Swansea City's sale of Michel Vorm to Tottenham Hotspur will be subject to a hearing at the Court of Arbitration for Sport on Friday.
Vorm joined Tottenham from Swansea in a deal which also took Ben Davies to Spurs while Gylfi Sigurdsson went the other way, as part of the transaction.
The swap deal meant that Dutch club FC Utrecht did not receive any funds which they believed they were entitled to, as they had a 30% sell-on clause included when they sold Vorm to Swansea for £1.5million back in 2011.
Utrecht have been left fuming as a result and have now taken the case to the Court of Arbitration of Sport.