The NBA’s Collective Bargaining Agreement includes a rule that states players who are acquired using an exception (ie. not using cap space) can’t be aggregated in a second trade for two months after the original deal.
Aggregating a player in a trade refers to the act of combining his contract with another player’s contract for salary-matching purposes. For instance, an over-the-cap team can’t trade a player with a $5MM salary straight up for a player with a $13MM salary. But if the team aggregates that player with a second player who also earns $5MM, the deal would work.
The rule against including a player in an aggregated trade for two months after he’s acquired doesn’t preclude the player’s team from adding him to a multi-player deal. His salary simply can’t be combined upon with another player’s for matching purposes in such a trade.
For instance, even if a player earning a minimum salary can’t be aggregated in a trade, his team could still include him in a swap involving a pair of $10MM players, since his minimum-salary cap hit wouldn’t be needed for salary matching.
With those rules in mind, here’s the list of players who have been acquired using a cap exception within the last two months and can’t be aggregated in a deadline trade this season: