Chelsea's Premier League rivals are questioning whether owner Roman Abramovich can act on his promise to write off the club's £1.5bn debt without breaking profit and sustainability rules.
Chelsea have been clear that he can but some clubs want the issue investigated, which could ultimately lead to a points deduction or the debt having to be repaid, complicating an already-complex transaction. The Premier League board would ultimately make the decision whether to charge the club.
The Premier League's Profit and Sustainability rules are its version of UEFA's Financial Fair Play rules, though far more generous.