Which situation describes Medicare Secondary Payer (MSP)?

Medicare Secondary Payer (MSP) refers to a situation where another insurer is primarily responsible for paying a beneficiary's medical expenses before Medicare steps in to cover the remaining costs. This typically occurs when an individual has coverage through an employer, a spouse's employer, or another health plan that is liable for payment. In such cases, Medicare acts as a secondary payer, meaning it processes claims only after the primary insurer has made their payment or determination.

This concept is crucial in understanding how Medicare interacts with other insurance plans, as it helps to avoid duplicate payments and ensures that the primary insurer pays its share before Medicare takes on additional costs. Being aware of MSP is important for beneficiaries and healthcare providers alike to navigate billing processes correctly and ensure appropriate payment sources are utilized. The other choices do not accurately reflect this term, focusing on circumstances where Medicare is either the sole payer or claims are denied, which do not fit the definition of MSP.