Former Renault team boss Flavio Briatore said it was very probable he would take legal action against Nelson Piquet after having his life ban from Formula One overturned.
Briatore was banned in September by the FIA after former Renault driver Piquet told the ruling body he had been ordered to crash deliberately at the 2008 Singapore Grand Prix to help his Spanish team mate Fernando Alonso win the race.
A French court ruled on Tuesday that the punishment was illegally imposed by the sport's governing body.
Asked about now suing Piquet, Briatore told Wednesday's Gazzetta dello Sport: "Very probably. I won't forget the pain I've suffered in a day."
The FIA's lawyer Jean-Francois Prat told Reuters the FIA would "very likely" appeal the decision to overturn the ban.
The governing body also said the decision was not enforceable until all appeal options had been exhausted and noted the court had not reversed the finding that Briatore had conspired to cause an intentional crash.
Despite this, Briatore said he would continue to manage F1 drivers "like always" and threatened to go to court against those who had left him.
"Apart from Heikki Kovalainen and Lucas Di Grassi, my relationship with the other drivers has never changed," he said.
"Now we will look at the situation with lawyers to see if we can take legal action against those who have broken contracts with us."
The flamboyant multi-millionaire, who has said he will take his time deciding on his general future in Formula One, heavily criticised former FIA president and long-time enemy Max Mosley across Italian media and said his health had suffered.
"Champagne? No, I opened a Coca Cola because I'm on a diet. I've been eating rubbish for three months," said the 59-year-old, who will become a father again soon.
"We still haven't agreed a name. It certainly won't be called Max!"