"According to section 216 of HR 4302, starting in 2017 CMS will pay labs according to the weighted median of rates from private payors for tests. Labs will have to begin reporting rates from payors to CMS in 2016."
Plus special treatment for multiplex assays:
"Although the market-based pricing provisions apply to all clinical labs, HR 4302 sets up a new category of advanced diagnostic laboratory tests – defined as a test that gauges multiple markers based on an algorithm or a test approved or cleared by the FDA. An advanced diagnostic must be a single-source test; that is, it has to be sold by the lab that developed it. CMS will update pricing annually for advanced tests. For all other diagnostics, pricing will be updated every three years."