With UnitedHealth, Humana, and now Aetna exiting ACA markets, many states might be left with only one Obamacare insurer.

Aetna CEO Mark Bertolini said the Justice Department's challenge to the company's merger with Humana would have a negative financial impact on Aetna and would impair Aetnas ability to continue its support of plans sold under the ACA.

The California Public Employees Retirement System, the largest U.S. public pension fund, dimmed its outlook.

We asked industry experts about what brokers need to use state exchanges more. Here's what they said.