Question: Who is responsible for identifying and correcting overpayment in any Centers for Medicare & Medicaid Services (CMS) reimbursement? Is there a lookback period or is any claim ever paid fair game? AAPC Forum Participant Answer: According to CMS and the Medicare Learning Network (MLN), overpayments may be identified by CMS; a Medicare Administrative Contractor (MAC); or a provider, via self-identification. CMS leans on providers to be keeping track of payments.“Through reasonable diligence, a provider can identify any overpayment and calculate the amount,” CMS warns in an MLN fact sheet. Section 1128J(d) of the Social Security Act requires providers to report and return any self-identified overpayment to its respective MAC within 60 days of identifying the overpayment, six years since the overpayment (six years constitutes the “lookback period”), or a corresponding cost report due date. Overpayments of $25 or more will spur a MAC to send a demand letter requiring repayment. Heads up: One Part B MAC recently reminded providers about the intersection between invoice price and subsequent payments after that fact that may lead to an overpayment — and recoupment. “Total invoice price is the net amount of provider pays for an item in service, considering ALL discounts, rebates, refunds, or other adjustments,” reminded CGS Medicare in a May 1 release. “In the circumstances that the total invoice amount is paid, and the provider subsequently receives payment from a third party, such as a volume-based discount, rebate, refund, or other adjustments this is considered ‘overpayment.’ The provider is obligated to report and voluntarily refund the overpaid amount.” For more information about Medicare overpayments, review the fact sheet at www.cms.gov/outreach-and-education/ medicare-learning-network-mln/mlnproducts/ downloads/ overpaymentbrochure508-09.pdf.