Configure the split-billing or TPA platform to identify Medicaid fee-for-service (FFS) payer claims at the point of adjudication using BIN/PCN values associated with your state's Medicaid FFS program; maintain a current BIN/PCN lookup table for your state
Apply carve-out logic: when a prescription is identified as billing to Medicaid FFS, route the drug purchase to non-340B inventory (WAC or GPO account) so no 340B discount is applied; tag the claim record as Medicaid FFS carved-out
Download the HRSA 340B Medicaid Exclusion File from the OPAIS system (available at 340bregistration.hrsa.gov); this file lists the covered entity's registered contract pharmacies and is used by state Medicaid programs to identify potential duplicate discount claims
For Medicaid managed care (MMC) patients, determine whether your state has a carve-in or carve-out policy for 340B under MMC; carve-in states require the covered entity to use 340B purchasing for MMC patients, while carve-out states treat MMC claims like FFS for duplicate discount purposes
Audit carve-out accuracy quarterly: reconcile Medicaid FFS dispense records against 340B purchases to confirm no 340B-purchased drugs were billed to Medicaid FFS; document findings for HRSA compliance purposes
Report any identified duplicate discounts to HRSA and the applicable state Medicaid agency promptly; self-disclosure typically results in less severe corrective action than audit-identified violations
Known gotchas
Medicaid managed care carve-in/carve-out policy varies by state and can change with state plan amendments; covered entities must monitor state Medicaid policy changes and update their split-billing logic accordingly
A single prescription can create a duplicate discount if the drug was 340B-purchased AND the PBM submits a manufacturer rebate request for the same claim; the TPA's carve-out logic must flag all potential rebate-eligible payer types, not just Medicaid FFS
The Medicaid Exclusion File in OPAIS reflects registered facilities and contract pharmacies; if a new contract pharmacy is not yet reflected in the file, there is a window of time during which duplicate discount risk exists even with correct carve-out logic
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp