One of the most enduring myths associated with Swiss banks is the money of “unknown” origin that has been hidden in their coffers for generations. Because of a number of laws enacted in the past 15 years, Switzerland’s financial institutions are now tightly regulated, but at least one mystery still remains: who owns hundreds of millions of dollars’ worth of unclaimed assets languishing in the nation’s banks — and how long will they be kept there?

Earlier this month, Switzerland’s parliament set a 62-year deadline for the recovery of unclaimed assets, which are roughly estimated at anywhere from $100 million to $600 million. This means that the banks must keep inactive accounts for six decades after the last contact with the customer, and then turn the assets over to the Swiss government. The new time limit is longer than allowed in most other countries, which liquidate dormant accounts after five to 30 years. And while the deadline is part of larger reforms of the banking sector, it is born out of the scandal that erupted in the 1990s over the dormant World War II accounts stashed in Swiss banks by Jews fleeing Nazi persecution....