Shams Charania of Stadium and The Athletic on Friday reported the fine, which was levied under the league's anti-tampering rule.
Though comparing any current player to MJ immediately sparks debate, Rivers' remarks generated additional attention because the Clippers are expected to make a serious push to sign Leonard if he declines his player option for 2019-20 and becomes an unrestricted free agent this summer.
In early May, ESPN's Adrian Wojnarowski reported it seemed like the Clips would be the only team the 27-year-old Los Angeles area native would consider leaving the Raptors to join, even if he decided to accept meetings with other possible suitors in the offseason.
Josh Lewenberg @JLew1050
The Raptors have reached out to the league multiple times this season when they've felt the Clippers have crossed a line in their not-so-subtle pursuit of Leonard, I'm told. Would imagine today's $50K anti-tampering fine had as much to do with those incidents as Doc's comments
The NBA has made a concerted effort to enforce tampering rules in recent years.
In December, the league office sent a memo to all 30 teams to remind front offices about the guidelines and noted players' comments could also fall under the umbrella of tampering:
"In addition, recent attention has been paid to the issue of public comments by players. Generally speaking, it is not tampering when a player makes a comment about his interest in playing with another team's player. However, if there are other aggravating factors—such as sustained public recruiting or evidence that the player making such a comment is coordinating with his team—then there may be a basis for a tampering violation."
Meanwhile, Leonard, in his typically low-key fashion, has shrugged off any questions about his future throughout the season.
He helped the Raptors score a 118-109 victory over the Golden State Warriors in Game 1 of the 2019 NBA Finals on Thursday night.