Descendants of vodka-makers to the Russian czars failed to persuade a federal judge in Delaware that Diageo Plc, the world’s biggest maker of alcoholic drinks, misappropriated the Smirnoff name for one of the U.S.’s most popular brands of vodka.

The Joint Stock Society, which identifies itself in court papers as the “Trade House of Descendants of Peter Smirnoff, Official Purveyor to the Imperial Court,” and its U.S. arm, the Russian American Spirits Co., filed suit in federal court in Wilmington in 1995 against Diageo and some of its units over the Smirnoff name. Diageo sells Smirnoff-brand vodka.