Former professional football ­players involved in the NFL concussion litigation have sued their former ­attorneys in federal court over liens placed or intended to be placed on the players’ individual cuts of the league’s $1 billion settlement.

In their complaint, the seven plaintiffs—Gale Sayers, Lem Barney, Thomas Skladany, Thomas Vaughn, Jerry Rush, Kenneth Callicutt and Eric Hipple—asked the court to declare that the law firms formerly representing them in the concussion litigation are not entitled to liens on the players’ recovery. Sayers and Barney are members of the Pro Football Hall of Fame.