Yet the question remains whether regulators will embrace the deals as quickly as these rivals have embraced one another. Four of the largest U.S. insurers will combine to form two health-care powerhouses, and the competition may spur more mergers among smaller players.
"The effect is going to be very specific to markets," said Christopher Koller, the president of the Milbank Memorial Fund, a health policy research foundation that advises states.
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"What the [Federal Trade Commission] will want to determine is, does an insurer have a big enough market share in a particular market so as to eliminate or reduce competition," asked Koller, who served as Rhode Island's health insurance commissioner from 2006-2013.
Still, Koller argues that when it comes to insurance the bar has been set fairly high by federal regulators.
"I regulated a market where a domestic, local, non-profit (Blue Cross plan) had 60-70 percent of market share. And I certainly didn't have the FTC marching in there trying to take it apart," he said.
Yet current Rhode Island Health Insurance Commissioner Kathleen Hittner said these new large insurer deals should be carefully scrutinized because it could hurt the burgeoning consumer market.
"People want consolidation for efficiency, which is what (insurers) promote," said Hittner. "If you have competition, they look at the other plans and they try to have similar plans," she said.
"I think if you take away that competition, we will see higher rates and we will see less ability for the states to adjust those rates," she added.