In this subtitle the following words have the meanings indicated. “Proper invoice” means an invoice that: contains the contractor’s federal employer’s identification number or Social Security number; contains the contract or purchase order number or other description of the contract; and contains or is accompanied by the substantiating information and documentation required by regulation or contract. “Receipt date” means the date that a proper invoice is received by the Commission.

It is the policy of the Commission that the Commission shall make a payment in accordance with any authorized, written procurement contract to the contractor within 30 calendar days after the receipt date of a proper invoice.

Any amount due and payable under law and an authorized, written procurement contract that remains unpaid for more than 45 calendar days after the receipt date shall accrue interest, at the rate specified in § 11–107(a) of the Courts Article, for the period that begins 31 calendar days after the receipt date.

The Commission is not liable for the payment of interest under this subtitle: if a proper invoice for accrued interest is not submitted within 30 calendar days after the date of the Commission’s check for payment of the amount on which the interest accrued; for more than 1 year following the 31st calendar day after the receipt date; on amounts representing unpaid interest; or if there is a dispute, as determined by the Commission, as to any material factor in the contract or purchase order.