Coinbase

Coinbase is the biggest cryptocurrency exchange in the U.S. Founded in 2012, the San Francisco-based company weathered periodic Bitcoin bubbles to become the go-to place for Americans to buy so-called digital gold and other blockchain tokens. Helmed by Brain Armstrong, a former Airbnb engineer, Coinbase is one of the most influential digital finance upstarts challenging Wall Street. Like the PayPal mafia, a diaspora of former Coinbase executives have become influential entrepreneurs in their own right.