Brian Armstrong, co-founder and chief executive officer of Coinbase Inc., stands for a photograph at the Coinbase Inc. office in San Francisco, California, U.S., on Friday, Dec. 1, 2017. Coinbase wants to use digital money to reinvent finance. In the company’s version of the future, loans, venture capital, money transfers, accounts receivable and stock trading can all be done with electronic currency, using Coinbase instead of banks. Photographer: Michael Short/Bloomberg