The Department of Labor finalized a PBM disclosure rule requiring pharmacy benefit managers to provide detailed compensation information to self-insured employer clients. Regulators estimate the rule could lower drug costs for employers and workers by $22 billion over a decade. Under the final rule, PBMs will disclose payments they receive from drugmakers, pharmacies and other supply-chain entities, including rebates and “spread” payments—amounts kept when the plan reimburses above what the PBM pays pharmacies. Disclosures will be required when negotiating or renewing contracts and again every six months, with employers allowed to audit disclosures once per year. The rule takes effect in July 2027 and includes penalties and potential contract invalidation for noncompliance. The final text faces strong opposition from PBMs, even as employers and policymakers backed the change. The move intensifies the compliance and operational burden on PBMs while accelerating scrutiny of rebate structures and administrative fees that have contributed to affordability concerns.