Why the Justice Department rejected the Aetna and Anthem deals

After more than a year of scrutiny, the U.S. Justice Department filed requests for preliminary injunctions to block the two health insurance deals led by Aetna and Anthem that would shrink the number of national carriers from five to three if allowed to proceed. For the past year, Aetna has pursued its $37 billion acquisition of Humana to bolster its Medicare Advantage business. Anthem’s $53 billion bid for Cigna Corp.