Yes if you have him protected you keep him. If you don't and two teams choose him, the one with most appearances for claims him
Almost....
The teams who have players with the most appearances with their assigned clubs can start building their teams.
Managers from top 7 teams can 2 protect two players who played at their clubs who have the most appearances in their careers at that club
Friday is a day where 2nd choice or 3rd choice players get sorted out even though they are quality. Let's use Liverpool for example.
Xabi Alonso just for shit and giggles
He is first a Real Madrid player - since he had 158 appearances with them
Of course there are so many players for Real that if he is not protected then he would fall to Liverpool
Of course there so many players for Liverpool he would fall to Real Sociedad (who is not yet in the ECL)
So then he would fall to Bayern.
So since he is last in appearance with Bayern, technically Bayern could protect him but would they?
Ultimately, the teams who have to protect players will only have two players (and they will be sure things).
So LFC does not want to waste a valuable protection on Alonso, neither does Bayern.
But Alonso could fall to these teams as the manager of Real will have choices to make at different position because of the decade rule.