The club want to make sure that further signings can play Champions League in January 2016
According to the newspaper Mundo Deportivo, FC Barcelona's board want to include a new clause in the next signings to make sure they can play Champions League from January 2016 on, when the FIFA ban is over. Since the club can sign players but not register them, they are considering sending them on loan until 2016, but with a clause that allow them play Champions League with Barça when they come back.
UEFA's rules and regulations say no footballer who has played the group stage with a team can play the next rounds with a different club. That's why Barça might include a clause that would ban players on loan to play Champions League. This would mean that Barça should have to convince the player and the club, offering something to compensate.
Apart from that, the Catalan club would also have to contract a medical insurance for the player, since they could not control his physical conditions.