Group health plans and liability, no-fault and worker’s compensation insurers should confirm they are properly coordinating benefits with Medicare Advantage organizations (MAOs) to avoid a private cause of action for double damages to recover amounts under the Medicare Secondary Payer Act (MSP Act) in light of the U.S. Supreme Court’s denial of certiorari on an appeal of the Third Circuit’s decision in In Re Avandia Marketing Sales Practices GlaxoSmithKline LLC v. Human Medical Plans, Inc.  (Glaxo).  The Supreme Court’s decision denying certiorari reported here lets stand a Third Circuit decision that the private right of action provision in the MSP Act, set forth at 42 U.S.C. 1395y(b)(3), gives Humana a private cause of action as a primary plan against GSK to recover the double damage award.