Explain Suns General Manager Steve Kerr's Fine?

Steve Kerr, GM of the Suns, was fined for making a joke about LeBron James:

Worse still:

Can someone explain the NBA’s anti-tampering rules? I’m afraid I’m not all that familiar with sports labor rules.

Basically, you don’t talk about acquiring another team’s player, in any way, shape, or form.

Since LeBron is still technically under contract (free agency period has not yet begun), any comment by another GM will violate the tampering rules.

You’re not supposed to try to make deals outside of a certain window. The League is being kind of nitpicky but technically they were sending out a communication that they were interested in signing him and about what they might pay him.

Since the NBA season was not over at that point, LBJ was under contract to another team. It is against the rules to negotiate with players under contract to another team. At a certain point in the near future the contract with Cleveland will be over and any team can negotiate with LBJ for his services. This is done to prevent a team from promising to sign a player next year and that player then having divided loyalties.

Ah! That makes sense. I guess you don’t want an opposing team dangling a potentially lucrative contract over his head right before he plays against that team.