Wall Street is putting more money behind a technology it once dismissed as a fad.

Some of the biggest companies in the financial sector have invested $30 million in Chain Inc., a San Francisco-based company that works with banks and other institutions to develop ways to trade and transfer financial assets using the system that underpins the virtual currency Bitcoin.

Investors include Visa Inc., Nasdaq Inc., Citi Ventures , Capital One Financial Corp. , Fiserv Inc. and Orange SA .

A valuation for Chain wasn’t disclosed as part of the fundraising round, which Chain announced on Wednesday. The company also said former American Express Co. CEO and venture capitalist Jim Robinson III has joined its board.

The investment is the latest sign of Wall Street’s about-face with Bitcoin, which banks and other financial firms initially said was unlikely to transform commerce. These financial companies don’t have any interest in using the actual currency. But they see the “blockchain” technology that lets Bitcoin users instantaneously make and record transactions as a potential replacement for what they say is a cumbersome, costly and less-secure process.