In the 1855 classification Mouton received only second growth status, prompting the following inscription on Mouton labels: Premier ne puis, second ne daigne, Mouton suis, or 'First I cannot be, second I do not deign to be, I am Mouton. It was clear from the great vintages produced in the 1860s and 1870s that the 1855 classification was already outdated, and that change was long overdue. Finally in 1973, thanks to the tireless campaigning of that the late Baron Philippe de Rothschild, the then Minister of Agriculture, Jacques Chirac, passed a decree conferring the status of first growth upon Mouton-Rothschild. At last the wrong had been righted, and Mouton's labels bore a new inscription: Premier je suis, second je fus. Mouton ne change, or First I am, second I was. I Mouton, do not change. Baron Rothschild was the only person ever able to effectuate a change in the 1855 Médoc classification.

Chateau Mouton today remains faithful to its classification and reputation, consistently turning out an opulently rich and remarkably deep and exotic style of wine. It has often produced the wine of the vintage, and there can be no doubt that its position as a first growth is well merited. Wines from the late 1940s, in the immediate post-war years, are legendary, and those being produced today are very much in the same vein.