In a complaint filed on Tuesday in the U.S. District Court in Manhattan, units of Goldman, BASF, HSBC Holdings Plc and South Africa's Standard Bank Group Ltd were accused of having conspired since 2007 to rig the twice-daily platinum and palladium "fixings" and the prices of futures and options based on those fixings.
The plaintiff, Modern Settings LLC, a Florida-based company that said it bought the metals, claimed purchasers lost millions of dollars because the defendants illegally shared customer data, used that information to engage in "front-running" of expected price moves, and manufactured phantom "spoof" orders.
Platinum and palladium are used in catalytic converters to curb vehicle emissions, and are also used in dentistry and jewellery.
On Oct. 16, the London Metal Exchange said it will on Dec. 1 take charge of platinum and palladium price fixing, and use a new electronic platform.
The Hong Kong Exchanges and Clearing Ltd unit said the platform would replace a benchmark system established in 1989, and run by Goldman, BASF, HSBC and Standard.
The complaint said such changes "have come too late" for Modern Settings and other prospective class members. The complaint seeks unspecified damages for the defendants' alleged violations of U.S. antitrust and commodities laws.
Regulators around the world have tightened scrutiny of pricing benchmarks in recent years after uncovering evidence of rigging in currencies and the London Interbank Offered Rate.
The more stringent regulation has spawned new price setting platforms for gold, silver, platinum and palladium. Metals purchasers have filed similar lawsuits this year accusing banks of gold and silver price-fixing.
Goldman spokesman Michael DuVally and HSBC spokeswoman Juanita Gutierrez declined to comment. BASF and Standard Bank did not immediately respond to requests for comment after market hours in their home countries.
The law firm Labaton Sucharow represents Modern Settings.
The case is Modern Settings LLC v. BASF Metals Ltd et al, U.S. District Court, Southern District of New York, No. 14-09391.
(Reporting by Jonathan Stempel in New York. Editing by Andre Grenon)
By Jonathan Stempel