I just don’t see how they wouldn’t be on the hook for the full amount.
I know it’s Rapoport, but this is the verified structure. The signing bonus is $9M, spread into two years. The second year is what you’d call the prorated bonus. When a player is either released or traded, the entire signing bonus is then due immediately, even if it was structured to be paid in installments (this is why the Steelers had to eat so much when they traded Brown.). Here’s an old article I found on it but thought it was commonly cited. There’s a difference between the cap hit (which I believe is the $9M due now, which impacts the cap) and the actual payments (which Kraft is disputing, though right now whether he pays or not, it would not impact the cap. That is, it may be credited back to the cap later but nonetheless would count until that determination is made.)
Contract Bonuses
Signing bonus:
The most common type of bonus, it’s typically reported at the time a contract is signed. While a player who receives an $8MM signing bonus on a new four-year contract generally receives that lump-sum payment up front, that $8MM actually prorates over the course of the deal for salary cap purposes. So it would count on the cap as $2MM per year, rather than $8MM in year one.
Signing bonuses prorate for up to a maximum of five years, so for a player inking a six- or seven-year deal with a $15MM signing bonus, that amount would count for $3MM against the cap for the first five seasons of the contract.
These prorated bonuses also represent guaranteed money, whereas other types of bonuses aren’t guaranteed at the time of the signing. That can make it tricky to release a player early on in a contract that included a large signing bonus. When a team releases a player, his remaining prorated bonus money “accelerates,” meaning it applies to his cap hit in the current league year. So if that aforementioned player who signed a four-year contract with an $8MM signing bonus is released in the second year of the deal, the remaining $6MM in prorated bonus money accelerates and counts against the cap for that season.
EDIT: I think this is what I’m missing and would explain it:
The effect of acceleration can be alleviated slightly by designating a player as a “June 1 cut,” or actually releasing the player after June 1. This allows the team to spread the so-called dead money remaining on a player’s contract over the course of two seasons rather than having it all apply to the current league year.