Fiorentina accused Chelsea of committing a “breach of contract” after they loaned the 23-year-old to Serie A rivals Roma for the 2015-2016 season.
Salah spent part of the 2014-15 season on loan at Fiorentina, who claimed they had a deal in place with Chelsea for the Egyptian international to return for an additional season.
“We can confirm that the dispute resolution chamber (DRC) dealt with the dispute opposing the Italian club, ACF Fiorentina, to the player, Mohamed Salah Ghaly, and the English club, Chelsea FC,” a FIFA spokesperson told British media.
“The claim of the Italian club was rejected. Since the decision is not yet final and binding, we are not in a position to comment on it any further.”
Salah made 34 league appearances last season for Roma who finished third in the Serie A behind Napoli and Juventus.