Some negotiators make mediation-arbitration contingencies in the event of disagreement, thereby promising in advance to avoid legal action. For example, in 2013 a federal judge overseeing a case brought by thousands of former National Football League (NFL) players accusing the league of hiding the dangers of concussions ordered both sides to mediation to encourage both parties to come to agreement without further litigation. From these mediated talks, the NFL reached a tentative $765 million settlement over concussion-related brain injuries among its 18,000 retired players, agreeing to compensate victims, pay for medical exams, legal costs, and underwrite research.