巧了，這兩天剛剛在讀這類體育賽事經濟機制的論文。
這篇名叫「The Economic Design of Sporting Contests」的綜述就提到了這個。
對於北美類別的聯盟，他給的共同描述是這樣的：
1. Organizational independence of the domestic major leagues
2. a fixed number of teams
3. entry through the sale of expansion franchises
4. exclusive territories and franchise mobility
5. draft rules giving teams monopsony rights in player acquisition
6. roster limits
7. low player mobility and limited player trading
