The Argentine died when the plane carrying him from Nantes to Cardiff crashed in the English Channel, shortly after signing for the English Premier League side.
His body was later recovered from the wreckage, while pilot David Ibbotson remains missing.
Cardiff City chairman Mehmet Dalman has said the club will pay the 15 million pounds transfer fee to Nantes for Emiliano Sala “if contractually obliged”.
The clubs had become involved in a dispute over when the first instalment of the fee should be paid although Cardiff City manager Neil Warnock said last week he believed that Nantes had agreed to an extension.
"We can confirm that we have received yesterday evening a claim of a contractual nature from FC Nantes against Cardiff City in connection with the transfer of Emiliano Sala," said a FIFA spokesperson.
"We are looking into the matter and consequently we have no further comments at this stage."
(Writing by Brian Homewood; Additional reporting by Shrivathsa Sridhar; Editing by Toby Davis)
