Pharmacy Benefit Manager Transparency Act of 2023 This bill generally prohibits pharmacy benefit managers (PBMs) from engaging in certain practices when managing the prescription drug benefits under a health insurance plan, including charging the plan a different amount than the PBM reimburses the pharmacy. The bill also prohibits PBMs from arbitrarily, unfairly, or deceptively (1) clawing back reimbursement payments, or (2) increasing fees or lowering reimbursements to pharmacies to offset changes to federally funded health plans. PBMs are not subject to these prohibitions if they (1) pass along 100% of any price concession or discount to the health plan, and (2) disclose specified costs, prices, reimbursements, fees, markups, discounts, and aggregate payments received with respect to their PBM services. Further, PBMs must report annually to the Federal Trade Commission (FTC) certain information about payments received from health plans and fees charged to pharmacies. The FTC and state attorneys general are authorized to enforce the provisions of the bill.