By Jonathan Stempel

NEW YORK (Reuters) – A U.S. judge on Monday dismissed long-running litigation by investors who accused HSBC Holdings Plc and Bank of Nova Scotia of conspiring to fix silver prices.

U.S. District Judge Valerie Caproni in Manhattan said the investors lacked legal standing to pursue federal antitrust claims under the Sherman Act, or claims under the federal Commodity Exchange Act.

Investors had accused HSBC, Scotiabank and Deutsche Bank AG of manipulating silver prices from 2007 to 2013, saying they had “smoking gun” evidence of a price-fixing conspiracy among those banks and several other silver market makers.

The litigation began in 2014, and Deutsche Bank settled for $38 million two years later.

In a 24-page decision, Caproni found the investors unable to trace their losses to banks’ alleged effort to depress the Fix, which set benchmark prices for silver bars, and trade derivatives based on advance knowledge of the Fix price.

Caproni said the investors did not show it was “plausible, as opposed to merely possible” that distorted pricing affected their trades, and said any damages were “too speculative.”

The judge also said the investors were not “efficient enforcers” of their private antitrust claims, unlike people who might have sold silver at the Fix price.

Lawyers for the investors did not immediately respond to requests for comment. The banks and their lawyers did not immediately respond to similar requests.

Caproni dismissed the lawsuit with prejudice, meaning it cannot be brought again.

She had in 2016 let the case proceed, but said recent decisions by the federal appeals court in Manhattan have clarified when private plaintiffs can bring antitrust and commodities act claims.

The cases is In re London Silver Fixing Ltd Antitrust Litigation, U.S. District Court, Southern District of New York, No. 14-md-02573.

(Reporting by Jonathan Stempel in New York; Editing by Bill Berkrot)

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