Although most health industry observers expressed optimism about the prospects of two proposed health insurance megamergers for much of the past year, few optimists remain now that the U.S. Department of Justice is suing to block Aetna from acquiring Humana and Anthem from buying Cigna. 

For starters, Cigna is sending strong signals that it is not interested in pursuing the deal anymore. Bickering between its leaders and those of the would-be parent company, Anthem, has already been extensively reported on before the Justice Department's announcement last week.

"Given the nature of the concerns raised by the DOJ and the overall status of the regulatory process, which under the terms of the merger agreement was led by Anthem, Cigna is currently evaluating its options consistent with its obligations under the agreement," the company said in a statement.