Earlier this year, Deutsche Bank (DB) settled a lawsuit alleging the investment bank of rigging silver prices. Now plaintiffs in the suit are going after several other banks, which they believe were parties to a massive conspiracy to manipulate the metal’s value in open markets.

“Plaintiffs are now able to plead with direct, 'smoking gun' evidence, including secret electronic chats involving silver traders and submitters across a number of financial institutions, a multi-year, well-coordinated, and wide-ranging conspiracy to rig the prices of silver and silver financial instruments that far surpasses the conspiracy alleged earlier by Plaintiffs when they lacked access to such information,” claimed the plaintiffs in a document filed with the United States District Court in New York.

The banks accused of colluding to fix oil prices include HSBC Holdings plc (HSBC), Barclays plc (BCS), UBS Group Inc. (UBS) and Bank of Nova Scotia (BNS).

The banks are accused of “coordinating trades in advance of the daily fixing phone call” as well as manipulating the spot market for silver, conspiring to fix the spread between bid and ask prices, using “manipulative trading strategies” to influence the price of silver, sharing proprietary information, triggering clients’ stop-loss orders, and front running silver orders.

The new accusations are based on released documents from Deutsche Bank, which alleged show collusion between various investment bank traders to manipulate silver prices in a wide-ranging global conspiracy.

The plaintiffs are asking the courts to allow them to file a new lawsuit against the named banks. Shares in the investment banks were little moved on the news, and silver prices in the spot market were down 0.3% in early-morning trading on Friday.

The iShares Silver Trust (SLV) has skyrocketed in 2016, rising over 22% year-to-date after seeing three years of heavy declines.

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