Medical providers shall collect to the extent possible from third-party payers such as Medical Assistance, Medicare, and private insurers. Facilities shall direct medical providers to invoice the facility for the cost of those services not covered by third-party payers. For Medical Assistance recipients, the Secretary or the Secretary's designee shall determine which services are specifically provided for in the facility's budget and are included in the facility's Medical Assistance per diem rate, and, therefore, may not be billed directly to the Maryland Medical Assistance Program. The purchase of care agreement entered into with the provider shall state that “The provider, in accepting this client for care, agrees to pursue recovery of the cost of care from all third-party payers and any state, federal, and federal-state program for which this client might be eligible, based on the information furnished by the facility before invoicing (name of facility).” Payment in Full. If a third-party source of payment is intended to be payment in full, the facility may accept but may not pay invoices for the service rendered, unless payment by the third-party source is denied. If a third-party source of payment is not intended to be payment in full, the facility shall pay the amount of the bill not paid by the third-party payer. Medical providers shall submit all invoices to the appropriate facility within 12 months of the date of services.