(a) (1) Whenever a health care service plan, including a specialized health care service plan, determines that in reimbursing a claim for provider services an institutional or professional provider has been overpaid, and then notifies the provider in writing through a separate notice identifying the overpayment and the amount of the overpayment, the provider shall reimburse the health care service plan within 30 working days of receipt by the provider of the notice of overpayment unless the overpayment or portion thereof is contested by the provider in which case the health care service plan shall be notified, in writing, within 30 working days. The notice that an overpayment is being contested shall identify the portion of the overpayment that is contested and the specific reasons for contesting the overpayment.

(2) If the provider does not make reimbursement for an uncontested overpayment within 30 working days after receipt, interest shall accrue at the rate of 10 percent per annum beginning with the first calendar day after the 30-working-day period.

(3) A prorated cost-sharing payment, or any portion thereof, made to a pharmacist for the dispensing of a partial fill pursuant to Section 4052.10 of the Business and Professions Code shall not be considered to be an overpayment pursuant to this section.

(b) (1) This subdivision shall only apply to a health care service plan contract covering dental services or a specialized health care service plan contract covering dental services pursuant to this chapter.

(2) The health care service plan’s notice of overpayment shall inform the provider how to access the plan’s dispute resolution mechanism offered pursuant to subdivision (h) of Section 1367. The notice shall include the name and address to which the dispute should be submitted and a statement that Section 1371.1 of the Health and Safety Code requires a provider to reimburse the plan for an overpayment within 30 working days of receipt by the provider of the notice of overpayment unless the provider contests the overpayment within 30 working days. The notice shall also include information clearly identifying the claim, the name of the patient, the date of service, and a clear explanation of the basis upon which the plan or the plan’s capitated provider believes the amount paid on the claim was in excess of the amount due, including interest and penalties on the claim. The notice shall also include a statement that if the provider does not make reimbursement of an uncontested overpayment within 30 working days after receipt of the notice, interest shall accrue at a rate of 10 percent per annum.

(Amended by Stats. 2017, Ch. 615, Sec. 4. (AB 1048) Effective January 1, 2018.)