
The 25-year-old joined United from Sporting in January for an initial fee of €55 million and has registered three goals and four assists in nine games.
Sky Sports reported that Italy’s Sampdoria inserted a 10% sell-on clause on any profit Sporting made on Fernandes when they sold him in 2017.
However, the Portuguese club says that clause is null and void as the playmaker signed a fresh deal in June 2018 after terminating the original one.
“We can confirm that on April 3 the Italian club Sampdoria lodged a claim with Fifa against the Portuguese club Sporting Clube de Portugal related to financial obligations set out in the contract corresponding to the transfer of … Fernandes,” Fifa said in a statement released to British media.
Fernandes was one of a number of players who terminated their contracts at Sporting after a group of some 50 masked men attacked players and staff at the club’s training complex in 2018.
He later decided to remain with the club.