#7 Abigail Johnson ($15.6B): Abigail has served as CEO of Fidelity Investments since 2014, when she took over for her father, and as chairman since 2016. She owns an estimated 24.5% stake of Boston-based mutual fund giant, which has nearly $2.7 trillion in manages assets. Johnson has embraced cryptocurrencies and in 2018, Fidelity launched a platform that allows institutional investors to trade bitcoin and ether.