A federal appeals court on Monday upheld the National Football League's estimated $1 billion concussion settlement with retired players, calling the agreement imperfect but fair.
A small group of players had objected to the deal, which was approved in April 2015 by U.S. District Judge Anita Brody in Philadelphia, because it did not cover potential victims of a degenerative brain disease that scientists have linked to repeated blows to the head.
"It is the nature of a settlement that some will be dissatisfied with the ultimate result," Circuit Judge Thomas Ambro wrote for a three-judge panel of the 3rd U.S. Circuit Court of Appeals in Philadelphia. "But they risk making the perfect the enemy of the good."
Representatives of the NFL, the objecting players and the retirees who signed on to the deal did not immediately respond to requests for comment.
The settlement calls for payments of up to $5 million each to former players diagnosed with certain neurological disorders, but it does not address chronic traumatic encephalopathy (CTE), which some researchers say can be caused by concussions.
The lawsuit was brought on behalf of more than 5,000 retired players, though the settlement could cover more than 21,000 former players, according to the court.
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NFL's $1 billion concussion settlement upheld by U.S. appeals court
CHARLOTTE, NC - JANUARY 17: Marshawn Lynch #24 of the Seattle Seahawks looks on before the NFC Divisional Playoff Game against the Carolina Panthers at Bank of America Stadium on January 17, 2016 in Charlotte, North Carolina. (Photo by Ronald C. Modra/Sports Imagery/Getty Images)
FOXBORO, MA - DECEMBER 24: Jerod Mayo #51 of the New England Patriots reacts after he sacked Matt Moore #8 of the Miami Dolphins in the second half at Gillette Stadium on December 24, 2011 in Foxboro, Massachusetts. (Photo by Jim Rogash/Getty Images)
RETIRING A PATRIOT.
BALTIMORE, MD - DECEMBER 27, 2015: Tight end Heath Miller #83 of the Pittsburgh Steelers watches the action from the sideline during a game against the Baltimore Ravens on December 27, 2015 at M&T Bank Stadium in Baltimore, Maryland. Baltimore won 20-17. (Photo by: Nick Cammett/Diamond Images/Getty Images)
After 11 seasons and two Lombardi trophies, Heath Miller retires in Black & Gold.
📰 | https://t.co/rUr3Yf1XPd https://t.co/RWH0yFgWab
DETROIT, MI - OCTOBER 25: Calvin Johnson #81 of the Detroit Lions looks on from the sidelines during the game against the Minnesota Vikings at Ford Field on October 25, 2015 in Detroit, Michigan. The Vikings defeated the Lions 28-19. (Photo by Mark Cunningham/Detroit Lions/Getty Images)
Calvin Johnson retires from the National Football League: https://t.co/8YgcYxLjNS https://t.co/IdC1yIMX8R
CHARLOTTE, NC - OCTOBER 25: Jared Allen #69 of the Carolina Panthers reacts after a sack of Sam Bradford #7 of the Philadelphia Eagles during their game at Bank of America Stadium on October 25, 2015 in Charlotte, North Carolina. The Panthers won 27-16. (Photo by Grant Halverson/Getty Images)
Riding off into the sunset https://t.co/wZXovseGKS
MINNEAPOLIS, MN - AUGUST 8: Corey Wootton #99 of the Minnesota Vikings looks on during the fourth quarter of the game against the Oakland Raiders on August 8, 2014 at TCF Bank Stadium in Minneapolis, Minnesota. The Vikings defeated the Raiders 10-6. (Photo by Hannah Foslien/Getty Images)
Thank you all for the support! https://t.co/wHQqWkAirF
DETROIT, MI - DECEMBER 07: Logan Mankins #70 of the Tampa Bay Buccaneers warms up prior to the start of the game gainst the Detroit Lions at Ford Field on December 7, 2014 in Detroit, Michigan. The Lions defeated the Buccaneers 34-17. (Photo by Leon Halip/Getty Images)
Ex-#Patriots & #Bucs G Logan Mankins was tough, nasty, played through the whistle… and is a great dude when the play ends. One of a kind.
JACKSONVILLE, FL - DECEMBER 13: Matt Hasselbeck #8 of the Indianapolis Colts drops back to pass during a game against the Jacksonville Jaguars at EverBank Field on December 13, 2015 in Jacksonville, Florida. The Jaguars defeated the Colts 51-16. (Photo by Stacy Revere/Getty Images)
It has been an honor and a pleasure.
EAST RUTHERFORD, NJ - DECEMBER 22: (NEW YORK DAILIES OUT) D'Brickashaw Ferguson #60 of the New York Jets greets fans after a game against the Cleveland Browns on December 22, 2013 at MetLife Stadium in East Rutherford, New Jersey. The Jets defeated the Browns 24-13. (Photo by Jim McIsaac/Getty Images)
Thank you for the numerous messages of support. It has been a blessing to be apart of the NYJ. My letter to you https://t.co/hcIRk41QtM
GLENDALE, AZ - AUGUST 24: Defensive tackle Darnell Dockett #90 of the Arizona Cardinals watches from the sidelines during the preseason NFL game against the San Diego Chargers at the University of Phoenix Stadium on August 24, 2013 in Glendale, Arizona. (Photo by Christian Petersen/Getty Images)
To the founder of the #BirdGang, @ddockett, congrats on a great career! #ThanksNineO
ORCHARD PARK, NY - SEPTEMBER 13: Percy Harvin #18 of the Buffalo Bills celebrates a touchdown reception against the Indianapolis Colts on September 13, 2015 at Ralph Wilson Stadium in Orchard Park, New York. Buffalo defeats Indianapolis 27-14. (Photo by Brett Carlsen/Getty Images)
Percy Harvin told the Bills he is retiring, per source.
SEATTLE, WA - OCTOBER 18: Wide receiver Ricardo Lockette #83 of the Seattle Seahawks gestures to the crowd during the game against the Carolina Panthers at CenturyLink Field on October 18, 2015 in Seattle, Washington. (Photo by Otto Greule Jr/Getty Images)
I just wanted to make my teammates, family, & The 12th Man proud!!!! #weallwegot
Thank you, Peyton, and congratulations on your magnificent 18-year NFL career! https://t.co/YdMt19tQ2i https://t.co/jYDXpMmlUA
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Roughly 200 retirees objected to the agreement, saying it did not account for players yet to be diagnosed with CTE. They also argued the deal unfairly favored currently injured retirees and left thousands of former players who have not yet been diagnosed with neurological diseases without a remedy.
CTE has been discovered during autopsies for several former players, including Hall of Fame linebacker Junior Seau and Pro Bowl safety Dave Duerson, who both committed suicide. In March, the NFL for the first time acknowledged a link between football and CTE.
But the appeals court noted that the research surrounding CTE is still nascent, with no current way to test for the disease while an individual is still alive. It also said many of the symptoms associated with CTE, such as memory loss, are eligible for compensation under the settlement.
(Additional reporting by Jonathan Stempel; Editing by James Dalgleish)