On December 14, 2021, the Centers for Medicare and Medicaid Services (CMS) unexpectedly issued a letter to U.S. Senator Ron Widen (D-OR) indicating that CMS plans to use its “administrative authority to issue proposed rulemaking” addressing price concessions and direct and indirect remuneration (DIR) fees that pharmacy benefit managers (PBMs) have increasingly charged to specialty and retail pharmacy providers in Medicare and other pharmacy benefit programs in recent years. The proposed regulation was issued on January 12.