Former Norwich City manager Paul Lambert is suing the club for around £2m, according to chairman Alan Bowkett.
The Scot guided the Canaries from League One to the Premier League in three seasons during a three-year spell at Carrow Road before joining Aston Villa over the summer.
Bowkett told supporters at a Fans Forum meeting on Thursday that the 43-year-old was now trying to sue his former employers for breach of contract.
Neither Lambert or Aston Villa have commented on the claim.