After years of negotiations, a federal judge on Wednesday approved a settlement in the high-profile concussion lawsuit brought by more than 4,500 former players against the NFL, the Associated Press reports.

The settlement, which could amount to more than $1 billion, is said to cover individual players for up to $5 million if they prove to have certain neurological conditions, according to the New York Times. The settlement also provides $10 million to go to concussion education.

The plaintiffs’ counsel views Wednesday’s finalized settlement as a success.

“Nearly four years ago, retired NFL players embarked on a mission that many thought to be impossible: to obtain security and care for the devastating neurocognitive injuries they were experiencing,” Christopher Seeger and Sol Weiss, co-lead counsel for the players, said in a statement on Wednesday.

They added: “Today, these courageous men and their families have made history. Despite the difficult health situations retired players face today, and that many more will unfortunately face in the future, they can take comfort that this settlement’s benefits will be available soon, and will last for decades to come.”

The NFL and the former players first reached a settlement in August 2013, which was capped at $765 million. U.S. District Judge Anita Brody, however, withheld her approval at that point, ruling that the agreed-upon amount may be insufficient to cover payouts, tests and treatments into the future. Eventually the two sides agreed to uncap the settlement amount.

In February, Brody asked the two sides to amend and expand additional settlement terms, including making changes that “would enhance the fairness, reasonableness, and adequacy” of the payments to players. Per The Washington Post’s Rick Maese, who wrote in February:

“In addition to clarifying some language, Brody instructed the attorneys to give credit to players who competed in NFL Europe and the World League of American Football and to extend benefits to any ex-players who were diagnosed with chronic traumatic encephalopathy (CTE) after death between preliminary approval and final approval.”

While the settlement is final, payments to the affected players could take months or years to come as the appeals process plays out.

Roughly 200 players opted out of the class action lawsuit, meaning they could pursue individual suits against the league.