We recently prepared an executive summary of a proposed rule issued on December 1, 2014 by the Centers for Medicare and Medicaid Services (“CMS”), at the request of the American Health Lawyers Association.  If adopted, the rule would modify the regulatory requirements for Accountable Care Organizations (“ACOs”) that participate in the Medicare Shared Savings Program (“MSSP”) ( 42 CFR Part 425).  In the proposed rule, CMS addresses a broad array of issues including data sharing, beneficiary attribution and performance based risk tracks for ACOs.  While some of the changes proposed by CMS are merely technical, there are several changes which could have a significant impact on ACOs and their constituent healthcare providers. Some of the more significant changes include: (1) more stringent eligibility requirements for ACO participants, including restrictions on governing bodies and the creation of separate legal entities; (2) modified risk tracks for ACO participants and the creation of a 3rd track involving prospective assignment of beneficiaries; and (3) a broader beneficiary assignment methodology for attribution to ACOs.  To learn more, please click here to read the full executive summary prepared by Sheppard Mullin and AHLA on the proposed rule.