A professional day trader can informally be considered somebody who day trades for a living, but from a regulatory perspective, it refers to a trader who is licensed with either their Series 6, 7, 63, 65, or 66. Traders who are licensed pay higher fees for market data. That’s why when you open an account you have to tell them if you are a professional (licensed) trader. Day traders are not required to be licensed if they are trading their own money.
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