JPMorgan, HSBC sued for alleged silver conspiracy

* Hundreds of millions in illegal profit alleged

* Triple damages sought in one of two lawsuits

* CFTC proposed new tools to thwart price manipulation (Adds adviser comment, details)

By Jonathan Stempel

NEW YORK, Oct 27 (Reuters) - JPMorgan Chase & Co (JPM.N) and HSBC Holdings Plc (HSBA.L) were hit with two lawsuits on Wednesday by investors who accused them of conspiring to drive down silver prices, and reaping an estimated hundreds of millions of dollars of illegal profits.

The banks, among the world's largest, were accused of manipulating the market for COMEX silver futures and options contracts from the first half of 2008 by amassing huge short positions in silver futures contracts that are designed to profit when prices fall.

"Defendants reaped hundreds of millions of dollars, if not billions of dollars in profits" from the conspiracy, one of the complaints said.

The respective plaintiffs, Brian Beatty and Peter Laskaris, each said they traded COMEX silver futures and options and contracts, and lost money because of the alleged manipulation.

Beatty lives in Connecticut and Laskaris in New York, court records showed. The lawsuits seek class-action status, damages that may be tripled and other remedies. The defendant banks are major participants in the silver market. (more)