Citadel LLC (formerly known as Citadel Investment Group, LLC) is an American multinational hedge fund and financial services company. Founded in 1990 by Kenneth Griffin, the company operates two primary businesses: Citadel, one of the world’s largest alternative asset managers with more than US$35 billion in assets under management (as of October 1, 2020); and Citadel Securities, one of the leading market makers in the world, whose trading products include equities, equity options, and interest rate swaps for retail and institutional clients.