I was surfing wiki for fun and went to Gamestop page then Citadel wiki and...
Citadel Regulatory issues
Over a two-year period until September 2014, hundreds of thousands of large OTC orders were removed from its automated trading processes, rendering the orders "inactive" so that they had to be handled manually by human traders. Citadel Securities then "traded for its own account on the same side of the market at prices that would have satisfied the orders," without immediately filling the inactive orders at the same or better prices as required by FINRA rules.[63]
In 2014, Citadel was fined $800,000 for irregularities in its trading practices between March 18, 2010, and Jan. 8, 2013 [64]
In 2017, Citadel was fined $22 million by the SEC for misleading clients regarding the way it priced trades.[65]
In 2018, Citadel was forced by the SEC to pay $3.5 million over violations stemming from incorrect reporting for nearly 80 million trades from 2012 to 2016.[66]
In 2018, Bloomberg reported that 40% of Robinhood's revenues were derived from selling customer orders to firms such as Citadel Securities and Two Sigma Securities.[67]
In January 2020, Citadel paid a 670 million-yuan ($97 million) settlement for alleged trading irregularities dating from 2015.[68]
Citadel Securities was fined $700,000 by FINRA in July 2020 for trading ahead of customer orders.[69] They delayed certain equity orders from clients to buy or sell shares while continuing to trade the same stocks in its own account as part of its market-making activities, according to FINRA.
In 2020, Citadel Securities was censured by FINRA a total of 19 times for a variety of misconduct, including failing to close failure-to-deliver positions, naked short selling, inaccurate reporting of short sale indicators, executing trades during circuit-breaker halts, and failing to offer its clients best prices on the bid-ask spread.[70]
On March 25, 2021, Citadel agreed to a censure by FINRA and a $275,000 fine for improperly reporting nearly 500,000 Treasury transactions between 2017 and 2019, revealing a systemic failure in Citadel's compliance systems.
2008 is coming baby!