A flurry of lawsuits over a hotly disputed league table of vineyards is threatening the reputation of the Saint-Émilion châteaux, producers of some of the world's most famous wines.

At the heart of the row is the widely respected classification of les vins de Saint-Émilion, based on tests by a jury of experts under the supervision of the Ministry of Agriculture. Only a few dozen of Saint-Émilion's 800 or so vineyards make le classement and they are divided into three categories: premier grand cru classé A, premier grand cru classé B and grand cru classé.

The table, which was created in 1958, is revised every ten years. Promotion into le classement brings honours and wealth, with the value of the wine rising by between 10 and 50 per cent.

Relegation can spell financial disaster, with revenues slumping amid a sudden loss of custom. Jean-François Quenin, chairman of the Saint-Émilion Wine Council, told The Times: “There is a lot of money in play and that's why the debate is so intense.”

When the latest classification was drawn up in 2006, it featured 61 châteaux, including six newcomers. Two others were promoted from grand cru classé to premier grand cru classé B.

But 11 vineyards lost their place among the chosen few, and seven of these went to court to challenge the decision. After two years of legal argument Bordeaux's Administrative Tribunal upheld their claim this summer, ruling that the jury had failed to taste all the wines under the same conditions and had thereby created an uneven playing field.

The court quashed the 2006 classement, with the result that the eight promoted vineyards were automatically relegated again and the 11 that had been relegated were reinstated.

“This is a great moment of happiness for us,” said Philippe Genevey, who runs Château La Marzelle, which regained its grand cru classé status as a consequence of the verdict.

The losers were furious and are backing an appeal. Xavier Pariente, owner of Château Troplong-Mondot, said that he had spent “dozens of millions of euros” to win a place in the grand cru classé B category only for his efforts to be ruined.

“That's almost 20 years of hard work and investment by all the personnel here wiped out at the stroke of a pen. It frightens me and it revolts me.”

The legal battle has left châteaux owners unsure how to label their bottles. Nicolas Thienpont, who runs Château Pavie-Macquin, which was also named a premier grand cru classé B in the 2006 table, said that he had bottled and labelled his wine and put it in crates ready for export to the US.

Now he may have to stick a second label on the bottles saying that his classé B status depends on the outcome of the appeal. “It's ridiculous, irritating and very costly,” he said.

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