The Royal Spanish Football Federation (RFEF), which is the actual name somehow, officially fined Barcelona €300 over their transfer of Antoine Griezmann. According to the RFEF, Barcelona committed a minor infraction when moving in on Griezmann while he was still at Atletico Madrid.
“This committee is aware that the payment of €300, beyond it’s purely symbolic gesture, will not contribute to the club being punished in this case and probably other clubs that may be in this situation in the future, to fit their conduct within the required rules.”
RFEF | Source
Barcelona signed Griezmann in July, and Atletico are saying that Barca didn’t pay the release clause they should have. Officially, Barcelona violated article 126 of the from the disciplinary code. Atletico have 10 days to appeal the ruling, which I would expect them to do given the pretty low payment.