Swiss side FC Sion are still awaiting a decision from the Court of Arbitration for Sport over their reinstatement into the Europa League, but have decided to press ahead with legal action against the French FA for loss of earnings.
Sion were banned from competing in the tournament by UEFA - for fielding ineligible players that were signed during a transfer ban - and Celtic took their place.
However, Sion have fought the decision after a Swiss court ruled that the club should be allowed to participate and have first turned their attention to the French FA for sanctioning Rennes' two games with Celtic.
"Our lawyer for European cases, Mr Dupont, started this action against the French Football Federation because of the non-organisation of the games Rennes v Sion," a club spokesman told STV.
"The Swiss civic court ordered for Sion to be reintegrated immediately. They did not do this, and we need to repair these damages. We are planning something for every federation. This would be for lost prize money and other matters."