Non-NBA pro teams "understand they're in some respects a farm league for the best players," leading those foreign teams to craft buyout agreements into players' contracts that must be paid before they can play on an NBA team, said Larry Coon, an expert in the NBA's collective bargaining agreement who runs NBA Salary Cap FAQ.
Additionally, the rules of Federation Internationale de Basketball (FIBA), the sport's international governing body, require players to obtain a clearance letter from the federation in the country where they're under contract. There are 214 national FIBA federations.
The NBA allows teams to pay an "excluded amount" of money toward a buyout without it counting against their salary caps. The limit increases each year and will reach $600,000 for the 2014-2015 season, Coon said.
Anything above $600,000 falls on individual players.
"Essentially, it comes out of their [NBA] contracts," Coon said.
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For example, the Chicago Bulls picked Nikola Mirotic, a center who plays for Spanish powerhouse Real Madrid, with the 23rd pick in the 2011 draft. Mirotic has yet to land in Chicago, but he would pay $2.9 million of his $3.5 million buyout if he debuted this season, Coon said.
The NBA's rookie pay scale limits salaries for first-round picks, offering little flexibility for players and teams, who often package buyouts into players' signing bonuses. If Mirotic had signed with the Bulls immediately, his first-year base salary would have topped out at only $1,003,800—versus his part of a buyout, which would be almost three times that amount.
Teams will often pass or trade down to the second round, where the scale doesn't apply, to open more flexibility in structuring contracts for players responsible for a buyout, he said.
Teams can avoid the rookie scale, though, if players wait more than three years to sign, which the Bulls may choose to do with Mirotic, Coon said.