This is in what the plaintiff's law firm called the first nationwide class action over alleged price-fixing of the metals.
In a complaint filed on Tuesday in the US 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 maker of jewellery and police badges, claimed metals purchasers lost millions of dollars.
The defendants illegally shared customer data, used that information to engage in "front-running" of expected price moves, and manufactured phantom "spoof" orders, according to the plaintiff.
Platinum and palladium are used in catalytic converters to curb vehicle emissions, and are also used in dentistry and jewellery.
On 16 October, the London Metal Exchange said it will on 1 December 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. [SBK:Standard Bank] declined to comment.
A spokeswoman for BASF, the world's largest chemicals maker, said the group could not comment because it had not been notified of a complaint.
BASF generated 2.36 billion euros (2.95 billion US dollars) in precious metals trading revenue last year. The London-based trading business is part of BASF's Catalysts division, which is the world's largest maker of catalytic converters.
The law firm Labaton Sucharow represents Modern Settings.