A U.S. federal judge on Wednesday blocked health insurer Anthem‘s proposed $54 billion merger with smaller rival Cigna, a deal that would have created the largest U.S. health insurer by
membership.

The decision comes after a U.S. judge blocked a similar deal between rivals Aetna and Humana on Jan. 23. Wednesday’s ruling marks another victory for anti-trust officials, who sued the companies in July last year to stop the deal, saying it would reduce competition and raise prices for consumers.

Cigna is entitled to receive from Anthem a reverse termination fee of $1.85 billion if the deal fails to win regulatory approval.

The U.S. Justice Department filed lawsuits last July asking a federal court to stop Anthem’s purchase of Cigna and Aetna’s acquisition of Humana, arguing that such consolidation among the largest health insurers was anti-competitive.

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