On November 21, 2011, the Center for Consumer Information & Insurance Oversight (“CCIIO”), in the Centers for Medicare & Medicaid Services (“CMS”), announced its determination that a health insurance premium rate increase of 11.58 percent in the small group market in Pennsylvania represented an “unreasonable” rate increase, while an 11.10 percent increase in the individual market in Montana did not. These long-awaited determinations represent the first application of CMS’s rate review regulations under federal health reform. This Implementing Health and Insurance Reform alert discusses these first federal rate review determinations, and their implications for insurance carriers and future insurance premium rate reviews.