In a statement, the company said: "Humana anticipates proposing a number of changes to retain a viable product for individual consumers, where feasible, and address persistent risk selection challenges. Such changes may include certain statewide market and product exits both on and off exchange, service area reductions and pricing commensurate with anticipated levels of risk by state."

Humana, UnitedHealth, and others have complained that the exchange system's insurance purchasing "loophole" that allows people to sign up outside traditional enrollment periods has led to thousands of plan purchases by people who were uninsured, but suddenly experienced health events. These patients are, of course, more costly to insure and have been a major contributor to losses on exchange business.

However, as reported in Forbes, the pullbacks by Humana and UnitedHealth will likely be offset by more aggressive exchange selling by such insurers as Anthem and Centene. Even Humana's merger partner, Aetna, has said it intends to stay the course with the exchanges — a position that may well be tested once the merger is complete.