European soccer clubs have sported sizable corporate logos on their uniforms for decades. Not so the teams of the North American major leagues--the NBA, MLB, the NFL and the NHL--which have long considered their jerseys too sacred to be tainted by them.
Now the NBA wants to scrap that tradition. In July deputy commissioner Adam Silver announced plans to allow 2.5-in.-by-2.5-in. ads just below the left shoulder on team jerseys. The move--which awaits formal approval in September--would create a windfall for the NBA, generating as much as $100 million in revenue per year. If the deal goes through, other American big-four...