The conviction brought suspended sentences and fines
A dozen French winemakers and traders have been found guilty of a massive scam to sell 18 million bottles of fake Pinot Noir to a leading US buyer.
The judge in Carcassonne, south-west France, said the producers and traders had severely damaged the reputation of the Languedoc region.
The 12 more than doubled profits passing off the wine to E and J Gallo under its Red Bicyclette brand.
E and J Gallo was not involved in the court case.
In a statement on its website it said it was "deeply disappointed" to learn its supplier, Sieur d'Arques, had been found guilty of selling falsely labelled French Pinot Noir.
The court ruled the 12 had deliberately and repeatedly mislabelled the wine as one of the more expensive varieties of grape in order to get a better price from E and J Gallo.
The Red Bicyclette Pinot Noir single grape wine is hugely popular in the United States.
French Customs officers spotted the swindle and called in investigators.
They found the amount of Pinot Noir being sold to Gallo was far more than the region produced.
Some of those in the scandal were not even Pinot Noir producers.
The judge handed out suspended jail sentences ranging from one month to six months for the most prominent wine trader and ordered all the defendants to pay fines.
The fines ranged from 1,500 euros ($2,050; £1,300) to the top figure of 180,000 euros ($247,050; £156,500) for Sieur d'Arques. The judge said that the accused together made seven million euros in profits from the scam.
The judge said: "The scale of the fraud caused severe damage for the wines of the Languedoc for which the United States is an important outlet."
A lawyer for Sieur d'Arques, Jean-Marie Bourland, told Agence France-Presse: "There is no prejudice. Not a single American consumer complained."
A lawyer for three other defendants argued his clients had delivered a wine that had Pinot Noir characteristics.
E and J Gallo said it was no longer selling any of the wine to its customers.