Casino's shareholders have granted Fimalac, the French financial group owned by billionaire Marc Ladreit de Lacharriere, a seat on the board of the French retailer.
Some 93.35% of votes cast at Casino's annual shareholder meeting on Wednesday approved a resolution appointing Fimalac deputy CEO Thomas Piquemal to the board.
Fimalac, which has a 2.6% stake in Casino, agreed in March to provide new financing facilities for Rallye, the parent company of Casino, which has been under pressure to cut its debts.
By bringing in new financing from Fimalac, Casino ended a previous arrangement with Czech businessman Daniel Kretinsky, who had initially been offered a Casino board seat.
VESA Equity Investment, controlled by Kretinsky, had raised its stake in Casino to 6.88% of the capital and 5.17% of the voting rights in March.
But in April, VESA lowered its stake in Casino to 4.99% of the voting rights through the sale of Casino shares.