The Supreme Court said it will hear oral arguments on March 4 in a lawsuit over whether the Obama administration is improperly providing tax credits to consumers who purchase health insurance through the federal exchanges.The case will determine the fate of the tax credits to millions of consumers who have obtained insurance coverage through HealthCare.gov, the federal marketplace. The Supreme Court decided Nov. 7 to hear the lawsuit from Virginia, King v. Burwell, that challenges a key part of the Affordable Care Act. In all, an estimated 4.7 million people receive billions of dollars in subsidies to buy health coverage on the federal exchange.Challengers claim the language in the health law only permits people who buy insurance from state-run exchanges to obtain the tax credits. Supporters of the law say it was always intended to provide the subsidies to people who bought coverage on the federal exchanges, too. HealthCare.gov, the federal exchange, now serves 37 states.On March 4, the Supreme Court will only hear arguments related to the King case.…The tax credits are considered central to the law’s success. Under the ACA, most Americans must have health insurance or pay a penalty. The exchanges let individuals who don’t have insurance from their employer, Medicaid or Medicare to purchase insurance policies, with tax credits for lower-income consumers.