NEW YORK (Reuters) - A U.S. appeals court on Wednesday revived three private antitrust lawsuits accusing JPMorgan Chase & Co JPM.N of rigging a market for silver futures contracts traded on COMEX.

A view of the exterior of the JP Morgan Chase & Co. corporate headquarters in New York City May 20, 2015. REUTERS/Mike Segar/Files

The 2nd U.S. Circuit Court of Appeals in New York said a lower court judge held hedge fund manager Daniel Shak and two other traders to an excessively high legal standard when deciding last June 29 to dismiss their complaints.

Shak, Mark Grumet and Thomas Wacker accused the largest U.S. bank of having in late 2010 and early 2011 placed artificial bids on the trading floor, harangued staff at metals market COMEX to obtain prices it wanted, and made misrepresentations to a committee that set settlement prices.

The traders said this forced them to post more capital to support their positions in silver futures spreads, and ultimately to liquidate them at heavy losses.

Shak is also known for playing high-stakes poker.

In Wednesday’s unsigned decision, a three-judge panel rejected U.S. District Judge Paul Engelmayer’s finding that the traders did not adequately show that JPMorgan made “uneconomic” bids, or intended to rig the market.

The panel said Engelmayer demanded too much detail, including specific transaction terms and the identities of JPMorgan’s counterparties.

It also said Engelmayer engaged in “impermissible fact-finding” by objecting to the plaintiffs’ use of the 12-month Silver Indicative Forward Mid Rates as a benchmark for determining proper spread levels.

“We hold that plaintiffs adequately pleaded ‘willful acquisition or maintenance of monopoly power’ to sustain an antitrust claim,” the appeals court panel said.

JPMorgan spokesman Brian Marchiony declined to comment on the ruling.

A lawyer for the traders, David Kovel, said: “We are happy with the decision and look forward to having the claims heard.”

JPMorgan has prevailed in other silver litigation, including in 2014 when the 2nd Circuit rejected class-action claims that the New York-based bank intended to drive prices down.

The case is Wacker et al v. JPMorgan Chase & Co et al, 2nd U.S. Circuit Court of Appeals, Nos. 16-2482, 16-2484, 16-2530.