; and (2) any such other remuneration is a flat fee-based service fee that a manufacturer of prescription drugs pays to a pharmacy benefit manager for services rendered to the manufacturer that relate to arrangements by the pharmacy benefit manager to provide pharmacy benefit management services to a health plan or health insurance issuer, if certain conditions established by the Secretary are met, including requirements that the fees are transparent to the health plan or health insurance issuer. . (b) Effective date Section 2729A of the Public Health Service Act, as added by subsection (a), shall take effect on January 1, 2021. 366. PBM transparency and elimination of DIR fees (a) Prohibiting medicare PDP sponsors and MA–PD organizations from retroactively reducing payment on clean claims submitted by pharmacies (1) In general Section 1860D–12(b)(4)(A) of the Social Security Act ( 42 U.S.C. 1395w–112(b)(4)(A) ) is amended by adding at the end the following new clause: (iv) Prohibiting retroactive reductions in payments on clean claims Each contract entered into with a PDP sponsor under this part with respect to a prescription drug plan offered by such sponsor shall provide that after the date of receipt of a clean claim submitted by a pharmacy, the PDP sponsor (or an agent of the PDP sponsor) may not retroactively reduce payment on such claim directly or indirectly through aggregated effective rate or otherwise except in the case such claim is found to not be a clean claim (such as in the case of a claim lacking required substantiating documentation) during the course of a routine audit as permitted pursuant to written agreement between the PDP sponsor (or such an agent) and such pharmacy. The previous sentence shall not prohibit any retroactive increase in payment to a pharmacy pursuant to a written agreement between a PDP sponsor (or an agent of such sponsor) and such pharmacy. . (2) Effective date The amendment made by subsection (a) shall apply with respect to contracts entered into on or after January 1,