Fallout from Switzerland's wildly swinging currency ricocheted around the world, hitting global banks with tens of millions of dollars in losses and triggering the collapse of some brokerage firms.

Deutsche Bank suffered about $150 million in losses Thursday after the Swiss National Bank abruptly removed the cap on the Swiss franc's value, sparking a massive franc rally, said a person familiar with the matter. Barclays also racked up tens of millions of dollars in losses, although they totaled less than $100 million, another person said.

Shares in FXCM, the biggest retail foreign-exchange broker in the U.S. and Asia, didn't open Friday for trading on the New York Stock Exchange pending news. FXCM said the unprecedented volatility in the euro against the Swiss franc triggered losses that left it with a negative equity balance.

A U.K. retail broker entered insolvency, and a New Zealand foreign-exchange trading house collapsed. Regulators in Europe and Asia scrambled to assess the damage, seeking information from banks and brokerages and trying to ascertain the potential impact on mom-and-pop investors. People in some cities lined up to change currencies (see picture above, in Geneva).

The losses were triggered by the Swiss franc's 30% jump against the euro in the minutes after the SNB scrapped its cap on the nation's currency relative to the euro. Brokers found themselves unable to trade because of the unexpected volatility and the fact that some big banks stopped quoting rates for francs. Their customers' huge losses, partly exacerbated by high degrees of leverage, quickly eroded the brokerages' financial cushions, tipping some into insolvency.

Wall Street Journal staff

Access Investor Kit for Schweizerische Nationalbank

Visit http://www.companyspotlight.com/partner?cp_code=P479&isin=CH0001319265

Access Investor Kit for Barclays Plc

Visit http://www.companyspotlight.com/partner?cp_code=P479&isin=GB0031348658

Access Investor Kit for Barclays Plc

Visit http://www.companyspotlight.com/partner?cp_code=P479&isin=US06738E2046