In yet another setback for the NFL as it seeks to end a years-long legal battle over concussions, a federal judge on Monday declined for a second time to sign off on a proposed settlement between the league and thousands of former players who have filed suit over past head injuries.

The decision by U.S. District Judge Anita Brody marks the second time that the agreement — which would pay out approximately $1 billion over 65 years — has failed to win final approval. In a three-page order issued just a day after Super Bowl XLIX, Brody requested the two sides do more to compensate players suffering from symptoms of chronic traumatic encephalopathy (CTE), a degenerative brain disease that has been discovered in 76 of 79 NFL players posthumously tested at the nation’s leading brain bank for traumatic brain injury.

Under the outline of the proposed settlement, beneficiaries of a player found to have died from CTE would be eligible for a payment of $4 million. The catch, however, is that the deceased player would have needed to have died prior to the settlement’s preliminary approval date of July 7, 2014. That condition, Brody said, should be extended until the date of the agreement’s final approval.

In addition, Brody said the settlement should provide players credit for any time spent playing in the NFL’s European league. She also asked that players be granted “reasonable accommodation” if they are unable to supply medical records showing they suffer from one of several qualifying conditions, including Alzheimer’s and Lou Gehrig’s disease.

Such changes, Brody wrote, “would enhance the fairness, reasonableness and adequacy” of the agreement.

“The judge did not reject the settlement,” Brian McCarthy, an NFL spokesman, said in an e-mail to Bloomberg News. “The judge asked both sides to address several issues before she grants final approval.”

The two sides will have until Feb. 13 to address the judge’s requests, though there is little guarantee that future revisions will necessarily lead to final approval. In January 2014, Brody dealt the agreement its first major setback, ruling that the amount set aside for damages may not be enough to compensate every player who may one day require assistance. Following that ruling, the NFL removed a cap of $675 million that it had previously set on damages.

In all, more than 4,500 players have signed onto the suit, but according to Brody, as many as 20,000 former players may one day be eligible for payment under the deal. While the league has questioned that figure, by its own estimates, nearly one-in-three former players may develop one of the brain conditions covered by the agreement.

Here’s a closer look at how the proposed settlement would work:

Jason M. Breslow, Former Digital Editor

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