The Wales international's transfer has been called into question after three MEPs wrote to the EC asking for an investigation into the financing arrangement behind the deal.
MEP Sander Loones has called on the European Commission to mount an investigation into the financing behind Gareth Bale's world-record transfer from Tottenham to Real Madrid in 2013.
Loones and fellow European Parliament members Daniel Dalton and Ramon Tremosa wrote to the Commission with concerns that Spanish banks bailed out by European tax payers provided guarantees for the fee paid to sign the Welshman.
In 2013, Dutch MEP Derk-Jan Eppink raised questions over the financing arrangement behind the deal, and the trio have reignited the issue with their submission to the executive body of the European Union.