Shares of companies tied to embattled Affordable Care Act exchange markets rose modestly on the day that news broke of Sens. Lamar Alexander, R-Tenn., and Patty Murray, D-Wash., striking a deal to fund cost-sharing subsidies for insurers.

The senators have been in negotiations to come to a consensus on funding the subsidies, among other tools to stabilize markets that have seen insurers exit or wind down plan offerings.

The announcement came days after news that subsidy payments meant to help to lower ACA premiums would no longer be disbursed to insurers, following which the markets saw a sell-off of companies with high ACA exchange exposure. But shares largely rebounded, coupled with a bump from strong third-quarter earnings results by UnitedHealth Group Inc., Piper Jaffray equity analyst Sarah James said in an interview.

"The stocks all traded off when the executive order came out and when the news of the lack of funding for CSRs came out," James said. "But I look at the recovery today, and it looks like a very optimistic rebalancing, because this is just the first step in a many-step process."

UnitedHealth closed the day at $203.89, up 5.53%, on much higher-than-average volume.

Centene Corp. closed up 3.17% at $93.80. Molina Healthcare Inc. moved up 2.77% to $61.54. Anthem Inc. rose 1.90% to $187.26, Humana Inc. increased 1.37% to $240.43, and Aetna Inc. rose 2.95% to $155.90, all on higher-than-average volume.

Health technology firm athenahealth Inc. finished the day up 4.05%.