If a new federal rule withstands politics and potential court challenges, U.S. health care prices may finally be freed from their historic black box. The Centers for Medicare & Medicaid Services, along with the Departments of Labor and the Treasury, issued the Transparency in Coverage final rule Oct. 29 requiring most private health plans to disclose pricing and cost-sharing information so Americans will know in advance how much they will have to pay for prescription drugs, medical devices and other health care products and services.