UEFA are considering banning from the Champions League players whose transfer rights are owned by third parties. Gianni Infantino, the general secretary of UEFA, said the practice - which is already outlawed in the Premier League and France's Ligue 1 - could not be allowed to continue.
"We will ourselves look into this matter because it cannot continue in this manner."
Third-party ownership is allowed in Spain, Italy, Germany and Portugal.
Infantino said he would "certainly look into" the possibility of banning third party-owned players from the Champions League and Europa League. "This kind of player ownership is a growing threat," he told Bloomberg.