Barry Silbert isn’t done yet. The billionaire entrepreneur first made his mark in finance when, at age 17, he became the youngest person in the U.S. to obtain a stockbroker license. The Maryland native went on to become a Wall Street trader before launching alternative asset platform Second Market, which he sold to NASDAQ. Silbert then hit it big with Bitcoin, buying a hoard when the price was $11 in 2012, and building the crypto conglomerate known as Digital Currency Group. On Wednesday, he ann...