An attorney for the NBA revealed in testimony that the league would require 1% of every bet placed on the league to become a partner in nationally-legalized sports gambling, according to ESPN.

Why it matters: The Supreme Court is currently hearing a case that would determine whether the federal ban on sports betting outside of Nevada violates states' rights. The NBA, NFL, MLB, NHL and NCAA have spent millions in legal fees to prevent the expansion of sports gambling, per ESPN, but a flip by the NBA could pave the road to legalization for an industry estimated to be worth hundreds of billions.

The American Gaming Association, meanwhile, argues that a 1% fee on legally-placed bets would amount to 20 to 29% of total revenue. This would create economic pressure on oddsmakers that the AGA says "would drive consumers back to the black market."