The Centers for Medicare & Medicaid Services (CMS) has published a new regulation that defines “uninsured” for the purpose of calculating the limit for how much individual hospitals may receive in Medicaid disproportionate share hospital payments (Medicaid DSH).
Under federal law, Medicaid DSH payments to hospitals cannot exceed the uncompensated costs of the services those hospitals provide to Medicaid recipients and the uninsured.  In calculating hospital-specific limits, according to the new regulation,

… the calculation of uncompensated care for purposes of the hospital-specific DSH limit will include the cost of each service furnished to an individual by that hospital for which the individual had no health insurance or other source of third party coverage.

This regulation is important to Pennsylvania safety-net hospitals because they receive Medicaid DSH payments and serve more uninsured patients than the typical hospital.
Find the complete regulation here, in the Federal Register.