The combination of the insurance giants was found to be a threat to competition.
CEO disputes have led to speculation the deal could break up, regardless of how the court battle with regulators is decided.
Plans to repeal and replace Obamacare have invigorated shares of Aetna and Humana, Anthem and Cigna, and UnitedHealth. Here's how to trade them using charts.
Trump's Twitter presidency has led to major market moves before. This time, it's hitting the health insurance sector.