The striker wants to leave the club in January or in the summer, as he is disillusioned with life under Diego Simeone.
Felix, who is starring at the World Cup with Portugal, was linked to Manchester United last summer.
Per Spanish newspaper AS, Felix can leave Atleti if a club is willing to pay £86 million.
Felix does have a contract that runs until 2026, which means Atleti have no pressure to sell.
But the club does recognize that a poor start to the campaign at club level means his value has dropped.