Real Madrid president Florentino Perez insists Kaka is not for sale.
Galatasaray have declared interest in buying Kaka when the market reopens in January.
"We've never said that we wanted to sell Kaka, and we've never tried to sell him," Perez told supporters at an assembly of club members.
He added: "Kaka has earned us lots of money.
"He came to the club three years ago as an investment that has brought us big profits. Economically speaking, it's a transfer that has borne fruits."