A federal judge has dismissed an antitrust class action accusing Citigroup, Morgan Stanley and other global banks of inflating the prices of U.K. government bonds sold in the United States, ruling the plaintiffs have failed to allege a plausible price-fixing conspiracy.

U.S. District Judge John G. Koeltl of the Southern District of New York dismissed the complaint without prejudice, citing deficiencies in the lawsuit filed by an Oklahoma public pension fund.