When UnitedHealth, the nation’s largest health insurer, announced earlier this month that it would exit the Affordable Care Act exchange business in all but three states, the obvious question was, who’s next? After all, if the nation’s biggest health carrier can’t make the Obamacare exchanges profitable, who can? UnitedHealth announced it expects to lose $650 million on its ACA business in 2016, although its first-quarter earnings beat analyst expectations, thanks to the company’s highly profitable consulting and technology businesses.

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