Hedge Fund Citadel Sees Revenue Top $7 Billion

Citadel Securities, led by Ken Griffin, has significantly increased its market influence and wealth, particularly after the 2008 financial crisis. The firm capitalized on the rise of retail trading through apps like Robin Hood, which route orders to market makers such as Citadel. This strategy, known as payment for order flow, has led to substantial revenue growth, with 2020 revenues reaching $6.7 billion. In January, Griffin sold a stake in Citadel Securities to Sequoia and Paradigm, valuing the firm at nearly $22 billion, while he retains an 80% ownership.

What arrangement is known as payment for order flow?

What percentage of Citadel Securities does Griffin own after the stake sale?