"The difficulties small-time retail traders face in timing these huge runs is that they don’t have access to the same real-time information that large market makers like Citadel Securities do. In addition, the market makers don’t have to play by the same rules.
This is something that traders often don’t understand. There is a market-making exemption for the Citadels and the Two Sigma’s and the Morgan Stanleys and the Goldman Sachs of the world where they don’t have to locate stock to short like you and I would...They have been granted an SEC exemption as market makers from having to locate shares. They can manufacture them." - Jon Quast
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