Cigna and Humana have resumed informal merger discussions, although they are still in the early stages. Cigna is prioritizing the sale of its Medicare Advantage business before pursuing any further deals.

The news of the discussions caused an increase in Humana's stock and a decrease in Cigna's shares. The potential merger could create a strong competitor to UnitedHealth Group and CVS Health. However, the Federal Trade Commission is closely monitoring healthcare merger activities and has recently increased reporting requirements.

Cigna is currently being scrutinized by the FTC in relation to the pharmacy benefit management sector, and both companies have faced federal opposition in previous merger attempts.