A federal court ruled this month that a Montana insurer is entitled to federal compensation for subsidy payments under the Affordable Care Act (ACA) that President Trump abruptly ended last October, a ruling that could reverberate through insurance markets and cost the government hundreds of millions of dollars. At issue are payments for so-called cost-sharing reductions, discounts that enhance the value of health insurance policies purchased from the ACA’s marketplaces by reducing deductibles, co-payments and other out-of-pocket costs for low-income consumers. Judge Elaine D. Kaplan of the United States Court of Federal Claims said this month that Mr. Trump’s actions violated a government promise to insurance companies participating in the health law. (Robert Pear, New York Times)