The proposed mergers of health insurance companies Aetna and Humana and Anthem and Cigna “are likely to substantially lessen competition in numerous health insurance markets in the U.S., to the detriment of consumers,” the American Antitrust Institute told the Department of Justice today. “[O]ur review of publicly available information strongly suggests that the extent of the competitive harm posed by the proposed mergers cannot be counterbalanced by any merger-specific, cognizable efficiencies, or be effectively remedied in a way that fully restores competition lost by the mergers,” the independent organization wrote. “In light of the foregoing, the AAI recommends that the DOJ ‘just say no’ to the two deals that would fundamentally restructure the nation’s health insurance markets and create further incentives for ‘reactive’ consolidation in the health care supply chain that are largely driven by the quest to gain bargaining power.” In September and August letters to DOJ and the Department of Health and Human Services, the AHA said Aetna’s proposed acquisition of Humana and Anthem’s proposed acquisition of Cigna “have the very real potential to reduce competition substantially, increase the cost of premiums, and diminish the insurers’ willingness to be innovative partners with providers and consumers in transforming health care.”