will bill 340B drugs during the quarter. A covered entity site that carves-in, may add or remove the billing number(s) it will use to bill a specific state for 340B drugs during the quarter.