More correctly, he has filed a grievance with the league. It may eventually turn to litigation, but right now, it is the same as employee grievances filed in any other workplace.I heard on the radio that Käpernick is now suing the NFL. He claims that he's been blacklisted. He says teams indicated (some how, some way) that they we interested in him and then, nothing. He claims NFL management is keeping teams from offering him a contract.
Personally, I don't think Goodell has the will or the desire to do that, but we'll see. I'll bet Goodell wishes he'd have sat on Kapernick when this started last season, before it got out of control. Too late now.
It does essentially end his career with the league. Ironically, he might actually have had a shot with someone like the Packers where the QB has gone down for a season. The earlier issue with the Titans was not a likely landing spot since Mariota was apt to be out for perhaps two games and nobody is going to hire Kaepernick to carry a clipboard.
What he fails to realize is that nobody wants a polarizing cancer in the locker room. Teams learned that when they took a chance on wife-beating pieces of crap (Greg Hardy) and saw the PR fallout. And now that the league is taking a PR beating (no pun intended), they don't want someone that is going to piss off the fan willing to dump a few hundred per seat eight weeks out of the season (more if food and parking is included in the average weekly expenditure).
He is learning what others through the years have learned in a variety of workplaces...you can say whatever you want, but you do not get to do it on the clock and, oh by the way, you don't get to do it without fear of consequence attaching.